Paving question. Cementing necessary?
Pete Marrow
Her indoors wants somewhere to sit outdoors. I would like to make
a smallish paved area (is that a patio then?) and liked the look of
those small cast-concrete slabs that they used on Ground Force the
other week. Is it obligatory to cement them in, or can one just bed them
down on hardcore with a bed of sand? Are there web resources
on this. Is this a faq and I've offended everyone?
Pete (in Edinburgh)
Nick Maclaren
In article <6uaue6$5...@kwu1.nerc-keyworth.ac.uk>, "Pete Marrow" <P.Ma...@bgs.ac.uk> writes:
|> Oh knowledgeable ones,
While such people are asleep, I shall reply :-)
|> Her indoors wants somewhere to sit outdoors. I would like to make
|> a smallish paved area (is that a patio then?) and liked the look of
|> those small cast-concrete slabs that they used on Ground Force the
|> other week. Is it obligatory to cement them in, or can one just bed them
|> down on hardcore with a bed of sand?
Not at all, and it is positively undesirable to use cement.
Depending on your soil, you may not even need sand! Unless you are
going to be driving vehicles over them, or equivalent, you need to
level and firm the soil well and cover it with a thin (1-2" at most)
layer of sand or equivalent. With my sandy soil, I did it when the
soil was dry and just loosened the top 1" of soil.
|> Are there web resources
|> on this?
Probably. They almost certainly make a meal of the job. It isn't
hard and, if you have not used cement, you can always redo the job
later. I recommend using blocks of not larger than 18" square,
unless you are into heavy lifting. I had a lot of 2'x3' ones left
in the garden, but moving those is a right b*gg*r.
|> Is this a faq and I've offended everyone?
Yes and no, respectively.
Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QG, England.
Email: nm...@cam.ac.uk
Tel.: +44 1223 334761 Fax: +44 1223 334679
John Bravin
>Are there web resources on this.
There is an excellent Web site devoted to paving on
http://www.tmac.clara.net/paving/pavpage/paving.htm
It covers materials, sub-bases, edgings and kerbs, maintenance, drainage,
and tips of the trade. It's created by McCormack & Son, but is a wonderful
example of Web altruism, and if printed out makes a useful 100 page manual
on all aspects of paving.
--
John Bravin
Building in Belgium to Be Close to the Beer
Jane Ransom
<P.Ma...@bgs.ac.uk> writes
>Oh knowledgeable ones,
>
>a smallish paved area (is that a patio then?) and liked the look of
>those small cast-concrete slabs that they used on Ground Force the
>other week. Is it obligatory to cement them in, or can one just bed them
>on this. Is this a faq and I've offended everyone?
>
Have you looked at Cormaic's web pages - you're sure to find something
there.
--
Jane Ransom in Lancaster.
cormaic
(Nick Maclaren) declared:
>
>Not at all, and it is positively undesirable to use cement.
!!!!! I don't think you are going to win many paving
contracts if you are so averse to cement. Good, mortar pointing is
*essential* if you want your flag/slab paving to stay where you put
it. Omitting the mortar allows the flags/slabs to move, and they will!
>
>Depending on your soil, you may not even need sand!
!!!!! Wot? No sand either? It is bad practice to lay *any*
paving on soil - you wouldn't build a wall without a footing!
>Unless you are
>going to be driving vehicles over them, or equivalent, you need to
>level and firm the soil well and cover it with a thin (1-2" at most)
>layer of sand or equivalent. With my sandy soil, I did it when the
>soil was dry and just loosened the top 1" of soil.
That's what is called a 'bodge' job - and it's bad advice.
Soil is not a stable, competent bedding material. Organic material
will decay, clays will settle and the paving will sink.
>
>|> Are there web resources
>|> on this?
>
>Probably. They almost certainly make a meal of the job.
I can't believe I'm reading this. What gives you, a rank
amateur, the right to belittle another mans trade? I spent 5 years
serving my time as a street-mason, probably longer than you spent
studying for a degree. I don't proffer senseless scientific advice,
because it's not my field, but paving *is*, and my company has over 40
years experience in the trade, rather more than your one-off patio
provided you with.
>It isn't
>hard and, if you have not used cement, you can always redo the job
>later.
Yeah! After you've made a bollix of it following bad advice!
Why not do it *right* the first time?
>I recommend using blocks of not larger than 18" square,
>unless you are into heavy lifting. I had a lot of 2'x3' ones left
>in the garden, but moving those is a right b*gg*r.
So leave it to the experts.
For advertisement-free, *professional* advice, from a man that
*can* man-handle 3x2s, and has laid more square metres of paving than
you've had hot dinners, visit my web-site, which covers most common
paving types and methods available in the UK. I'm sure you'll find it
much more useful than this drivel from Nick. The kind folk at the UK
Building Resources certainly thought so when they awarded a 5-star
merit to the site.
--
cormaic - paving pages at http://www.tmac.clara.net/paving2.htm
Culcheth - Last Updated on July 8th 1998
cormaic CAN BE FOUND AT tmac DOT clara DOT net
Nick Maclaren
cormaic <cor...@NOSPAMTODAYTHANKStmac.clara.net> wrote:
>'Twas 23 Sep 1998 14:10:51 GMT, when the most noble nm...@cus.cam.ac.uk
>(Nick Maclaren) declared:
>
>>Not at all, and it is positively undesirable to use cement.
>
> !!!!! I don't think you are going to win many paving
>contracts if you are so averse to cement. Good, mortar pointing is
>*essential* if you want your flag/slab paving to stay where you put
>it. Omitting the mortar allows the flags/slabs to move, and they will!
You are clearly a modernist. You may be unaware that the traditional
way of laying paving bricks, slabs, crazy paving etc. is without any
form of mortar. If competently done, they don't shift.
>>Depending on your soil, you may not even need sand!
>
> !!!!! Wot? No sand either? It is bad practice to lay *any*
>paving on soil - you wouldn't build a wall without a footing!
The mind boggles. The loading imposed by a mere 3' wall is 18 times
that imposed by a 2" slab - actually, it is much more, because of the
fluid stability effect, but let that pass. And that imposed by a
typical house wall may be 200 times greater.
What you do think that happens to sand, incidentally? And, remember
that I did say that my soil was sandy.
>>Unless you are
>>going to be driving vehicles over them, or equivalent, you need to
>>level and firm the soil well and cover it with a thin (1-2" at most)
>>layer of sand or equivalent. With my sandy soil, I did it when the
>>soil was dry and just loosened the top 1" of soil.
>
> That's what is called a 'bodge' job - and it's bad advice.
>Soil is not a stable, competent bedding material. Organic material
>will decay, clays will settle and the paving will sink.
The word you are looking for is "botch" - to "bodge" something implies
to make it to the highest possible standard :-)
You are correct that the slabs will shift if the soil is not properly
firmed. You are not correct that anything else needs to be done.
The slabs in my garden have not shifted 1/8" in 20 years.
>>|> Are there web resources
>>|> on this?
>>
>>Probably. They almost certainly make a meal of the job.
>
> I can't believe I'm reading this. What gives you, a rank
>amateur, the right to belittle another mans trade? I spent 5 years
>serving my time as a street-mason, probably longer than you spent
>studying for a degree. I don't proffer senseless scientific advice,
>because it's not my field, but paving *is*, and my company has over 40
>years experience in the trade, rather more than your one-off patio
>provided you with.
I think that you are being foolish. If you really insist, I will
repeat the advice that I got when I got my drive laid with concrete
bricks. And that wasn't just from the firms quoting for the contract,
but from disinterested parties, too.
>>It isn't
>>hard and, if you have not used cement, you can always redo the job
>>later.
>
> Yeah! After you've made a bollix of it following bad advice!
You are evidently unaware that paths and patios laid 200 years back
(a) were not laid using cement and (b) are often in good condition
today. You are also evidentally unaware that people often change
their minds and want to turn patios back into places that they can
grow things.
Judith Lea
<nm...@cus.cam.ac.uk> writes
>> Yeah! After you've made a bollix of it following bad advice!
>
>You are evidently unaware that paths and patios laid 200 years back
>(a) were not laid using cement and (b) are often in good condition
>today. You are also evidentally unaware that people often change
>their minds and want to turn patios back into places that they can
>grow things.
Oh dear, I am so sad to see this, Nick MacLaren who is very knowledgable
on plants etc., and Cormaic who is an expert Mason. After carefully
reading every word, I would go along with Cormaic's advice for the
following reasons:
1) He is an expert with many years experience;
2) He builds with permanency in mind;
3) I had a small patio laid following advice similar to Nick's and
lived to regret it dearly, in more ways than one.
Nick gave good advice from, his perspective, which I respect but his
comment regarding people changing their mind later on is not a valid
reason to build in a temporary style. When I asked my builder to build
me a patio, I meant a permanent one; not one which would sink and move.
I appreciate Nick's valuable advice regarding a number of things and
equally I value Cormaic's advice on building matters. To put it in a
nutshell, for plant advice I would probably follow Nick and for building
advice, I would certainly follow Cormaic.
Don't fall out you guy's, you both seem extremely nice.
--
Judith Lea
Alan J Holmes
With all due respects, I can't help feeling you've gone a little
over the top with this:-
>'Twas 23 Sep 1998 14:10:51 GMT, when the most noble nm...@cus.cam.ac.uk
>(Nick Maclaren) declared:
>>Not at all, and it is positively undesirable to use cement.
> !!!!! I don't think you are going to win many paving
>contracts if you are so averse to cement. Good, mortar pointing is
>*essential* if you want your flag/slab paving to stay where you put
>it. Omitting the mortar allows the flags/slabs to move, and they will!
I didn't get the impression that Nick was aiming to get paving
contracts, he was offering advice from one amateur to another, as
for the mortar stopping the flags moving, does it _really_ matter
to am amateur?
>>Depending on your soil, you may not even need sand!
> !!!!! Wot? No sand either? It is bad practice to lay *any*
>paving on soil - you wouldn't build a wall without a footing!
I always lay my paving directly upon the soil, sure they move,
but again, does it matter?
I'm not aiming for a proffesionable finish and I have a usable
patio.
>>Unless you are
>>going to be driving vehicles over them, or equivalent, you need to
>>level and firm the soil well and cover it with a thin (1-2" at most)
>>layer of sand or equivalent. With my sandy soil, I did it when the
>>soil was dry and just loosened the top 1" of soil.
> That's what is called a 'bodge' job - and it's bad advice.
>Soil is not a stable, competent bedding material. Organic material
>will decay, clays will settle and the paving will sink.
True, but again, for the amateur, does it matter?
>>|> Are there web resources
>>|> on this?
>>Probably. They almost certainly make a meal of the job.
> I can't believe I'm reading this. What gives you, a rank
>amateur, the right to belittle another mans trade? I spent 5 years
>serving my time as a street-mason, probably longer than you spent
>studying for a degree. I don't proffer senseless scientific advice,
>because it's not my field, but paving *is*, and my company has over 40
>years experience in the trade, rather more than your one-off patio
>provided you with.
I didn't see the article as belittling your trade, we cannot all
be experts in the fieild of paving but out febble attempts are
satisfactpry to us, if the original author had wanted to pay
someone for a proffessional job he would have looked in Yellow
Pages, but he obvious didn't, for what reason he didn't say.
>>It isn't
>>hard and, if you have not used cement, you can always redo the job
>>later.
> Yeah! After you've made a bollix of it following bad advice!
But again, he's using his own time and resouces so, does it
matter?
And it's very satisfying to produce something under your own
steam, even if it is not perfect.
> Why not do it *right* the first time?
The effort, cost, and as an amateur not getting it right the
first time!
>>I recommend using blocks of not larger than 18" square,
>>unless you are into heavy lifting. I had a lot of 2'x3' ones left
>>in the garden, but moving those is a right b*gg*r.
> So leave it to the experts.
But perhaps he can't afford the 'experts' exhorbitant fees!
> For advertisement-free, *professional* advice, from a man that
>*can* man-handle 3x2s, and has laid more square metres of paving than
>you've had hot dinners, visit my web-site, which covers most common
>paving types and methods available in the UK. I'm sure you'll find it
>much more useful than this drivel from Nick. The kind folk at the UK
>Building Resources certainly thought so when they awarded a 5-star
>merit to the site.
I'm glad for you and I'm sure your web page does offer much good
advice, but will it give the man the instant experience to do the
job 'right' the first time?
I've also laid many 3 X 2s but the effort now of manhandling them is
getting beyond a joke, so I now have degenerated to 2 X 2s!
My paving is not perfect but it suits me.
--
Alan G4CRW, Ex FAA, RNARS and others!
Here I sit, giving the world the benefit of my words of wit and wisdom!
What an exciting life I lead!(:-)
Jane Ransom
<Jud...@nanime.demon.co.uk> writes
> To put it in a
>nutshell, for plant advice I would probably follow Nick and for building
>advice, I would certainly follow Cormaic.
>
>Don't fall out you guy's, you both seem extremely nice.
Judith, as ever, pouring oil on troubled waters :)))
Where would we be without you, Judith :)))))))))))
ia...@teleord.co.uk
xxx...@brunel.ac.uk (Alan J Holmes) that wrote:
<snip>
> I'm not aiming for a proffesionable finish and I have a usable
> patio.
<snip>
> But again, he's using his own time and resouces so, does it
> matter?
It might do to the original poster. I certainly wouldn't like to spend
a couple of weekends doing something, it not being up to the
standard I wanted, and having to repeat it in a years time, I'd like
to do a good (enough) job first time, so I can spend more time on the
plants/relaxing with a beer.
> And it's very satisfying to produce something under your own
> steam, even if it is not perfect.
<snip>
True. I have just completed a raised brick bed on the end of my
patio. I'm sure if a brickie saw it they may be less than impressed,
but I think it's ok, I've rested a beer and my backside on it, and it
hasn't fallen over.
> I'm glad for you and I'm sure your web page does offer much good
> advice, but will it give the man the instant experience to do the
> job 'right' the first time?
It is a v. good page, I've yet to lay any paving, but when/if I do, I'll
be looking at cormiacs pages first.
> My paving is not perfect but it suits me.
Trouble is, we don't know what quality of job the original poster
wants. At least now they have a choice of whose advice to take,
depending on what quality finish they may or may not want.
Admittedly cormiac did seem to fly off the handle a bit, but then
seeing as someone had just rubbished his raison d'etre, I'm
not entirely suprised. Bit like when people dismiss working
in the computer industry as "staring at a screen all day, ooh no,
couldn't do that!", that annoys me!
Adios Amigos!
Ian.
--
This post does not reflect the opinions of Whitakers.
Nick Maclaren
In article <6udq00$bfh$1...@armadillo.live.teleordering.co.uk>, ia...@teleord.co.uk writes:
|> It could have been aliens, the CIA, or maybe even
|> xxx...@brunel.ac.uk (Alan J Holmes) that wrote:
|>
|> <snip>
|> > I'm not aiming for a proffesionable finish and I have a usable
|> > patio.
|> <snip>
|> > But again, he's using his own time and resouces so, does it
|> > matter?
|>
|> It might do to the original poster. I certainly wouldn't like to spend
|> a couple of weekends doing something, it not being up to the
|> standard I wanted, and having to repeat it in a years time, I'd like
|> to do a good (enough) job first time, so I can spend more time on the
|> plants/relaxing with a beer.
It generally does to me, too. I usually reckon to do a BETTER job
than most professionals, and spend a horrific amount of time in fixing
up the messes they have made. And just because you pay more doesn't
necessarily mean you get a better job done :-(
|> Trouble is, we don't know what quality of job the original poster
|> wants. At least now they have a choice of whose advice to take,
|> depending on what quality finish they may or may not want.
Do you? I don't think that you do. My sources and experience
(INCLUDING that Web page) are that cement is bad news if you want
something to last many decades, or centuries, unless you build it
to industrial (rather than domestic) standards. And then, God help
you if you need access to services underneath it!
The key to longevity is recognising the conditions, and using
careful AND APPROPRIATE preparation. For example, clay is a problem,
but sand and gravel aren't. Less obviously, you need MUCH deeper
foundations if you are going to use cement (especially on clay)
than if you aren't.
|> Admittedly cormiac did seem to fly off the handle a bit, but then
|> seeing as someone had just rubbished his raison d'etre, I'm
|> not entirely suprised. Bit like when people dismiss working
|> in the computer industry as "staring at a screen all day, ooh no,
|> couldn't do that!", that annoys me!
That is codswallop. He didn't read my posting, or even that Web
page, before getting abusive. If you look at it, you will see that
it confirms a great deal of what I said.
Kay
>
> That's what is called a 'bodge' job - and it's bad advice.
>Soil is not a stable, competent bedding material. Organic material
>will decay, clays will settle and the paving will sink.
>
So to help me understand ... presumably the soil settles anyway. So why
doesn't the sand just follow the same outline? I guess because the sand
can shift and fill in any hollows that develop? Concrete can't shift. So
why doesn't it just crack?
It must work because you put concrete under walls, and they don't crack,
I just don't see how!
--
Kay
k...@scarboro.demon.co.uk
Aonghas P MacKenzie
from Kay <k...@scarboro.demon.co.uk> contains these words:
> OK. I can see the sense in this.
> So to help me understand ... presumably the soil settles anyway. So why
> doesn't the sand just follow the same outline? I guess because the sand
> can shift and fill in any hollows that develop? Concrete can't shift. So
> why doesn't it just crack?
> It must work because you put concrete under walls, and they don't crack,
> I just don't see how!
> --
> Kay
Soil contains organic matter. Organic matter deacys into
carbon-dioxide and water mainly, with a little ammonia and suchlike
mixed in. A minute mineral residue remains, so soil will shrink by
its organic content over time.
Sand contains no organic matter so will only settle insofar as the
grains rearrange themselves to eliminate spaces between them.
Concrete does crack if laid on sol, which is why foundations are dug
well into the (relatively) organics-free subsoil.
On subsoils which move when the water content varies (clays
especially) buildings are often put on a raft of reinforced concrete.
--
Aonghas Mackenzie
Nick Maclaren
Kay <k...@scarboro.demon.co.uk> wrote:
>cormaic wrote
>>
>> That's what is called a 'bodge' job - and it's bad advice.
>>Soil is not a stable, competent bedding material. Organic material
>>will decay, clays will settle and the paving will sink.
>>
>So to help me understand ... presumably the soil settles anyway. So why
>doesn't the sand just follow the same outline? I guess because the sand
>can shift and fill in any hollows that develop? Concrete can't shift. So
>why doesn't it just crack?
>
>It must work because you put concrete under walls, and they don't crack,
>I just don't see how!
You are 100% correct on all counts, except believing that walls don't
crack!
The purpose of a house footing is to make a concrete raft that 'floats'
on top of stable soil - in the case of clay in the UK, this means soil
that never dries out enough to shrink significantly. When building
regulations were first introduced, they specified a minimum depth and
size of concrete believed to be 'safe'. The depth is critical to get
down to the permanently damp soil.
We then had several very dry years in succession, and many of those
houses suffered subsidence damage (including cracking of their footings
and walls.) The insurance companies jacked their premiums and added
exclusions, and the building regulations were changed. They are now
quite mind-boggling.
Houses on (coarse) sand and gravel, which do NOT shrink when they dry
out, were almost all unaffected by the drought, even when they had
what would now be regarded as inadequate foundations. I live in one.
But they are now built with foundations that are far deeper and more
expensive than necessary.
More interestingly, the traditional building construction of timber
on dry-laid brick didn't suffer either, and that was because the brick
could move with the soil, and the timber is flexible enough not to be
affected by a slight change in geometry. When I say "traditional",
please understand that I am understating the case :-)
cormaic
(Nick Maclaren) declared:
>
>You are clearly a modernist. You may be unaware that the traditional
>way of laying paving bricks, slabs, crazy paving etc. is without any
>form of mortar. If competently done, they don't shift.
The traditional forms of paving, as you call the, have always
relied on edges being fixed, often by sinking a keel stone or a series
of them. And the use of lime-mortars, the forerunner of modern
cements, is typical of many 'traditional' pavements.
Despite your convictions, modernism does not equate with
over-engineering. If your 'traditional' methods are so good, why are
they not accepted practice throughout the construction industry, from
Architects down to the lads on the tools?
The Romans built good roads, some have survived 2000 years,
and they didn't have modern cement, but we have refined their
techniques, and I believe that modern paving is much more user
friendly.
>
>>>Depending on your soil, you may not even need sand!
>>
>> !!!!! Wot? No sand either? It is bad practice to lay *any*
>>paving on soil - you wouldn't build a wall without a footing!
>
>The mind boggles. The loading imposed by a mere 3' wall is 18 times
>that imposed by a 2" slab - actually, it is much more, because of the
>fluid stability effect, but let that pass. And that imposed by a
>typical house wall may be 200 times greater.
I wasn't claiming the load factors were the same, I was trying
to make an analogy. Perhaps a better one would be that you wouldn't
lay a decent carpet without underlay.
>
>What you do think that happens to sand, incidentally? And, remember
>that I did say that my soil was sandy.
For home-use, your sandy soil might be fine, but would not be
acceptable to my standards, nor on any proper paving contract. The
Resident Engineer would chuck me off the site if I turned up with a
load of sandy soil to lay the paving upon!
8<---S-N-I-P--->8
>
>The word you are looking for is "botch" - to "bodge" something implies
>to make it to the highest possible standard :-)
Regional variation maybe, but to 'bodge' a job is to make
shoddy work, to cut corners, to paper over cracks, or at least it is
my my part of the world.
>
>You are correct that the slabs will shift if the soil is not properly
>firmed. You are not correct that anything else needs to be done.
>The slabs in my garden have not shifted 1/8" in 20 years.
Lucky you! - but you can't extrapolate a universal rule
because the flags in your garden haven't moved. i think your paving is
the exceptiuuon, and not the rule.
>
>>>|> Are there web resources
>>>|> on this?
>>>
>>>Probably. They almost certainly make a meal of the job.
>>
>> I can't believe I'm reading this. What gives you, a rank
>>amateur, the right to belittle another mans trade? I spent 5 years
>>serving my time as a street-mason, probably longer than you spent
>>studying for a degree. I don't proffer senseless scientific advice,
>>because it's not my field, but paving *is*, and my company has over 40
>>years experience in the trade, rather more than your one-off patio
>>provided you with.
>
>I think that you are being foolish. If you really insist, I will
>repeat the advice that I got when I got my drive laid with concrete
>bricks. And that wasn't just from the firms quoting for the contract,
>but from disinterested parties, too.
I refer you to BS 6717 and BS 7533 which lay out a design
procedure for the construction of flexible pavements from concrete
block pavers. Basically, a sub-base, a bedding layer, and the
surface layer. Blocks laid on bare earth, no matter how sandy, is not
the accepted standard of construction.
>
>>>It isn't
>>>hard and, if you have not used cement, you can always redo the job
>>>later.
>>
>> Yeah! After you've made a bollix of it following bad advice!
>
>You are evidently unaware that paths and patios laid 200 years back
>(a) were not laid using cement
Not cement, but its predecessor, a lime-based mortar, or
pitch, or powdered ash, or even clean sand. Joints were *not* left
open as you seem to believe.
>and (b) are often in good condition
>today.
For the reasons outlined above.
>You are also evidentally unaware that people often change
>their minds and want to turn patios back into places that they can
>grow things.
>
As a professional tradesman, I build to last.
cormaic
<k...@scarboro.demon.co.uk> declared:
>cormaic wrote
>>
>> That's what is called a 'bodge' job - and it's bad advice.
>>Soil is not a stable, competent bedding material. Organic material
>>will decay, clays will settle and the paving will sink.
>>
>OK. I can see the sense in this.
>So to help me understand ... presumably the soil settles anyway. So why
>doesn't the sand just follow the same outline? I guess because the sand
>can shift and fill in any hollows that develop?
The idea is that there should be no topsoil beneath the
paving. The sand bedding layer should be placed on a sub-base of
acceptable material. For 'garden' purposes, this should be the
sub-soil, or undistrurbed, uncultivated soil, if you are blessed with
a decent depth of it.
The sand is not intended to move about beneath the paving,
although this does happen in some cases. The sub-soil is assumed to be
relatively stable and compact to take the load of a patio.
>Concrete can't shift. So
>why doesn't it just crack?
It does, unfortunately, just have a look at some of the
driveways in your local area, there's bound to be a few exhibiting
cracked mass concrete.
>
>It must work because you put concrete under walls, and they don't crack,
>I just don't see how!
It's the principal of spreading the load. A 225mm wide wall
may be built on a 450mm or 600mm wide concrete foundation. The surplus
width is refered to as 'spread'.
cormaic
xxx...@brunel.ac.uk (Alan J Holmes) declared:
>
>I didn't get the impression that Nick was aiming to get paving
>contracts, he was offering advice from one amateur to another, as
>for the mortar stopping the flags moving, does it _really_ matter
>to am amateur?
Maybe not. But I can only offer professional advice
>
>I always lay my paving directly upon the soil, sure they move,
>but again, does it matter?
8<---S-N-I-P--->8
>
>True, but again, for the amateur, does it matter?
>
8<---S-N-I-P--->8
>
>But again, he's using his own time and resouces so, does it
>matter?
>
8<---S-N-I-P--->8
>
>But perhaps he can't afford the 'experts' exhorbitant fees!
Exhorbitant! I suggest you investigate the 'going-rate' for
laying paving. I've seen the same rate for the last 5 years, and a
driop of almost 50% since 1989.
>
>I'm glad for you and I'm sure your web page does offer much good
>advice, but will it give the man the instant experience to do the
>job 'right' the first time?
It is intended to show how to do it correctly. It won't mnake
an expert of you, but it will point you in the right direction.
For those who require personal tuition, I'm afraid we're not
'taking-on' just at the moment. ;~)
>
>I've also laid many 3 X 2s but the effort now of manhandling them is
>getting beyond a joke, so I now have degenerated to 2 X 2s!
I can't even manage them anymore :~(
>
>My paving is not perfect but it suits me.
Fine, as long as you're happy, jobsaguddun :~)
cormaic
(Nick Maclaren) declared:
>It generally does to me, too. I usually reckon to do a BETTER job
>than most professionals, and spend a horrific amount of time in fixing
>up the messes they have made. And just because you pay more doesn't
>necessarily mean you get a better job done :-(
Maybe true, but I accept your challenge to lay a better patio,
driveway, roadway, freight yard, shopping precinct or whatever, better
than I can. And I'm a bloody cripple!
I think you're over-estimating your talents, insulting a
skilled craft, and tarring every builder with the same brush. Indeed,
there are rogues in the building trade, and it seems that you
specialise in employing them, if you're repeatedly 'fixing up the
messes they have made'. I trust you don't display these delusions to
your mechanic, or a waiter.
ia...@teleord.co.uk wrote...
>
>|> Trouble is, we don't know what quality of job the original poster
>|> wants. At least now they have a choice of whose advice to take,
>|> depending on what quality finish they may or may not want.
>
>Do you? I don't think that you do. My sources and experience
>(INCLUDING that Web page) are that cement is bad news if you want
>something to last many decades, or centuries, unless you build it
>to industrial (rather than domestic) standards. And then, God help
>you if you need access to services underneath it!
Do you know something that the construction industry doesn't?
If cement is so awful, why are we still using it? And does 'that
webpage' refer to my site? If so, please tell me exactly where I state
that cement is bad news. As for services, what are we to do? How do
you get a driveway up to your front door, without crossing countless
mains and services?
>
>The key to longevity is recognising the conditions, and using
>careful AND APPROPRIATE preparation. For example, clay is a problem,
>but sand and gravel aren't. Less obviously, you need MUCH deeper
>foundations if you are going to use cement (especially on clay)
>than if you aren't.
>
>|> Admittedly cormiac did seem to fly off the handle a bit, but then
>|> seeing as someone had just rubbished his raison d'etre, I'm
>|> not entirely suprised. Bit like when people dismiss working
>|> in the computer industry as "staring at a screen all day, ooh no,
>|> couldn't do that!", that annoys me!
That was/is my feeling exactly. I have a week-end odd-jobber
telling one and all that he can lay paving better than a contractor
with 20 years on-the-tools experience, and that we, the construction
industry, are in some way misleading, or ripping-off the public.
I'm damned proud of my skills, and I have tried to advise
people the best I can, with no commercial gain for myself. I will not
tolerate my skills being ridiculed by some gobshite.
>
>That is codswallop. He didn't read my posting, or even that Web
>page, before getting abusive. If you look at it, you will see that
>it confirms a great deal of what I said.
I've read your post, Nick, and I've lost all the respect I
once had for you. I don't pontificate on matters outside my realm;
maybe you should follow my example.
This thread has become incendiary, and I'd prefer any
follow-ups to be by email, as it is becoming off-topic and possibly
over-technical for a gardening ng.
Dave Tomlinson
Anyone who reads URG and answers questions about paving
knows that they have got to be right or called cormaic!
(which amounts to the same thing!)
When I used your advice on a couple of local lads the
cowboy was rapidly sorted from the good guy.
DaveT
cormaic <cor...@NOSPAMTODAYTHANKStmac.clara.net> wrote in
article <360c6793....@news.clara.net>...
> 'Twas 23 Sep 1998 14:10:51 GMT, when the most noble
nm...@cus.cam.ac.uk
> (Nick Maclaren) declared:
>
Kay
>The message <JOXWJvA6...@scarboro.demon.co.uk>
> from Kay <k...@scarboro.demon.co.uk> contains these words:
>
>> So to help me understand ... presumably the soil settles anyway. So why
>> doesn't the sand just follow the same outline? I guess because the sand
>> why doesn't it just crack?
>
>> I just don't see how!
>
>> Kay
>
> Soil contains organic matter. Organic matter deacys into
>carbon-dioxide and water mainly, with a little ammonia and suchlike
>mixed in. A minute mineral residue remains, so soil will shrink by
>its organic content over time.
> Sand contains no organic matter so will only settle insofar as the
>grains rearrange themselves to eliminate spaces between them.
Yes I understand that.
But the sand is *on* *top* of the soil, and sand is not self supporting,
so if the soil is shrinking and settling, then the sand will trickle
down to fill the hollows.
> Concrete does crack if laid on sol, which is why foundations are dug
>well into the (relatively) organics-free subsoil.
OK. So why will laying a patio on concrete make it more stable, because
presumably you are not going to put the concrete deep enough to get into
the subsoil?
> On subsoils which move when the water content varies (clays
>especially) buildings are often put on a raft of reinforced concrete.
>
I hate to think what (if anything) is holding up our Victorian house -
two-foot stone walls on wet Yorkshire clay.
--
Kay
k...@scarboro.demon.co.uk
Kay
>>I just don't see how!
>
>crack!
>
>The purpose of a house footing is to make a concrete raft that 'floats'
>on top of stable soil - in the case of clay in the UK, this means soil
>that never dries out enough to shrink significantly. When building
>regulations were first introduced, they specified a minimum depth and
>size of concrete believed to be 'safe'.
But a concrete base to a patio won't get down that far? But will it stay
permanently wet becuase of the patio above it?
> The depth is critical to get
>down to the permanently damp soil.
I begin to wish I'd never started this discussion, having been under the
house to see the join between the 'old' (1870) bit and the 'new' (1880)
bit ... and the dryness of the soil there..
No wonder our surveyor said 'It seems as if the entire extension is
subsiding away from the main body of the house...'
--
Kay
k...@scarboro.demon.co.uk
paulw...@my-dejanews.com
"Pete Marrow" <P.Ma...@bgs.ac.uk> wrote:
> Oh knowledgeable ones,
(and short fused apparently).
To try and summarise the flame-war, including mainly the technical,
and omitting the escalating vitriol:
The question was "is concrete neccessary".
Nick's answer is "No. I've done it and it's lasted OK (so far)"
Cormaic's answer is "Yes, if you want a top quality, permanent job"
I don't think the 2 answer are *that* contradictory. It's more a
dispute about ends than means.
Please calm down, URG needs you both. You seem to have touched a sore
spot in each other.
BugBear.
-----== Posted via Deja News, The Leader in Internet Discussion ==-----
http://www.dejanews.com/rg_mkgrp.xp Create Your Own Free Member Forum
Alan J Holmes
cormaic <cor...@NOSPAMTODAYTHANKStmac.clara.net> wrote:
>'Twas 23 Sep 1998 22:36:27 GMT, when the most noble nm...@cus.cam.ac.uk
>(Nick Maclaren) declared:
>8<---S-N-I-P--->8
>>The word you are looking for is "botch" - to "bodge" something implies
>>to make it to the highest possible standard :-)
> Regional variation maybe, but to 'bodge' a job is to make
>shoddy work, to cut corners, to paper over cracks, or at least it is
>my my part of the world.
That is what the word has developed into in common
parlance, but 'bodgers' were highly skilled men who made
a living turning chair legs and backs in the woods, using
very primitive lathes from whippy branches and cord.
So there!
Anne Taylor
cormaic wrote in message <3610c793....@news.clara.net>...
>8<---S-N-I-P--->8
>>
>>The word you are looking for is "botch" - to "bodge" something implies
>>to make it to the highest possible standard :-)
>
> Regional variation maybe, but to 'bodge' a job is to make
>shoddy work, to cut corners, to paper over cracks, or at least it is
>my my part of the world.
<snip>
I'm getting a delightful picture here of Nick asking all his contractors to
"bodge" the jobs they do for him, meaning in his terms to do it well,
whereas most of the rest of the UK probably understand "bodge" and "botch"
to mean the same thing. (So does my dictionary incidently.) Perhaps that
is why Nick has to "spend a horrific amount of time in fixing
up the messes they have made"!!
Made me smile anyway, however you're supposed to lay a patio.
Anne
Kay
>'Twas Thu, 24 Sep 1998 08:30:02 +0100, when the most noble Kay
><k...@scarboro.demon.co.uk> declared:
>
>
>>Concrete can't shift. So
>>why doesn't it just crack?
>
>driveways in your local area, there's bound to be a few exhibiting
>cracked mass concrete.
But weren't you advocating using concrete as a base? If it cracks, why
does it make a good base?
I'm not trying to argue, just trying to understand. And probably being
incredibly dense.
--
Kay
k...@scarboro.demon.co.uk
Pau...@my-dejanews.com
necessary for a paved area. As a Garden Designer I have to side with Cormaic.
The most certainly are! A fair number of my design jobs have involved
rebuilding what I term a "jobbing builders patio" laid by the cheapskate
builder who built the extension\conseraatory\house using minimal foundations
very much like the method advocated by Nick instead of the
excavation\sub-base\base\paving method advocated by Cormaic. Re-building has
been necessary bacause of the ski slopes rapidly forming as the garden soil
beneath the paving setles. Yes it is possible to get away with minimal
foundations but ONLY on undisturbed soil with minimal oranic matter content.
I have a real time experiment running on this at the moment. A few months ago
I designed and contract managed a new driveway for a house around the corner.
A few doors away another house had a drive laid at the same time, for that
job 4 guys turned up, stripped off some of the existing concrete drive
surface, Whacked the rest into the soil using a plate vibrator, threw down
2in of sharp sand put the blocks on top, and haunched edging blocks with no
other footing than the said sand. Joint were filled with builders sand. Job
took 1 week!
For my job, two guys dug out to 200mm, set edging blocks on concrete strip
footing,laid 100mm hardcore (Mot type I, for the technically minded), laid
50mm sharp sand and compacted with plate vibrator before laying blocks and
filling joints with kiln dried sand. Duration of job: 4 days.
Now, less than 6 months later one of these driveways has weed growing in ever
widening joints between the bricks and shows clear depressions where the car
runs and the edging had moved. The other is perfectly level and weed free. No
prizes for guessing which is which!
Depends what you want I suppose, but I guess most people want something that
will last and look good for a long time. For that Cormaic's advice on footings
and cement is to be commended.
PaulK
Nick Maclaren
>
>The most certainly are! A fair number of my design jobs have involved
>rebuilding what I term a "jobbing builders patio" laid by the cheapskate
>builder who built the extension\conseraatory\house using minimal foundations
>very much like the method advocated by Nick instead of the
>excavation\sub-base\base\paving method advocated by Cormaic. Re-building has
>been necessary bacause of the ski slopes rapidly forming as the garden soil
>beneath the paving setles. Yes it is possible to get away with minimal
>foundations but ONLY on undisturbed soil with minimal oranic matter content.
I really am getting a little tired of being quoted out of context,
and even misquoted. I made a comment SPECIFICALLY about an amateur
building a patio, and there are damn good reasons for what I said.
One of the points that both Cormaic and you have missed is that there
are often important services running underneath the ground, and they
are often too shallow and rarely documented for older houses.
Digging out 8-12" is precisely the right depth to risk damaging such
services without exposing them - I know several people who have had
their new drives dug up for this reason.
Amateurs should generally NOT attempt to fiddle with foundations and
main service pipes because the chances of a serious accident are quite
high. Actually, the same seems to be true for driveway constructors,
though you may justifiably claim that the more reputable companies do
better.
>I have a real time experiment running on this at the moment. A few months ago
>I designed and contract managed a new driveway for a house around the corner.
>A few doors away another house had a drive laid at the same time, for that
>job 4 guys turned up, stripped off some of the existing concrete drive
>surface, Whacked the rest into the soil using a plate vibrator, threw down
>2in of sharp sand put the blocks on top, and haunched edging blocks with no
>other footing than the said sand. Joint were filled with builders sand. Job
>took 1 week!
>
>For my job, two guys dug out to 200mm, set edging blocks on concrete strip
>footing,laid 100mm hardcore (Mot type I, for the technically minded), laid
>50mm sharp sand and compacted with plate vibrator before laying blocks and
>filling joints with kiln dried sand. Duration of job: 4 days.
>
>Now, less than 6 months later one of these driveways has weed growing in ever
>widening joints between the bricks and shows clear depressions where the car
>runs and the edging had moved. The other is perfectly level and weed free. No
>prizes for guessing which is which!
So what? You know damn well that the requirements of a driveway are
totally different from that of a patio. If you look at that Web page
that everybody refers to, it says precisely that. You are talking
about much higher loadings for the former.
Furthermore, the materials are of far less importance than the care
taken in the construction. I have a driveway made according to the
regulations (and your description) by a reputable company, and it HAS
depressed in places. I know lots of other people with the same
experience. The reason is usually that they took insufficient care
with the plate vibrator. The areas that I have relaid have not, of
course, moved at all - and I don't own a plate vibrator.
cormaic
(Nick Maclaren) declared:
>
>I really am getting a little tired of being quoted out of context,
>and even misquoted. I made a comment SPECIFICALLY about an amateur
>building a patio, and there are damn good reasons for what I said.
>One of the points that both Cormaic and you have missed is that there
>are often important services running underneath the ground, and they
>are often too shallow and rarely documented for older houses.
You will grant that I have dug off more patios/driveways etc
than your goodself, and I can tell you that services are not 'often
too shallow', as you suspect.
All utility contractors are obliged to maintain their
equipment at a safe working depth. For water, this is taken as 900mm
below ground level, for frost protection. Gas, electricity, telephone,
and cable are not as strict. However, ALL utility contractors will
come out to any pipe or cable exposed in the construction of a
domestic driveway or patio and use their own labour to sink or renew
the service, at a lower, safer depth.
I undertake approximately 200 domestic paving jobs each year.
For the last year for which records are available, we had to call out
the Electricity supplier once and BT on two occasions, on a turnover
of 212 jobs. Thats 3/212 or 1 in 70 - not 'often'.
>
>Digging out 8-12" is precisely the right depth to risk damaging such
>services without exposing them - I know several people who have had
>their new drives dug up for this reason.
Then that is shoddy work by the contractor, and your
colleagues ought to claim against the contractors insurance. It is
usually pretty easy for an experienced contractor to identify exactly
where services run, and take the appropriate action. If unsure, the
utility co's offer a 'dial-before-you-dig' service.
>
>Amateurs should generally NOT attempt to fiddle with foundations and
>main service pipes because the chances of a serious accident are quite
>high.
True. If you expose foundations when excavating for domestic
paving, then you are either too deep with your dig, or the foundations
are too shallow. If you encounter drainage pipes, these should be
concrete haunched for protection. If you encounter any services, you
should call the relevant utility co. Basic common sense.
>Actually, the same seems to be true for driveway constructors,
>though you may justifiably claim that the more reputable companies do
>better.
I should hope so. It is not in the interest of a reputable
contractor to take a risk with any services. The utility co's do it
for free, and accept the liability, so why risk your employees, or
your client?
So what would you suggest we do? Never replece or extend any
paving, just in case we should chance upon a shallow telephone wire?
How do I pacify a client when I leave his driveway 3m short of the
front door, because the gas pipe feeds in somewhere near there?
This is the real world. Some of us resolve these problems as
our way of making a living. Many of us are professionals, we know what
we are doing; if we didn't the country would be littered with frazzled
or gassed or drowned citizens, in your scenario!
>
8<---S-N-I-P--->8 Nicks comments on Pauls contribution.
>
>Furthermore, the materials are of far less importance than the care
>taken in the construction.
I would argue that *both* are critical. There are a lot of
shoddy paving materials on sale, and a fair few 'cheaper' aggregates,
but why gamble?
>I have a driveway made according to the
>regulations (and your description) by a reputable company, and it HAS
>depressed in places. I know lots of other people with the same
>experience. The reason is usually that they took insufficient care
>with the plate vibrator.
Do you have an engineers report to that effect, or is that
just your guess? It could be settlement over a drainage trench, badly
backfilled years before your driveway was laid.
>The areas that I have relaid have not, of
>course, moved at all - and I don't own a plate vibrator.
I think you're a bit hasty to take the credit for that, as all
you have done is remedial work to the existing contractors work, not
reconstructed the entire pavement. It is likely that the depressed
areas have settled as far as they are going to, and now that you've
adjusted surface level accordingly, they won't settle any further.
I'm glad I don't live in your part of the world, with all
those sunken driveways, dug-up paving jobs, iffy builders and
what-have-you. Maybe a few more people ought to have a look at my
webpage, and make sure they're getting a proper job done ;~)
Nick Maclaren
cormaic <cor...@NOSPAMTODAYTHANKStmac.clara.net> wrote:
>'Twas 26 Sep 1998 11:32:15 GMT, when the most noble nm...@cus.cam.ac.uk
>(Nick Maclaren) declared:
>>
>>I really am getting a little tired of being quoted out of context,
>>and even misquoted. I made a comment SPECIFICALLY about an amateur
>>building a patio, and there are damn good reasons for what I said.
>>One of the points that both Cormaic and you have missed is that there
>>are often important services running underneath the ground, and they
>>are often too shallow and rarely documented for older houses.
>
> You will grant that I have dug off more patios/driveways etc
>than your goodself, and I can tell you that services are not 'often
>too shallow', as you suspect.
Yes, I quite happily admit that, but I am afraid that you are being
VERY misleading. What you say is true for newish houses built
according to the regulations, where newish means after about 1850
in London, after about 1960 in most of the rest of the UK, and
not until about 1980 in the Highlands of Scotland. Yes, really.
> All utility contractors are obliged to maintain their
>equipment at a safe working depth. For water, this is taken as 900mm
>below ground level, for frost protection. Gas, electricity, telephone,
>and cable are not as strict. However, ALL utility contractors will
>come out to any pipe or cable exposed in the construction of a
>domestic driveway or patio and use their own labour to sink or renew
>the service, at a lower, safer depth.
Oh, really? Here are a few relevant points:
1) There were no building regulations in the UK outside London
until the Public Health Act 1875 and, even then, they came in very
gradually.
2) The 900 mm depth restriction was introduced quite recently
(1965?), and replaced a much shallower limit (2'?) after there had
been a lot of frozen pipes in one very hard winter.
3) During the housing boom of the 1950s, there were far too few
inspectors, and a LOT of houses were built that did not meet the
regulations. That is one reason that 1950s houses are regarded very
suspiciously by surveyors.
Virtually every older house where I have looked at the services (and
it is a fair number, for various reasons) has had at least one
shallower than 3' (900 mm), usually one shallower than 2' and some
have had one shallower than 1'. I have seen 6"!
Your remarks about the utility companies are interesting, but don't
correspond with my experience or that of most of the people I know.
In fact, the recently privatised water company sent me a leaflet
explicitly saying the opposite (and offering insurance to provide
the service you say comes for free.)
> I undertake approximately 200 domestic paving jobs each year.
>For the last year for which records are available, we had to call out
>the Electricity supplier once and BT on two occasions, on a turnover
>of 212 jobs. Thats 3/212 or 1 in 70 - not 'often'.
And how many of those houses had services installed before 1960?
>>Digging out 8-12" is precisely the right depth to risk damaging such
>>services without exposing them - I know several people who have had
>>their new drives dug up for this reason.
>
> Then that is shoddy work by the contractor, and your
>colleagues ought to claim against the contractors insurance. It is
>usually pretty easy for an experienced contractor to identify exactly
>where services run, and take the appropriate action. If unsure, the
>utility co's offer a 'dial-before-you-dig' service.
Oh, really! Ha, ha. And what about services to OTHER houses that just
happen to cross your property? Very common practice before the war;
I have two such pipes, and God alone knows what they carry (if
anything.) In any case, it has only been mandatory to keep those
records for a few decades, and older records are likely to be inaccurate,
incomplete or just plain absent. I have (in more than one case) had
a utility company wanting to relay a pipe ask ME where it ran, to
avoid having to dig exploratory trenches.
You are likely to get precisely nowhere claiming compensation from
a contractor if they cracked an undocumented pipe 18" down. They
haven't been negligent, and so it is YOUR problem, unless the
contract explicitly accepts liability for non-negligent damage.
Remember that the damage may show up only after a your or more,
especially if it is a sewage pipe.
And, while the utility companies MAY fix it for free, they will
leave one hell of a mess digging up your new driveway, and it is
YOUR problem to get it made good. Check on the law :-( And a
pox on the bloody Gas Board (now British Gas.)
Nick Maclaren
cormaic <cor...@NOSPAMTODAYTHANKStmac.clara.net> wrote:
>'Twas 23 Sep 1998 22:36:27 GMT, when the most noble nm...@cus.cam.ac.uk
>(Nick Maclaren) declared:
>>
>>You are clearly a modernist. You may be unaware that the traditional
>>way of laying paving bricks, slabs, crazy paving etc. is without any
>>form of mortar. If competently done, they don't shift.
>
> The traditional forms of paving, as you call the, have always
>relied on edges being fixed, often by sinking a keel stone or a series
>of them. And the use of lime-mortars, the forerunner of modern
>cements, is typical of many 'traditional' pavements.
Yes, you are right - I should have said A traditional, not THE
traditional. But edging does not imply mortar, if it is supported
both sides (e.g. by separating a patio from a lawn), and it is
very misleading to imply that modern cement is the successor to
lime mortar. What is normally referred to as cement (i.e. either
the material, or a 3:1 mix with sand) is VASTLY harder and more
adhesive than lime mortar.
> Despite your convictions, modernism does not equate with
>over-engineering. If your 'traditional' methods are so good, why are
>they not accepted practice throughout the construction industry, from
>Architects down to the lads on the tools?
One of the reasons that many traditional methods have been superseded
is that they are often labour-intensive, and nowadays labour is a
much higher proportion of the cost. That is not a constraint for
amateurs, in general.
> For home-use, your sandy soil might be fine, but would not be
>acceptable to my standards, nor on any proper paving contract. The
>Resident Engineer would chuck me off the site if I turned up with a
>load of sandy soil to lay the paving upon!
Absolutely. I didn't say anything different. If one isn't constrained
the official standards, one can measure the sand content and decide
what to do accordingly. You, as a contractor, do not have that option.
> I refer you to BS 6717 and BS 7533 which lay out a design
>procedure for the construction of flexible pavements from concrete
>block pavers. Basically, a sub-base, a bedding layer, and the
>surface layer. Blocks laid on bare earth, no matter how sandy, is not
>the accepted standard of construction.
You might be surprised at what I have on a chest of drawers in my
bedroom :-) But that isn't the point.
The key word in your paragraph is "flexible". One extremely common
myth that is fostered by many books on garden construction for
amateurs is that using cement makes a longer-lasting job. In this
case, one recommendation is to lay the sub-base, cover that with an
inch or so of concrete and cement the blocks/slabs/etc. to that. In
fact, I got a couple of quotes for my drive that were going to do
precisely that.
And it was in response to that myth that I made my original posting
replying to the original question.
cormaic
(Nick Maclaren) declared:
8<---S-N-I-P--->8
> What is normally referred to as cement (i.e. either
>the material, or a 3:1 mix with sand) is VASTLY harder and more
>adhesive than lime mortar.
Yep! That's why it's used. :~)
>One of the reasons that many traditional methods have been superseded
>is that they are often labour-intensive, and nowadays labour is a
>much higher proportion of the cost. That is not a constraint for
>amateurs, in general.
No-one wants to pay a mason to cut individual cube setts from
a block of granite, now that we can mass-produce concrete equivalents,
or have machinery split the stone for us. But even an amateur does not
want to go to this sort of extreme, unless they are very, very bored.
The amateur should take advantage of the latest methodology.
The modern materials are often superior to their antiquated
predecessors, while construction practices have been constantly
refined to produe a 'best ever' version. By using this approach, the
labour required can be kept to a minimum, which is good for us
professionals, and for the home DIYer :~)
8<---S-N-I-P--->8
> If one isn't constrained
>the official standards, one can measure the sand content and decide
>what to do accordingly. You, as a contractor, do not have that option.
The number of properties with a workable, sandy soil must be
only a small percentage of the total. What is a 'sandy soil' to a
gardener or soft-landscaper may not be 'sandy' enough for paving
purposes. If it's reasonable topsoil, better to dig it off and use it
as a growing medium, and import a clean, grit sand for the paving.
>
8<---S-N-I-P--->8
>
>The key word in your paragraph is "flexible".
Jargon Corner:
For the uninitiated, this is the most common type of block/brick
paving used in the UK. It does not imply the paving moves freely, but
that it is not fully rigid, as it would be if laid on a concrete bed.
>One extremely common
>myth that is fostered by many books on garden construction for
>amateurs is that using cement makes a longer-lasting job.
I would tend to agree with that, but that does not mean that
every piece of paving should be mortar- or concrete-bedded. Cement
allows us to use concretes, which is used to ensure that any free
edges to paving can be firmly anchored to the sub-grade.
>In this
>case, one recommendation is to lay the sub-base, cover that with an
>inch or so of concrete and cement the blocks/slabs/etc. to that.
That would be a rigid construction. For patios, the sub-base
is not required, for driveways the situation is different, depending
on the type of material being used for the surface. A sub-base *is*
essential beneath a driveway, but the type of sub-base is determined
by the chosen paving material.
>In
>fact, I got a couple of quotes for my drive that were going to do
>precisely that.
I wouldn't be happy with the spec. you quote above for a
driveway, unless the sub-base was a minimum 100mm thick concrete with
appropriate movement joints, and full mortar joints between the paving
units. That would be a rigid construction.
For domestic situations, I prefer a flexible construction,
with a stone sub-base, grit sand bedding layer and paving units
specifically designed for flexible paving, jointed with a specific
sand. Most block paving falls into this category, and so does some
types of flags/slabs, but not all. For example, riven type flags/slabs
with uneven edges are not suitable for sand jointing and need to be
mortar jointed.
--
cormaic - paving pages at http://www.tmac.clara.net/paving2.htm
Culcheth - Last Updated on September 27th 1998
cormaic
(Nick Maclaren) declared:
>Yes, I quite happily admit that, but I am afraid that you are being
>VERY misleading. What you say is true for newish houses built
>according to the regulations, where newish means after about 1850
>in London, after about 1960 in most of the rest of the UK, and
>not until about 1980 in the Highlands of Scotland. Yes, really.
The absence of regulations was not used as an excuse to bury
everything just beneath the surface, there is a principal of common
sense involved. Bear in mind that in older properties, the srvices
were installed many years after original construction.
If a house was built in 1850, it is pretty unlikely that the
electric cable was installed at the same time. More likely 50-70 years
later.
8<---S-N-I-P--->8
>
>Virtually every older house where I have looked at the services (and
>it is a fair number, for various reasons) has had at least one
>shallower than 3' (900 mm), usually one shallower than 2' and some
>have had one shallower than 1'. I have seen 6"!
Only the water service is likely to be at 900mm depth, and I
too have seen shallow services, but the point is that they are not as
common as you seem to think.
>
>Your remarks about the utility companies are interesting, but don't
>correspond with my experience or that of most of the people I know.
>In fact, the recently privatised water company sent me a leaflet
>explicitly saying the opposite (and offering insurance to provide
>the service you say comes for free.)
I suppose the service differs around the country with
different water co's. But the central point remains that, if a service
is exposed during any construction project, the relevant utility co
will come to inspect and assess.
>
>> I undertake approximately 200 domestic paving jobs each year.
>>For the last year for which records are available, we had to call out
>>the Electricity supplier once and BT on two occasions, on a turnover
>>of 212 jobs. Thats 3/212 or 1 in 70 - not 'often'.
>
>And how many of those houses had services installed before 1960?
I flicked through the files to jog my memory, so I can tell
you that of the 212 projects, 91 were on pre 1960's property, and of
the call-outs, one was 1950's bungalow (BT), one a 1960's detached
(Electric) and one a 60's or early 70's bungalow (must be something
about bungalows!)
8<---S-N-I-P--->8
>
>Oh, really! Ha, ha. And what about services to OTHER houses that just
>happen to cross your property? Very common practice before the war;
>I have two such pipes, and God alone knows what they carry (if
>anything.) In any case, it has only been mandatory to keep those
>records for a few decades, and older records are likely to be inaccurate,
>incomplete or just plain absent. I have (in more than one case) had
>a utility company wanting to relay a pipe ask ME where it ran, to
>avoid having to dig exploratory trenches.
...and your point is?
>
>You are likely to get precisely nowhere claiming compensation from
>a contractor if they cracked an undocumented pipe 18" down. They
>haven't been negligent, and so it is YOUR problem, unless the
>contract explicitly accepts liability for non-negligent damage.
>Remember that the damage may show up only after a your or more,
>especially if it is a sewage pipe.
So what should the general public do, Nick? Never have any
paving work undertaken just in case an undocumented service gets
damaged? And BTW, most reputable contractors offer a 5yr guarantee on
their work. :~)
>
>And, while the utility companies MAY fix it for free, they will
>leave one hell of a mess digging up your new driveway, and it is
>YOUR problem to get it made good. Check on the law :-( And a
>pox on the bloody Gas Board (now British Gas.)
You really do have hell of a lot of trouble with your
contractors and others working on your property. Could it be something
to do with your attitude that pisses them off?
cormaic
<k...@scarboro.demon.co.uk> declared:
>
>But weren't you advocating using concrete as a base?
Not in all cases, and for certain types of construction only. The
original question was about the use of mortar as a jointing medium for
flagged/slabbed areas. As I've said in a previous post, in most cases
patio flags ought to be mortar jointed.
>If it cracks, why
>does it make a good base?
When properly laid, concrete doesn't crack, or at least not as
often. A concrete sub-base can only be designed once the site
conditions and the anticipated loadings are known. Movement joints and
fibre- or steel-reinforcement will help eliminate potential cracks in
a concrete sub-base or slab.
Chris French
ODAYTHANKStmac.clara.net> writes
>'Twas 26 Sep 1998 20:16:57 GMT, when the most noble nm...@cus.cam.ac.uk
>(Nick Maclaren) declared:
>
>>
>>it is a fair number, for various reasons) has had at least one
>>shallower than 3' (900 mm), usually one shallower than 2' and some
>>have had one shallower than 1'. I have seen 6"!
>
> Only the water service is likely to be at 900mm depth, and I
>too have seen shallow services, but the point is that they are not as
>common as you seem to think.
>>
>>Your remarks about the utility companies are interesting, but don't
>>correspond with my experience or that of most of the people I know.
>>In fact, the recently privatised water company sent me a leaflet
>>explicitly saying the opposite (and offering insurance to provide
>>the service you say comes for free.)
>
> I suppose the service differs around the country with
>different water co's. But the central point remains that, if a service
>is exposed during any construction project, the relevant utility co
>will come to inspect and assess.
>>
To leap in here, don't forget that not all services are in the same
position re. responsibility.
The water pipe on my property is my responsibility, but the elec. cable
and gas pipes, and telephone are the responsibility of the utility co.
up to the meter, master socket or whatever.
So I guess you could both be right :-)
--
Chris French and Helen Johnson
Leeds
Email address valid for at least two weeks from posting
Duncan Russell
not putting down current practice, but I thought what the heck I rather be
reading the gardening threads, calm down one and all, please.
Pete Marrow
Goodness me. I posted the original question - so you can blame me for any of
incendiary thread that followed !
What a stooshie. Thank you for all the advice one and all. Having been
elsewhere for a while, I had to use Deja News to read the responses as they
don't seem to be cached for me to read them with
my normal newsreader.......
I had a minor heart operation last year (is any heart operation minor?) so
wish to avoid strenuous heavy lifting type work in the
garden, even though lots of more gentle exercise is to be positively
encouraged. Hence the question as to whether cementing was needed for the
planned paved area.
I have been sent some Merkin gardening mags by my beautiful Utahn
fiancee, and they have illustrations of paved (and bricked) areas that
were done with no cement but are tightly confined within treated timber with
kiln dried sand brushed over the top.
I am off to read the cormiac pages now to see how a modern professional does
these things. Unfortunately I don't have large wodges of dosh to pay for a
landscape gardener....
Anyone else see todays Scotsman newspaper about Charlies bouncy bits and a
certain professional gardener turned novel writer?
----------------------------------------------------------------------------
Pete Marrow
e_mail: P.Ma...@bgs.ac.uk
http://www.gorp.com/gorp/activity/scottish_ff_faq.htm
Alan J Holmes
>necessary for a paved area. As a Garden Designer I have to side with Cormaic.
>The most certainly are! A fair number of my design jobs have involved
>rebuilding what I term a "jobbing builders patio" laid by the cheapskate
>builder who built the extension\conseraatory\house using minimal foundations
>very much like the method advocated by Nick instead of the
>excavation\sub-base\base\paving method advocated by Cormaic. Re-building has
>been necessary bacause of the ski slopes rapidly forming as the garden soil
>beneath the paving setles. Yes it is possible to get away with minimal
>foundations but ONLY on undisturbed soil with minimal oranic matter content.
>I have a real time experiment running on this at the moment. A few months ago
>I designed and contract managed a new driveway for a house around the corner.
>A few doors away another house had a drive laid at the same time, for that
>job 4 guys turned up, stripped off some of the existing concrete drive
>surface, Whacked the rest into the soil using a plate vibrator, threw down
>2in of sharp sand put the blocks on top, and haunched edging blocks with no
>other footing than the said sand. Joint were filled with builders sand. Job
>took 1 week!
>For my job, two guys dug out to 200mm, set edging blocks on concrete strip
>footing,laid 100mm hardcore (Mot type I, for the technically minded), laid
>50mm sharp sand and compacted with plate vibrator before laying blocks and
>filling joints with kiln dried sand. Duration of job: 4 days.
But, the original article was discussing the merits of
_patio_ laying which does not have the same level of
traffic as a driveway. So, what is vital for one job is
not neccessarily _essential_ for the other.
Our, poorly laid, by cormiacs standards, patio has many
cracks in the joints, mostly filled with very pretty
plants which have been transported there probably by our
feathered friends, this would not have happened if the
patio had been laid by a professional of cormiacs
standards, but it suit us very well.
As I said to a neighbour who objected to my 60 foot
amateur radio mast, 'beauty is in the eye of the
beholder'!(:-)
I don't really think this discussion is getting anywhere,
I have respect for the methods used by both 'antagonists'
who each have a different approach to life and this
particular job, I'm very happy with what I have laid,
cormiac would probably have a heart attack if he saw it!
>Now, less than 6 months later one of these driveways has weed growing in ever
>widening joints between the bricks and shows clear depressions where the car
>runs and the edging had moved. The other is perfectly level and weed free. No
>prizes for guessing which is which!
Curiously, my driveway which has been covered with tarmac
over a concrete base has more moss growing on it than in
the grass at teh back of the house, how do I get rid of
that, and make sure it doesn't grow again?
>Depends what you want I suppose, but I guess most people want something that
>will last and look good for a long time. For that Cormaic's advice on footings
>and cement is to be commended.
As I've said, what looks good to one, may not
neccessarily look good to another, I can't imagine what a
sterile patio would look like, it certainly wouldn't suit
me.
Went to one of those 'Open Gardens' yesterday, it had a
patio laid with proper stone flags, fairly even, large
gaps in some places, but had an abundance of plants growing
through and over it, it looked wonderful.
Obviously not laid to cormiacs standards!
Alan J Holmes
cormaic <cor...@NOSPAMTODAYTHANKStmac.clara.net> wrote:
>'Twas 26 Sep 1998 11:32:15 GMT, when the most noble nm...@cus.cam.ac.uk
>(Nick Maclaren) declared:
>>I really am getting a little tired of being quoted out of context,
>>and even misquoted. I made a comment SPECIFICALLY about an amateur
>>building a patio, and there are damn good reasons for what I said.
>>One of the points that both Cormaic and you have missed is that there
>>are often important services running underneath the ground, and they
>>are often too shallow and rarely documented for older houses.
> You will grant that I have dug off more patios/driveways etc
>than your goodself, and I can tell you that services are not 'often
>too shallow', as you suspect.
In my house they were, most of the drains were laid within a few,
as little as 3, inches below the surface.
The gas pipe entering the premises were only about 6
inches below the surface, water a little deeper.
Because of some neglect by the local authority the drains today
are only about 6 inches below the surface today, having been relaid
following the change from cesspit to mains drains, some idiot
read a flydirt on the drawing when the road was made up and the
main installed, just 30 inches below the surface of the road, and
my driveway falls away from the road, so I had a lot less than 18
inches before I could connect about 60 feet away.
At the end of our road, the main falls about 5 feet to meet the
main in the major road!
Peter Matthews
<Jud...@nanime.demon.co.uk> writes
>Snipped
Normally laying slabs directly on to soil provides a shelter for ants,
worms, beetles and fly lavea, who will eventually cause the slabs to
shift. In addition the seeds of weeds get between the cracks and
germinate in the soil causing further movement of the slabs.
The only place I have know slabs to stay put is on sandy well drained
soils where they are exposed to the sun, which is the case described by
Nick.
Regards
--
Peter Matthews
ia...@teleord.co.uk
"Pete Marrow" <P.Ma...@bgs.ac.uk> that wrote:
> Anyone else see todays Scotsman newspaper about Charlies bouncy bits and a
> certain professional gardener turned novel writer?
For those of us who can't get their hands on a copy, see www.scotsman.com
for a full interview with charlie, and one with Mr. MacGreg, er, sorry,
Titchmarsh.
Adios Amigos!
Ian.
--
This post does not reflect the opinions of Whitakers.
Judith Lea
Matthews <pe...@mattsimm.demon.co.uk> writes
>In article <NvBK0AAk...@nanime.demon.co.uk>, Judith Lea
><Jud...@nanime.demon.co.uk> writes
>
>>Snipped
I don't know what I said as it was snipped!
--
Judith Lea
Kay
>It could have been aliens, the CIA, or maybe even
>"Pete Marrow" <P.Ma...@bgs.ac.uk> that wrote:
>
>> Anyone else see todays Scotsman newspaper about Charlies bouncy bits and a
>> certain professional gardener turned novel writer?
>
>For those of us who can't get their hands on a copy, see www.scotsman.com
>for a full interview with charlie, and one with Mr. MacGreg, er, sorry,
>Titchmarsh.
Not quite the same topic, but there's an article on diascias by Chris
Boulby's brother Will in the current issue of Northern Gardener
--
Kay
k...@scarboro.demon.co.uk
Pau...@my-dejanews.com
xxx...@brunel.ac.uk (Alan J Holmes) wrote:
>
> Went to one of those 'Open Gardens' yesterday, it had a
> patio laid with proper stone flags, fairly even, large
> gaps in some places, but had an abundance of plants growing
> through and over it, it looked wonderful.
>
> Obviously not laid to cormiacs standards!
I wouldn't like to speak for Cormaic (BTW saw the other thread Epicormic and
thouhgt some wit had renamed this thread) but, even a patio with wide soil
filled gaps to give a aged or cottage effect needs to be properly laid on
proper foundations if the slabs are not to move. The planting pocekts are
just as constructed as the rest of the paving!
BTW ref another part of this thread, not putting in foundations becauuse you
are afraid of hitting services is a little like putting up a shelf with glue
as you are afraid of drilling into cables! (;-))))
PK
Nick Maclaren
Jon Rouse <rou...@it.postoffice.co.uk> wrote:
>cormaic wrote:
>
>> So what should the general public do, Nick? Never have any
>> paving work undertaken just in case an undocumented service gets
>> damaged? And BTW, most reputable contractors offer a 5yr guarantee on
>> their work. :~)
>
>used a contractor for my roof who had good references and was a member of the
>national federation. His organisation was poor but his workers were good, and
>the end job (which I closely supervised) was good. However that didn't stop
>him going out of business, and the twenty year guarantee he offered (and which
>we never received) isn't worth the paer it isn't written on.
The other problem is with consequential losses. There was someone
that I heard of where a contractor cracked a water pipe, but not enough
to show immediately. As the house was metered, the first symptom was
a very large water bill. This was queried, the problem was eventually
located, and fixed (for free) by the contractor. The householder was
still arguing about who should pay the water bill, when the next one
came in - and, because the crack had developed, it was HUGE!
I don't know whether that bill could be claimed from the contractor,
but I doubt it, because there was no negligence involved. It was
simply a too-shallow and undocumented water pipe.
>> You really do have hell of a lot of trouble with your
>> contractors and others working on your property. Could it be something
>> to do with your attitude that pisses them off?
>
>Everybody I know has trouble with contractors. I don't doubt you do a good
>job, but I'm afraid you are in a minority (possibly of one).
That is my experience, too, but I seem to have less serious trouble
than most of my friends - perhaps because I insist on making things
clear at the start. Many of my horror stories are from relatives
and friends, often when I have been asked for my advice on how to
sort out the fiasco.
For example, NEVER believe a verbal promise if it conflicts with a
contract or a statement that a third party will fix something up for
free without checking. Also, always check that a contractor is aware
of local conditions and potential problems.
One of the contractors that I didn't choose made the statement that
all services in my area were at least 900 mm down. Well, I had
inspected the water and sewage (being accessible) and both were
about 550. I chose the one who said that they were usually at least
a couple of feet down, but they would take extra care as mine was an
older house.
Victoria Clare
>To leap in here, don't forget that not all services are in the same
>position re. responsibility.
>
>The water pipe on my property is my responsibility, but the elec. cable
>and gas pipes, and telephone are the responsibility of the utility co.
>up to the meter, master socket or whatever.
And I too will rashly leap - there are still not a few places where
septic tanks are still the norm, and the water company has no
involvement with sewage pipes. Pipes to old septic tanks can go in
very odd places, though you can often tell if they are near the
surface from the luxuriant greenness of the foliage above. . .
I was rather alarmed the other day when I had a gas leak from the
pipes in the front garden - in my 1970's semi. A gang of blokes from
British Gas turned up, removed an (unconcreted) paving slab by the
front door (which I had previously supposed was provided for the
convenience of my pot of lavender), and proceeded to fix the pipe less
than a spade's depth immediately below.
I have shelved my plan for a new shrup in that area, and instead
planted sedums with nice shallow roots :-)
The house also has privately owned water pipes directly underneath it,
and I was warned by the surveyor when we moved in that there seemed to
be no records of exactly where these went but I am assuming that it's
nowhere I can hit them with a spade until proved otherwise! I did
find an old pipe when I dug my (c2ft deep) pond, but luckily it proved
to be not in use.
Victoria
--
vict...@nogrod.u-net.com
http://www.nogrod.u-net.com/
--
John Neale Baraclough
Off topic but never mind. We have a private water pipe 3/4 of a
mile long which crosses several farmers' land. When it was installed
a carefully measured map of its path was made, accurate to the inch,
water pipe drawn in ink . Last time we needed it we found the 20 year
old map must have been exposed to too much light and the 20 year old
ink had become invisible.See how easy it is to lose track of these things!
Janet
--
/* Janet & John Baraclough *\
r...@zetnet.co.uk - Janet
\* j...@zetnet.co.uk - John */