How to treat really old beams?
tom.ha...@gmail.com
8"x8" (though some are round and some are larger) and there's about
35m visible. I'm pretty sure they are mostly elm.
So far, I've stripped the limewash that was on some of them, gone at
the really wood-wormy ones with a wire brush, and treated them all for
woodworm. I don't think there was any active woodworm, but better safe
than sorry. The oldest and worst affected beams were alarmingly soft
until I got to the heartwood, which is solid!
So, I'd like to treat them with something which would stabilise the
slightly flaky surface of the wood-wormy beams, but would still look
OK on the unaffected beams. Any suggestions?
T
The Natural Philosopher
but the punk wood will always look a bit plasticky afterwards.
best to do them all the same. Then sand a bit.Don't attempt a
penetrating stain afterwards though..if you want colour, use a coloured
varnish (also called stains of course!)
Stuart Noble
Briwax is often used for this sort of thing
meow...@care2.com
ask on the period property uk forum, they actually know
NT
Stuart Noble
If you know that they know, why don't you just tell us?
The Natural Philosopher
Because he doesn't and nor do they?
For some reason he's trying to shill the site. Probably gets a pay per
click income off it.
Anna Kettle
<stuart...@ntlworld.com> wrote:
>meow...@care2.com wrote:
>> tom.harri...@gmail.com wrote:
>>> I've got some very old beams in my house. They're approximately
>>> 8"x8" (though some are round and some are larger) and there's about
>>> 35m visible. I'm pretty sure they are mostly elm.
>>>
>>> So far, I've stripped the limewash that was on some of them, gone at
>>> the really wood-wormy ones with a wire brush, and treated them all for
>>> woodworm. I don't think there was any active woodworm, but better safe
>>> than sorry. The oldest and worst affected beams were alarmingly soft
>>> until I got to the heartwood, which is solid!
>>>
>>> So, I'd like to treat them with something which would stabilise the
>>> slightly flaky surface of the wood-wormy beams, but would still look
>>> OK on the unaffected beams. Any suggestions?
I expect that there are several ways to do it but this is the method I
use because I have infinite amounts of lime putty sitting around the
place
Spray with lime water. Allow to soak in. Repeat until bored
Lime water is made by ...
Mix lime putty with water to make a white liquid somewhat like milk.
This is called limewash albeit a rather thin limewash
Allow to settle and then carefully decant off the clear liquid
(limewater) from the top. Put it into a handspray and start spraying
As limewater is clear it doesnt change the colour of the wood but it
consolidates the surface basically by tying it together with
limestone
If you dont have lime putty but do have fresh hydrated lime then use
that instead but stir the limewash a few times over a couple of days
before allowing it to finally settle out
If you want to be able to use the spray again then rinse it well when
you have finished. Limestone is good at clogging up the spray nozzle
too
Anna
Stuart Noble
But he's just stripped the limewash off....
meow...@care2.com
Because you and stuart always show up on these threads giving
inappropriate advice.
NT
The Natural Philosopher
Stuart Noble
Try explaining yourself for once.
meow...@care2.com
> Well you would say that, wouldn't you?
its no secret thats what I think of your advice on this one topic.
Enough people have followed such outdated advice for the resulting
damage to be a known deal. That is precisely why the experts in the
field no longer recommend the approaches that were common decades ago.
With respect, this topic and other PP topics come up over and over and
over, and have been answered over and over and over. I'm not an
automatated typewriter, if the OP wants to help themselves with a
little basic reading they will. I've shown them where they can find
it. If you want me to get into the same old territory with you 2 time
after time, I really dont see the point. You 2 are too lazy to go read
up on this stuff, and that wont change.
NT
tom.ha...@gmail.com
> Anna Kettle wrote:
> > On Sat, 18 Apr 2009 09:40:23 GMT, Stuart Noble
Only three of the beams were limewashed - many layers of it and very
flaky, so it had to come off. I do happen to have plenty of lime lying
around, so I shall mix up some hydrated lime and try it out on a small
area. If it works, it'll be a very cheap solution!
Thanks
Tom
ali
Dear Tom
It is now too late but for any others who might be reading, my advice
would have been "Don't" (treat that is) and to leave it alone
I certainly would not recommend any resin which would act as a
possible condensation trap (unlikely but possible) and would most
likely stop vapour movement
I liked Anna's idea.
I would have also done a check that the amount of heart wood in the
tension zone in the middle of the beam was sufficient for its
structural purpose
Chris
Stuart Noble
>> Try explaining yourself for once.
>
>
> With respect, this topic and other PP topics come up over and over and
> over, and have been answered over and over and over. I'm not an
> automatated typewriter, if the OP wants to help themselves with a
> little basic reading they will. I've shown them where they can find
> it. If you want me to get into the same old territory with you 2 time
> after time, I really dont see the point. You 2 are too lazy to go read
> up on this stuff, and that wont change.
PP is not a seat of learning. It's a commercial self-interest group with
a slightly religious flavour. Suggest it by all means, but it is the
height of bad manners to re-direct people there.
Anna Kettle
wrote:
I shall mix up some hydrated lime and try it out on a small
>area. If it works, it'll be a very cheap solution!
But not quick. Remember that this is is lime so takes time to set
Anna
meow...@care2.com
> >> Try explaining yourself for once.
> >
> >
> > With respect, this topic and other PP topics come up over and over and
> > over, and have been answered over and over and over. I'm not an
> > automatated typewriter, if the OP wants to help themselves with a
> > little basic reading they will. I've shown them where they can find
> > it. If you want me to get into the same old territory with you 2 time
> > after time, I really dont see the point. You 2 are too lazy to go read
> > up on this stuff, and that wont change.
>
> PP is not a seat of learning.
it is as much as here, and like ukdiy it has its own strengths
> It's a commercial self-interest group with
Its not a commercial group at all. The people involved have no more
tie with the hosting company than we have with google.
And whats a self interest group? :)
> a slightly religious flavour.
Thats lame. They have views that differ from yours, and can back them
up.
> Suggest it by all means, but it is the
> height of bad manners to re-direct people there.
Last time I checked a link to relevant expertise wasnt bad manners.
I hope that when it comes to the maintenance of PPs, people take time
to read both, then they'll avoid rushing in with the wrong actions, as
too often happens. And where advice differs they'll understand why,
and hopefully come away knowing for themselves what line to follow.
Many that have failed to take the time have lost either historic
fabric, and too frequently a lot of money, later.
NT
The Natural Philosopher
> Stuart Noble wrote:
>>>> Try explaining yourself for once.
>>>
>>> With respect, this topic and other PP topics come up over and over and
>>> over, and have been answered over and over and over. I'm not an
>>> automatated typewriter, if the OP wants to help themselves with a
>>> little basic reading they will. I've shown them where they can find
>>> it. If you want me to get into the same old territory with you 2 time
>>> after time, I really dont see the point. You 2 are too lazy to go read
>>> up on this stuff, and that wont change.
>> PP is not a seat of learning.
>
> it is as much as here, and like ukdiy it has its own strengths
>
>
>> It's a commercial self-interest group with
>
> Its not a commercial group at all. The people involved have no more
> tie with the hosting company than we have with google.
>
> And whats a self interest group? :)
>
>
>> a slightly religious flavour.
>
> Thats lame. They have views that differ from yours, and can back them
> up.
>
Not unless you take the religious view that there is some externally
imposed absolute morality with respect to old buildings.
It all depends in what you wish to preserve, and for what purpose.
There is a huge gulf between approaching it as a museum conservation
job, and merely wishing to retain a period flavour in a modern low
energy, and usable. living space.
Without identifying the desired result first, there can be no 'right' or
'wrong' way to approach such a task.
Anyone who has actually studied really old house will know that they
have been subject to one rebuild and extension after another: in te 17th
century it was fashionable to remove wattle and daub, and infill with
brick between timbers.and build brick chimney stacks where there had
been smokeholes..
A timber frame cottage was of course the equivalent of a Wimpey home
today - cheap, not very good, and in Victorian times, definitely
something to be covered up and made more habitable.
It is the curse of nostalgia that today, everything more than 50 years
old is held to be so precious it must be preserved in what ever
ridiculous state it is now, forever.
Personally, if you want to live in a decent pegged joint oak frame
house with lime plaster and so on, then buy a tatty old 50's bungalow,
demolish it and build one.
You can then make sure that tucked in its walls, build on substantial
foundatinons that wont subside or heave, is a damp proof course, and
some insulation. And all the wires and pipes you want to add the
ridiculously un 17th century lights and central heating.
Ok the BCO wont let you make a ladder as main access to the hayloft, or
bedrooms as we would call them, but that's the price you have to pay.
OTOH if you want to spend three times as much restoring and living in a
museum that requires three times as much energy input and ventilation to
keep it dry and free from rot - it's your choice. Just don't foist it on
the rest of us as the 'only proper way' to approach the problem.
Frankly, there are a million ways to treat fluffy punky bemas, from
removing them and burning them and replacing with RSJ's to using any one
of a number of stabilisation techniques. It depends on what you want to
end up with.
meow...@care2.com
I very much agree with your sentiment that there are differing aims,
and of course differing resource levels of owners, and I think thats
too often overlooked. But that does not mean there are no wrong ways.
Each way has its own results, and unfortunately the cement/waterproof/
dpc approach with historic properties has caused too many owners too
much money to be an approach still worthy of recommending.
The reality is that the great majority of old houses now in poor
condition were designed in a way that worked, and still works today if
a suitable approach is taken. The end results of some suggestions I
see on ukdiy are all too familiar. And thats one of the strengths of
the pp forum, they are familiar with the end results of those outdated
maintenance methods and the damage they have caused.
NT
The Natural Philosopher
together, produce a result that is not what is desired.
However, to take ONE element - say waterproof rendering - and call it
'wrong' is just stupid. It ios not WRONG, it is just that it has to be
part of an overall different approach, as I have said many times.
Damp control is no more than keeping humidity below a certain level.
You can tackle it two ways, by allowing it to get out faster, or
stopping it getting in so fast.
There is nothing wrong with e.g. waterproof render if the damp is
getting in via driving rain. Its if its getting in another way, and you
are relying on a breathable surface to let it get OUT, that it is
inappopriate.
Likewise the use of 'soft' mortar is not necessarily appropriate either:
You can build a house to accomodate movement, or you can snsure that it
doesn't move at all.
Again the key point is to keep the actual movement below what the
techniques used can accomodate..
So e.g. building a modern extesnion onto an old house is a simple
exercise in cost benefit: whether it's going to cost more to stabilise
the existing by e.g. concrete underpinning, or build the new as sloppily
and old fashioned as the old, able to take a few cm of movement without
cracking away..
Neither approach is wrong. What is wrong is the mixture. Abutting a
rigid well found structure against a flexible ill-found one is asksing
for trouble.
.
> The reality is that the great majority of old houses now in poor
> condition were designed in a way that worked,
That is actually a contradiction in terms. Most old houses that are
gone, are gone because the cost of repair of some pretty shabby
construction exceeded the cost of replacement: Most old houses that are
in a poor state of repair are that way because the cost of maintenance
was too high, or the cost of heating them was too high and they weren't
built very well to begin with.
You have to take a view on what you want to do with an old property. The
average life of a house is about 120 years by and large. With a major -
really major - refurb every 50-60 years. That's not to say that they
will not last much longer if looked after, more that the conditions they
were built for render them pretty inappropriate for the use they need to
be put to after 120 years, or even 60..
You just need to look no further than the number of barn conversions and
urban warehouse developments turning essentially industrial buildings
into bijoux des rezzes, that has gone on..and even churches and chapels..
The only thing I would say about those is that they are in general
slightly less hideous than the new stuff that has been and still is put
up by property developers looking to turn a fast buck.
> and still works today if
> a suitable approach is taken.
Yeah, like keeping a chimney open and leaving all the draughts in place
and throwing money into heating. An open fire gets rid of huge amounts
of damp from a place, and a huge amount of heat goes up the chimneys
too. Fine if you can afford a parlour maid to set all the fires first
thing...
OTOH of you are in the business of trying to pull your carbon footprint
down, they need serious treatment throughout. Energy efficiency implies
either very extensive heat recovery systems, or low ventilation rates.
Breathable hoses don't gybe with high insulation levels either. The
moment you make the interior cosy, you have much colder walls, outside
the insulation, from which water wont so readily evaporate.
Old houses were not designed for central heating. Period. Or electricity
or plumbing, either.
If you want modern standards of heating and comfort, you have to
redesign them. Or throw money at them. Whether you throw money into
redesigning them, or heating them, is an individual decision. As is how
far you modify them to achieve sensible standards of living, and ongoing
costs, whilst preserving whatever aspect it is you feel you want to
preserve.
My old house had a leanto extension on the back, that had been opened up
to make a bigger room. The rearmost section of it comprised what at a
glance looked like an oak post and an oak beam going across the back of
the original part. Only when I demolished it did I discover it was
actually an 8x8 softwood (could have been an RSJ) that had been encased
in some old oak floorboards..and the black painted beams turned out to
be an odd assortment of timbers, some oak, but an awful lot of patched
in bits of what appeared to be quartered pine poles..the whole structure
was rotten to the core with damp..some having got in at soffit level,
some rising out of the exceptionally damp clay, where a pool of water
was found under the raised floors.
It wasn't a pretty house, it had been totally buggered, and was
thoroughly inconvenient. It got the chop. I built a new oak framed house
instead, that looks like it is a conversion/refurb. Most people think
its several hundred years old..in part..
I like oak, I like beams, I like old fashioned inglenook fireplaces
built out of tudor brick. I also like heating bills that don't upset the
bank manager, a decent kitchen, underfloor heating and bathrooms to
wallow in. I don't like the smell of damp and draughts. I achieved my
target.
Cost a fortune, but its a nice house. Nostalgia, is expensive.
Frankly, most of the stock of house built between 1880 and 1950 could
probably be better torn down, and replaced, if only the developers had
more than a half pounce of imagination and flair between them. And save
a huge amount on heating bills. If I've seen one row of victorian two up
two downers with a kitchen/bathroom extension on the back, I've seen a
thousand, If I have seen one street of bow windowed demi-tiled 30's
houses with single brick construction, and stained glass about the
doorways and tiled porches I've seen a thousand..
Trash em I say. All bar a representative few. Ugly, badly built, near
the end of their useful lives, and totally useless and energy
inefficient an unsuited for modern living.
Thst what the Victorians and Edwardians did to all the ramshackle
country hovels that no doubt you would drool over. Used to be one near
where I lived, on the fens. No water, no toilet, no electricity, no
access road, and just about all that was left was a central brick
chimney, and a collapsing structure of rotten oak beams. Overgrown with
brambles. Would have cost a fortune to put services into, although the
location might have made it worth while. That old fen used to have nigh
on a thousand people living on it, or off it, 100 years ago. five pubs,
two churches..now its about three farms and about 50 labourers cottages
lived in by god knows who..
Times change, and housing has to change with it. People are not
prepared to live the way they lived 100 years ago, and no wonder..and
the houses designed for that era are not fit for purpose today. You may,
if you are middle class and affluent, take one and spend a lot of money
making it so, but the original inhabitants couldn't afford to.
meow...@care2.com
wrote:
And as I've said many times, the damage waterproof rendering causes is
now known. Thats basically the definiton of 'wrong'. Whats news here?
If you have a proposed method you think prevents the damage it causes,
either to brickwork, stone or timber frame, I'm all ears. I've a
feeling you don't though.
> Damp control is no more than keeping humidity below a certain level.
really, no. Attempts to control damp that cause expensive damage to
the fabric of a building are all too familiar.
> You can tackle it two ways, by allowing it to get out faster, or
> stopping it getting in so fast.
Another popular myth. Damp doesn't 'get in', the net flow of damp in
all houses is from interior to exterior. Think about it: we cook, we
breathe, we shower; if the net flow of damp werent from interior to
exterior the house would flood.
Assuming the house is maintained and water isn't pouring in somewhere,
then problems result when the outflow of damp is insufficient.
> There is nothing wrong with e.g. waterproof render if the damp is
> getting in via driving rain.
Why don't you go find out how it damages buildings.
> Its if its getting in another way, and you
> are relying on a breathable surface to let it get OUT, that it is
> inappopriate.
>
> Likewise the use of 'soft' mortar is not necessarily appropriate either:
> You can build a house to accomodate movement, or you can snsure that it
> doesn't move at all.
of course. Houses that do move do need soft mortar. People do
sometimes spend unreasonable amounts of money on underpinning without
good cause.
> Again the key point is to keep the actual movement below what the
> techniques used can accomodate..
>
> So e.g. building a modern extesnion onto an old house is a simple
> exercise in cost benefit: whether it's going to cost more to stabilise
> the existing by e.g. concrete underpinning, or build the new as sloppily
> and old fashioned as the old, able to take a few cm of movement without
> cracking away..
>
> Neither approach is wrong.
yes quite - I wish today's BR took that and more into account. Its not
so hard to do either.
> What is wrong is the mixture. Abutting a
> rigid well found structure against a flexible ill-found one is asksing
> for trouble.
> .
>
> > The reality is that the great majority of old houses now in poor
> > condition were designed in a way that worked,
>
> That is actually a contradiction in terms. Most old houses that are
> gone, are gone because the cost of repair of some pretty shabby
> construction exceeded the cost of replacement:
Why houses are gone is another topic, mainly down to higher density
redevelopment as population has increased. A house has to be in a hell
of a state before rebuild is cheaper than repair.
> Most old houses that are
> in a poor state of repair are that way because the cost of maintenance
> was too high, or the cost of heating them was too high and they weren't
> built very well to begin with.
They are mostly in a bad way with damp because inappropriate repairs
and maintenance approaches have been used. The idea that century old
buildings were faultily designed is just a persistent myth. Faulty
designs are rare.
> You have to take a view on what you want to do with an old property. The
> average life of a house is about 120 years by and large. With a major -
> really major - refurb every 50-60 years. That's not to say that they
> will not last much longer if looked after,
quite. Several times as long.
> more that the conditions they
> were built for render them pretty inappropriate for the use they need to
> be put to after 120 years, or even 60..
Really no. Look in any estate agent's window.
> You just need to look no further than the number of barn conversions and
> urban warehouse developments turning essentially industrial buildings
> into bijoux des rezzes, that has gone on..and even churches and chapels..
I dont think barn conversions tell us much about the ability of old
houses to meet modern needs. They're old barns, not old houses.
> The only thing I would say about those is that they are in general
> slightly less hideous than the new stuff that has been and still is put
> up by property developers looking to turn a fast buck.
yup :)
> > and still works today if
> > a suitable approach is taken.
>
> Yeah, like keeping a chimney open and leaving all the draughts in place
> and throwing money into heating. An open fire gets rid of huge amounts
> of damp from a place, and a huge amount of heat goes up the chimneys
> too. Fine if you can afford a parlour maid to set all the fires first
> thing...
There are rather more sensible methods than that. You propose a straw
man there.
> OTOH of you are in the business of trying to pull your carbon footprint
> down, they need serious treatment throughout. Energy efficiency implies
> either very extensive heat recovery systems, or low ventilation rates.
Just insulation and draughtproofing works pretty well. If you want to
take it further HRV is far from expensive.
> Breathable hoses don't gybe with high insulation levels either. The
> moment you make the interior cosy, you have much colder walls, outside
> the insulation, from which water wont so readily evaporate.
I'm unclear if youre describing interior, exterior or cavity
insulation. All 3 work fine on old houses, if done right. The large
number of all 3 in satisfactory use demonstrates that.
> Old houses were not designed for central heating. Period. Or electricity
> or plumbing, either.
>
> If you want modern standards of heating and comfort, you have to
> redesign them. Or throw money at them.
There is just no basis for such a claim. Obviously at some point they
got heating and electricity, just as a new build does on day 1.
> Whether you throw money into
> redesigning them, or heating them, is an individual decision. As is how
> far you modify them to achieve sensible standards of living, and ongoing
> costs, whilst preserving whatever aspect it is you feel you want to
> preserve.
I've seen quite a lot of old houses, and very rarely do they need
redesign. I don't know why you think they do.
> My old house had a leanto extension on the back, that had been opened up
> to make a bigger room. The rearmost section of it comprised what at a
> glance looked like an oak post and an oak beam going across the back of
> the original part. Only when I demolished it did I discover it was
> actually an 8x8 softwood (could have been an RSJ) that had been encased
> in some old oak floorboards..and the black painted beams turned out to
> be an odd assortment of timbers, some oak, but an awful lot of patched
> in bits of what appeared to be quartered pine poles..the whole structure
> was rotten to the core with damp..some having got in at soffit level,
> some rising out of the exceptionally damp clay, where a pool of water
> was found under the raised floors.
>
> It wasn't a pretty house, it had been totally buggered, and was
> thoroughly inconvenient. It got the chop.
Are you going to claim all old construction is like that? Every era
has its failed bodges, the old ones are usually long gone. That's one
of the plusses of old properties: regardless of modern build regs, a
century or more has proved their ability to work satisfactorily in
almost all cases. The level of complete failures on modern properties
will likely be higher than on the remaining stock of century old
builds.
> I built a new oak framed house
> instead, that looks like it is a conversion/refurb. Most people think
> its several hundred years old..in part..
>
> I like oak, I like beams, I like old fashioned inglenook fireplaces
> built out of tudor brick. I also like heating bills that don't upset the
> bank manager, a decent kitchen, underfloor heating and bathrooms to
> wallow in. I don't like the smell of damp and draughts.
... all of which is easily achievable in either an old house or a new
build.
> Frankly, most of the stock of house built between 1880 and 1950 could
> probably be better torn down, and replaced, if only the developers had
> more than a half pounce of imagination and flair between them. And save
> a huge amount on heating bills.
So you're one of those people who'd rather spend 6 figures per house
rebuilding than 3-4 figures insulating. The crass foolishness of such
a blanket policy has been seen before. There are always some cases
where it makes sense due to other factors, but as a blanket policy its
just foolish and destructive.
And fwiw, the vast majority of developers either don't have
imagination and flair, or more often arent willing to spend the extra
to achieve it. And of course BR and planning heavily restrict attempts
to make houses nicer or better featured. We have to live with the
reality of these issues rather than a dream.
> If I've seen one row of victorian two up
> two downers with a kitchen/bathroom extension on the back, I've seen a
> thousand, If I have seen one street of bow windowed demi-tiled 30's
> houses with single brick construction, and stained glass about the
> doorways and tiled porches I've seen a thousand..
ditto new builds - so what
> Trash em I say. All bar a representative few. Ugly, badly built, near
> the end of their useful lives, and totally useless and energy
> inefficient an unsuited for modern living.
I'd say that viewpoint is well cobbled.
If you look at the market value of old versus new buildings you'll
notice your view is massively outvoted.
> Thst what the Victorians and Edwardians did to all the ramshackle
> country hovels that no doubt you would drool over.
Challenging your illogic doesn't mean I like hovels. Thats just more
illogic.
> Used to be one near
> where I lived, on the fens. No water, no toilet, no electricity, no
> access road, and just about all that was left was a central brick
> chimney, and a collapsing structure of rotten oak beams. Overgrown with
> brambles. Would have cost a fortune to put services into, although the
> location might have made it worth while. That old fen used to have nigh
> on a thousand people living on it, or off it, 100 years ago. five pubs,
> two churches..now its about three farms and about 50 labourers cottages
> lived in by god knows who..
Populations occasionally leave an area, and what remains isnt worth
investing in... I dont know what you think that proves.
> Times change, and housing has to change with it. People are not
> prepared to live the way they lived 100 years ago, and no wonder..and
> the houses designed for that era are not fit for purpose today.
About 20 million Brits live in such old houses, and most of them work
fine. Their market value reflects that fact.
> You may,
> if you are middle class and affluent, take one and spend a lot of money
> making it so, but the original inhabitants couldn't afford to.
Yes, we upgrade houses at times. Showers, internet, insulation...
Just because your old house was a complete mess doesnt mean all others
are.
NT
Tim Lamb
<17b3d599-f083-49de...@y9g2000yqg.googlegroups.com>,
meow...@care2.com writes
>On Apr 20, 12:38 am, The Natural Philosopher <t...@invalid.invalid>
>wrote:
>> meow2...@care2.com wrote:
Massive snip!
>Yes, we upgrade houses at times. Showers, internet, insulation...
>Just because your old house was a complete mess doesnt mean all others
>are.
May I offer to hold your coats:-)
No sooner had the compressor started up to begin removing the concrete
floor in my Victorian barn than the planning enforcement officer was
along to do battle for the nimbies.
In fact he readily agreed that as it is agricultural and not listed
there was no interest from town planning.
However, it is an excellent argument for what you are both saying. A
century or so of alterations as farming needs changed has wrecked what
might have been a sound building. The question now is whether I can
afford to re-work the structure up to modern standards with a realistic
pay back or retain a two storey stable block 10m from my front door.
regards
>
>
>NT
--
Tim Lamb
Stuart Noble
> Another popular myth. Damp doesn't 'get in', the net flow of damp in
> all houses is from interior to exterior. Think about it: we cook, we
> breathe, we shower; if the net flow of damp werent from interior to
> exterior the house would flood.
>
thinking over at Periods.com?
Unless you're running a laundry with the windows closed, the humidity of
a normal house is below the outdoor level. A building centrally heated
to 18 deg C will be short of moisture during the winter. If you've ever
worked in a modern office, you'll be familiar with the static build-up
because of low humidity despite all those humans breathing (often heavily).
You still don't seem to have grasped the difference between water and
water vapour. Materials that stop rain pouring in don't necessarily
prevent vapour getting out.
meow...@care2.com
> > Another popular myth. Damp doesn't 'get in', the net flow of damp in
> > all houses is from interior to exterior. Think about it: we cook, we
> > breathe, we shower; if the net flow of damp werent from interior to
> > exterior the house would flood.
> >
> No such thing as penetrating damp then. Is that part of the new wave
> thinking over at Periods.com?
Even in those cases, the net flow of water vapour must still be from
interior to exterior, it it werent the house would flood. Do you
understand why?
> Unless you're running a laundry with the windows closed, the humidity of
> a normal house is below the outdoor level.
If you mean lower RH, yes. If you mean weight of water vapour per
cubic metre of air, its higher. Interior/exterior air exchange is an
important mechanism for getting rid of interior vapour, even in a cold
wet winter. Air holds much more water vapour as temp increases, and RH
is a measure of the level of saturation, not of grams per cubic metre.
If you take damp cold outdoor air and warm it to 20C, RH drops and it
feels dry.
> A building centrally heated
> to 18 deg C will be short of moisture during the winter. If you've ever
> worked in a modern office, you'll be familiar with the static build-up
> because of low humidity despite all those humans breathing (often heavily).
Right. Your point is?
> You still don't seem to have grasped the difference between water and
> water vapour.
strange thing to say
> Materials that stop rain pouring in don't necessarily
> prevent vapour getting out.
Indeed, but some do, and some have caused many a problem.
NT
The Natural Philosopher
he really doesn't understand damp at all.
By his reckoning, we would be wetter inside a house than standing
outside in the rain..
All house needs even by today's ridiculous standards is a 4" hole in the
wall for every room, to completely ventilate it. It doesn't need to be
permeable at all. And indeed, if its insulated with celotex, there is no
way its going to be permeable.
Impermeable sheathing is fine as long as water ingress behind it does
not happen.
What's generated within the house is easily coped with by modest
ventilation, and use of a vapour barrier between the inside and the
outer walls, to prevent condensation.
He has picked up ion te ione issue..where water iunfgress is happing
elsewher -0- either risng damp or leakling roofs, and is misdiagnised as
penetrating rain. There adding a waterprrof covering willlead to a
massive acceleration of rot.
Of course, since the reason the rendering was applied is usually signs
of rot and damp, its a moot point as to whether this makes things worse,
or merely disguises the process for long enough to sell it to an
suspecting twat ...
I've used waterproofing on my rendering where water splash (off drip
boards and a piece of slate left too near the house!!) and a north
aspect was giving me frost damage. Its completely cured it.
meow...@care2.com
> Stuart Noble wrote:
> >
> >> Another popular myth. Damp doesn't 'get in', the net flow of damp in
> >> all houses is from interior to exterior. Think about it: we cook, we
> >> breathe, we shower; if the net flow of damp werent from interior to
> >> exterior the house would flood.
> >>
> > No such thing as penetrating damp then. Is that part of the new wave
> > thinking over at Periods.com?
> >
> > Unless you're running a laundry with the windows closed, the humidity of
> > a normal house is below the outdoor level. A building centrally heated
> > to 18 deg C will be short of moisture during the winter. If you've ever
> > worked in a modern office, you'll be familiar with the static build-up
> > because of low humidity despite all those humans breathing (often heavily).
> >
> > You still don't seem to have grasped the difference between water and
> > water vapour. Materials that stop rain pouring in don't necessarily
> > prevent vapour getting out.
>
> he really doesn't understand damp at all.
>
> By his reckoning, we would be wetter inside a house than standing
> outside in the rain..
I didnt realise youd grasped that little.
NT
Stuart Noble
> Stuart Noble wrote:
>>> Another popular myth. Damp doesn't 'get in', the net flow of damp in
>>> all houses is from interior to exterior. Think about it: we cook, we
>>> breathe, we shower; if the net flow of damp werent from interior to
>>> exterior the house would flood.
>>>
>> No such thing as penetrating damp then. Is that part of the new wave
>> thinking over at Periods.com?
>
> Even in those cases, the net flow of water vapour must still be from
> interior to exterior, it it werent the house would flood. Do you
> understand why?
No, and I don't see how it's relevant. What we are concerned with is
water pissing through the walls, not relatively small amounts of vapour
going in or out.
>
>
>> Unless you're running a laundry with the windows closed, the humidity of
>> a normal house is below the outdoor level.
>
> If you mean lower RH, yes. If you mean weight of water vapour per
> cubic metre of air, its higher. Interior/exterior air exchange is an
> important mechanism for getting rid of interior vapour, even in a cold
> wet winter. Air holds much more water vapour as temp increases, and RH
> is a measure of the level of saturation, not of grams per cubic metre.
> If you take damp cold outdoor air and warm it to 20C, RH drops and it
> feels dry.
It doesn't matter how much moisture is in the air as long as the air is
warm enough to support it. In a normal house this shouldn't be an issue.
>
>
>> A building centrally heated
>> to 18 deg C will be short of moisture during the winter. If you've ever
>> worked in a modern office, you'll be familiar with the static build-up
>> because of low humidity despite all those humans breathing (often heavily).
>
> Right. Your point is?
I would have thought the point was clear. Moisture generated from the
inside isn't sufficient to satisfy the requirements of warm air in
winter, hence there is no movement of moisture outwards.
>
>
>> You still don't seem to have grasped the difference between water and
>> water vapour.
>
> strange thing to say
>
>
>> Materials that stop rain pouring in don't necessarily
>> prevent vapour getting out.
>
> Indeed, but some do, and some have caused many a problem.
Can you think of a material that vapour doesn't waltz through with ease?
Certainly not anything cement based. Possibly the spray on, never paint
again, acrylic coatings. I've seen examples of water trapped behind
those, but I've also seen them rock solid after 20 years. My hunch is
that they work best when the brickwork was sound and they weren't
required anyway. Even so, the coating has remained intact and the
buildings haven't suffered. In other words they fail because rainwater
gets behind them, not because of the migration of vapour.
Stuart Noble
I really think you need to answer that if you're to have any credibility
meow...@care2.com
Theres no question there... and no real point
NT
meow...@care2.com
> meow...@care2.com wrote:
> > Stuart Noble wrote:
> >>> Another popular myth. Damp doesn't 'get in', the net flow of damp in
> >>> all houses is from interior to exterior. Think about it: we cook, we
> >>> breathe, we shower; if the net flow of damp werent from interior to
> >>> exterior the house would flood.
> >>>
> >> No such thing as penetrating damp then. Is that part of the new wave
> >> thinking over at Periods.com?
> >
> > Even in those cases, the net flow of water vapour must still be from
> > interior to exterior, it it werent the house would flood. Do you
> > understand why?
>
> No, and I don't see how it's relevant.
Its key to understanding how old houses handle damp.
Lets put it another way... imagine we sealed a house up 100% water &
vapour tight. Imagine occupants could continue breathing. Now, they're
breathing out water vapour day & night. In a sealed container that
will condense, run down the walls, and the house would gradually fill
up with water.
The point here is that every house, without exception, necessarily has
a net flow of water vapour from interior to exterior. If it didnt, the
above would happen. Its simply not possible for a habitable building
to have a net flow of water vapour from exterior to interior over any
significant amount of time.
> What we are concerned with is
> water pissing through the walls,
no, we're not. Everything I've said assumes any holes with water
pissing in either dont exist or have been repaired. If you have a hole
like that the rest is moot.
> not relatively small amounts of vapour
> going in or out.
> >
> >
> >> Unless you're running a laundry with the windows closed, the humidity of
> >> a normal house is below the outdoor level.
> >
> > If you mean lower RH, yes. If you mean weight of water vapour per
> > cubic metre of air, its higher. Interior/exterior air exchange is an
> > important mechanism for getting rid of interior vapour, even in a cold
> > wet winter. Air holds much more water vapour as temp increases, and RH
> > is a measure of the level of saturation, not of grams per cubic metre.
> > If you take damp cold outdoor air and warm it to 20C, RH drops and it
> > feels dry.
>
> It doesn't matter how much moisture is in the air as long as the air is
> warm enough to support it.
It does. If RH is 80%, condensation happens, plus it feels
uncomfortable, plus moulds etc proliferate etc.
> In a normal house this shouldn't be an issue.
Obviously. And obviously sometimes it is.
> >> A building centrally heated
> >> to 18 deg C will be short of moisture during the winter. If you've ever
> >> worked in a modern office, you'll be familiar with the static build-up
> >> because of low humidity despite all those humans breathing (often heavily).
> >
> > Right. Your point is?
>
> I would have thought the point was clear. Moisture generated from the
> inside isn't sufficient to satisfy the requirements of warm air in
> winter,
that doesnt make sense. Warm air doesnt require moisture.
> hence there is no movement of moisture outwards.
and thats illogical. Where do you think all that water vapour goes if
not outside? Do you think interior RH increases forever without
problem? Do you think the water vapour somehow ceases to exist? It has
to get outside one way or another, theres simply no other possibility.
> >> You still don't seem to have grasped the difference between water and
> >> water vapour.
> >
> > strange thing to say
> >
> >
> >> Materials that stop rain pouring in don't necessarily
> >> prevent vapour getting out.
> >
> > Indeed, but some do, and some have caused many a problem.
>
> Can you think of a material that vapour doesn't waltz through with ease?
> Certainly not anything cement based. Possibly the spray on, never paint
> again, acrylic coatings. I've seen examples of water trapped behind
> those, but I've also seen them rock solid after 20 years. My hunch is
> that they work best when the brickwork was sound and they weren't
> required anyway. Even so, the coating has remained intact and the
> buildings haven't suffered. In other words they fail because rainwater
> gets behind them, not because of the migration of vapour.
Yes, even painted cement has not enough vapour permeability for some
situations. Cement rendered earth walls are a classic nightmare
combination for exactly this reason.
NT
The Natural Philosopher
>
>
> Its key to understanding how old houses handle damp.
>
> Lets put it another way... imagine we sealed a house up 100% water &
> vapour tight. Imagine occupants could continue breathing. Now, they're
> breathing out water vapour day & night. In a sealed container that
> will condense, run down the walls, and the house would gradually fill
> up with water.
>
> The point here is that every house, without exception, necessarily has
> a net flow of water vapour from interior to exterior. If it didnt, the
> above would happen. Its simply not possible for a habitable building
> to have a net flow of water vapour from exterior to interior over any
> significant amount of time.
>
Thats why you have ventilation, dear lisa.
>
>> What we are concerned with is
>> water pissing through the walls,
>
> no, we're not. Everything I've said assumes any holes with water
> pissing in either dont exist or have been repaired. If you have a hole
> like that the rest is moot.
>
No it isn't, because now we have ventilation, there is no way for water
to get into the structure except via water pissing in.
>> It doesn't matter how much moisture is in the air as long as the air is
>> warm enough to support it.
>
> It does. If RH is 80%, condensation happens,
No, it doesn't. It has to be 100% at the point it occurs. That is the
definition.
> plus it feels
> uncomfortable, plus moulds etc proliferate etc.
>
No, they do not. They need actual wet structures, not just warm wet air.
>> In a normal house this shouldn't be an issue.
>
> Obviously. And obviously sometimes it is.
>
Not if it has adequate heating and ventilation, or adequate insulation
and ventilation and less heating.
>
>>>> A building centrally heated
>>>> to 18 deg C will be short of moisture during the winter. If you've ever
>>>> worked in a modern office, you'll be familiar with the static build-up
>>>> because of low humidity despite all those humans breathing (often heavily).
>>> Right. Your point is?
>> I would have thought the point was clear. Moisture generated from the
>> inside isn't sufficient to satisfy the requirements of warm air in
>> winter,
>
> that doesnt make sense. Warm air doesnt require moisture.
>
Makes perfect sense to me. Ventilation introduces air with a very low
moisture content, even if outside is 70% RH, heating it lowers RH to
maybe less than 15%. It feels dry and needs extra moisture to feel
comfortable. You do that by restricting ventilation to allow a bit of
steaminess to build up.
>
>> hence there is no movement of moisture outwards.
>
> and thats illogical. Where do you think all that water vapour goes if
> not outside? Do you think interior RH increases forever without
> problem? Do you think the water vapour somehow ceases to exist? It has
> to get outside one way or another, theres simply no other possibility.
>
Ventilation dear lisa.
>
>>>> You still don't seem to have grasped the difference between water and
>>>> water vapour.
>>> strange thing to say
>>>
>>>
>>>> Materials that stop rain pouring in don't necessarily
>>>> prevent vapour getting out.
>>> Indeed, but some do, and some have caused many a problem.
>> Can you think of a material that vapour doesn't waltz through with ease?
>> Certainly not anything cement based. Possibly the spray on, never paint
>> again, acrylic coatings. I've seen examples of water trapped behind
>> those, but I've also seen them rock solid after 20 years. My hunch is
>> that they work best when the brickwork was sound and they weren't
>> required anyway. Even so, the coating has remained intact and the
>> buildings haven't suffered. In other words they fail because rainwater
>> gets behind them, not because of the migration of vapour.
>
> Yes, even painted cement has not enough vapour permeability for some
> situations. Cement rendered earth walls are a classic nightmare
> combination for exactly this reason.
>
Not really. The key is that you need ventilation in all structures, and
some heat. That carries way all the moisture. Then you can make the
structure as impermeable as you like: In fact a modern house is gas
tight to an extent. The ultimate aim of insulation in a modern house is
to render it with a very low leakage of both heat and air (draught
suppression) and then strictly control ventilation to the absolute
minimum for sensible air replacements. In a house built to modern
specifications this ventilation is THE dominant heat loss.
And once you do that you need to make the interior walls completely
impermeable with foiled board etc to prevent ANY internal moisture
travelling to the far side of the insulation, where the structure is
cold and therefore condensation possible.
None of the *internal* moisture ever goes NEAR the structure.
Now this is basically what you have to do to get an old house to be
insulated. You have no other option.
What may or may not become a problem then is ingress of external water
into the structure, and failure to remove it from there.
You cvabnt rely on sucking the water into the house and up a chimney,
and you may or may not be able to let it breathe outwards. However, the
key to thi sis simply that it has to get out as afst as it gets in. Then
all is happiness. You do that either by stopping it getting in with
various things like rooves, damp proof courses and damp proof render, or
if these aren't working, or don't exist, you have to let it breathe out.
A classic case is an oak frame on a brick plinth with no DPC. render
that outside, and rising damp simply ends up inside the house an in the
sole plates. You should inject it before rendering it, and then the very
little that dies get in, doesn't travel up the sole plate - it simply
evaporates from the interior to to the underfloor space below the
injection level.
>
> NT
Stuart Noble
> Lets put it another way... imagine we sealed a house up 100% water &
> vapour tight. Imagine occupants could continue breathing. Now, they're
> breathing out water vapour day & night. In a sealed container that
> will condense, run down the walls, and the house would gradually fill
> up with water.
The occupants would presumably be introducing drinking water from
outside, so it would hardly be a sealed container. Otherwise, no
condensation if the air was warm enough
>
> no, we're not. Everything I've said assumes any holes with water
> pissing in either dont exist or have been repaired. If you have a hole
> like that the rest is moot.
You don't need holes in the wall, you just need a 9" brick wall with
what was lime mortar, but is now a crumbling pile of powder. You cannot
repair the mortar in a Victorian house without knocking it down first
> It does. If RH is 80%, condensation happens, plus it feels
> uncomfortable, plus moulds etc proliferate etc.
Not true. We regularly have 80% RH in a hot summer and the clothes on
the washing line dry in an hour. Consider that tropical timber often
dries too quickly in virtually 100% RH conditions if the temperature is
high enough.
> Warm air doesnt require moisture.
Let's just say it will take it from anywhere it can. What happens to
your body in a sauna? Don't answer that.
> Where do you think all that water vapour goes if
> not outside? Do you think interior RH increases forever without
> problem? Do you think the water vapour somehow ceases to exist? It has
> to get outside one way or another, theres simply no other possibility.
If you're generating that much moisture, open the bloody window for
chrissake. Mostly the moisture you breathe in is the same as the
moisture you breathe out. Your body doesn't manufacture it
>
>
> Yes, even painted cement has not enough vapour permeability for some
> situations. Cement rendered earth walls are a classic nightmare
> combination for exactly this reason.
Well, if you're going to live in a mud hut you have to accept the
consequences.