guttering angles

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Ian & Hilda Dedic

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Jul 3, 2007, 12:30:14 AM7/3/07
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Hi chaps
does anyone know of a supplier of half round black guttering angles
where the internal angle is about 150 degrees? all the sheds and
builders merchants do is the 135 deg angle stuff, which is too small an
angle to fit for bay windows.

The only thing I've found is an adjustable angle thing at screwfix but
they're £20 each!!!!

Any ideas?

dedics

Andrew Mawson

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Jul 3, 2007, 2:44:04 AM7/3/07
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"Ian & Hilda Dedic" <news....@dedics.co.uk> wrote in message
news:5eu1mmF...@mid.individual.net...

they're Ł20 each!!!!

Any ideas?

dedics

Where I have two buildings meeting at about 200 degrees I sucessfully
mitred two short lengths of gutter, glued them with pvc cement, and
used normal joiners. Was a bit of a fiddle involving the use of a band
saw.

AWEM

Roger

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Jul 3, 2007, 3:33:02 AM7/3/07
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The message <5eu1mmF...@mid.individual.net>
from Ian & Hilda Dedic <news....@dedics.co.uk> contains these words:

> does anyone know of a supplier of half round black guttering angles
> where the internal angle is about 150 degrees? all the sheds and
> builders merchants do is the 135 deg angle stuff, which is too small an
> angle to fit for bay windows.

> The only thing I've found is an adjustable angle thing at screwfix but

> they're Ł20 each!!!!

> Any ideas?

Polypipe do (did anyway) fabricated angles but if you don't like the
Screwfix price you will be appalled by the cost. I have a 3 year old
catalogue and the cost there is Ł22.85 plus vat for half round.

--
Roger Chapman

Stuart Noble

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Jul 3, 2007, 4:10:33 AM7/3/07
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I think three sided bays are 135 degs

The Natural Philosopher

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Jul 3, 2007, 4:16:24 AM7/3/07
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They can be any angle the builder decided to make them between 0 and 180...

Stuart Noble

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Jul 3, 2007, 5:28:10 AM7/3/07
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A 180 bay would be interesting

The Natural Philosopher

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Jul 3, 2007, 6:57:32 AM7/3/07
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*between*

Obviously as the angles *tend to* 0 and 180, the bay shape gets pretty
unrealistic .Nevertheless it is *possibible*

Bob Mannix

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Jul 3, 2007, 7:09:49 AM7/3/07
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"The Natural Philosopher" <a@b.c> wrote in message
news:11834507...@proxy00.news.clara.net...

To be pedantic between 90 and 180 (assuming the centre bay isn't larger than
the opening!). It is generally pleasing for the side bays to separate from
the wall at 45deg (easier to mark out as well), making gutter angles all
135deg. 60deg for the leaving wall might not be unusual (giving 150deg
gutters) aside from the fact you can't get gutters, I suspect! Was it built
originally without gutters perchance?


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)


The Natural Philosopher

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Jul 3, 2007, 7:17:42 AM7/3/07
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Bob Mannix wrote:
> "The Natural Philosopher" <a@b.c> wrote in message
> news:11834507...@proxy00.news.clara.net...
>> Stuart Noble wrote:
>>> Ian & Hilda Dedic wrote:
>>>> Hi chaps
>>>> does anyone know of a supplier of half round black guttering angles
>>>> where the internal angle is about 150 degrees? all the sheds and
>>>> builders merchants do is the 135 deg angle stuff, which is too small an
>>>> angle to fit for bay windows.
>>>>
>>>> The only thing I've found is an adjustable angle thing at screwfix but
>>>> they're £20 each!!!!
>>>>
>>>> Any ideas?
>>>>
>>>> dedics
>>>>
>>>>
>>>>
>>> I think three sided bays are 135 degs
>> They can be any angle the builder decided to make them between 0 and
>> 180...
>
> To be pedantic between 90 and 180 (assuming the centre bay isn't larger than
> the opening!).

I didn't assume that. :-)

> It is generally pleasing for the side bays to separate from
> the wall at 45deg (easier to mark out as well), making gutter angles all
> 135deg. 60deg for the leaving wall might not be unusual (giving 150deg
> gutters) aside from the fact you can't get gutters, I suspect! Was it built
> originally without gutters perchance?
>

Its easy enough to glue tow sections of gutter together with plastic
weld. Its just D-I-Y rather than B-&-Q...

>

Ian & Hilda Dedic

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Jul 3, 2007, 8:04:11 AM7/3/07
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yes, but we've got 5 sided bays, that's why we have a problem.

Ian & Hilda Dedic

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Jul 3, 2007, 8:06:04 AM7/3/07
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I don't know, but these last few days we've certainly needed them.....

dedics

Stuart Noble

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Jul 3, 2007, 9:03:19 AM7/3/07
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And presumably the first section isn't at 90 degs to the wall.

Cicero

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Jul 3, 2007, 9:27:10 AM7/3/07
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On Tue, 03 Jul 2007 13:06:04 +0100, Ian & Hilda Dedic wrote:

> Bob Mannix wrote:
>> "The Natural Philosopher" <a@b.c> wrote in message
>> news:11834507...@proxy00.news.clara.net...
>>> Stuart Noble wrote:
>>>> Ian & Hilda Dedic wrote:
>>>>> Hi chaps
>>>>> does anyone know of a supplier of half round black guttering angles
>>>>> where the internal angle is about 150 degrees? all the sheds and
>>>>> builders merchants do is the 135 deg angle stuff, which is too small
>>>>> an angle to fit for bay windows.
>>>>>
>>>>> The only thing I've found is an adjustable angle thing at screwfix

>>>>> but they're Ł20 each!!!!


>>>>>
>>>>> Any ideas?
>>>>>
>>>>> dedics
>>>>>
>>>>>
>>>>>
>>>> I think three sided bays are 135 degs
>>> They can be any angle the builder decided to make them between 0 and
>>> 180...
>>
>> To be pedantic between 90 and 180 (assuming the centre bay isn't larger
>> than the opening!). It is generally pleasing for the side bays to
>> separate from the wall at 45deg (easier to mark out as well), making
>> gutter angles all 135deg. 60deg for the leaving wall might not be
>> unusual (giving 150deg gutters) aside from the fact you can't get
>> gutters, I suspect! Was it built originally without gutters perchance?
>>
>>
> I don't know, but these last few days we've certainly needed them.....
>
> dedics

==================================
But you might not need it again for another 100 years.

Adding a gutter and downpipe might actually exacerbate the problem since
all the run-off would be concentrated into a 3" downpipe which might
overflow in storm conditions with possible damage to an adjacent wall. The
people who designed your house probably knew that a bay window is best
without a gutter. Save yourself some money and enjoy the stormy weather
when it appears.

Cic.

--
===================================
Using Ubuntu Linux
Windows shown the door
===================================

Ian & Hilda Dedic

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Jul 3, 2007, 12:29:47 PM7/3/07
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correct.

the guttering has always been there but tends to leak at the joins
because of stress because you cant get the angle right with the
prefabricated fixed angles.

dedics

Stuart Noble

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Jul 3, 2007, 1:21:47 PM7/3/07
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Well, I guess you're stuck with the Screwfix option, which has to be
cheaper than having it made, plus you don't need to know the precise angle.
The standard bay is 3 sides of an octagon but I've no idea what the 5
sided is based on. Might be handy to know that if you were getting a quote

Cicero

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Jul 3, 2007, 1:41:45 PM7/3/07
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===================================
My bays are the 5 facet type. The internal angles are about 143
degrees and the bays are about 10 ft wide internally.

Mine has no guttering and to the best of my knowledge there has never
been any. If bespoke guttering is being contemplated it might make sense
to make from wood with a lead lining which are two of the easiest
materials to work.

Stuart Noble

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Jul 4, 2007, 7:31:32 AM7/4/07
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I obviously don't really understand this. If a 3 sided bay is based on
an octagon, 180 - 360/8 =135, the standard gutter angle.
The more sides the polygon has, the less that angle should be, so a 5
section bay should be less than 135 degs, not more. Interesting that a
bay based on 5 sections of a duodecagon looks like it gives an angle of
120, which does seem to be commercially available. OTOH an angle of 150
would be a 6 sided polygon, so couldn't form a bay.
Maybe all this changes if the sections aren't the same size or, more
likely, I'm just no good at geometry. I wonder how you become a chippy
without GCSE maths.

The Natural Philosopher

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Jul 4, 2007, 8:30:49 AM7/4/07
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Stuart Noble wrote:
I wonder how you become a chippy
> without GCSE maths.

You make everything out of regular squares, and 45 degree triangles. And
learn that a 3-4-5 triangles is in fact a right angled one.

And when in doubt, ask the architect.

Bob Mannix

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Jul 4, 2007, 8:55:56 AM7/4/07
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"Stuart Noble" <stuart_no...@ntlworld.com> wrote in message
news:oyLii.9433$nE2....@newsfe3-win.ntli.net...

If a 3 equal-sided bay were half a regular hexagon, the angle the first bay
section left the main wall would be 60deg and the gutter angles 120deg. 3
sided bays are generally flattened half hexagons, where the leaving angle is
45deg,, giving 135deg gutter angles.

For a 5 equal-sided bay, were it half a regular decagon, the leaving angle
would be 72deg, giving 144deg gutter angles (different geometry to 3-sided
bay). This would give an almost semicircular bay. Flattening this to give
(in this case) 150deg gutter angles, would, I guestimate, give a leaving
angle of about 60deg, which probably looks "right" for a 5 sided bay.

I think.

Cicero

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Jul 4, 2007, 9:40:04 AM7/4/07
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><snipped>

==================================
I think you're missing the extra side of a bay which is formed by the
internal width of the bay.

A 5 facet bay actually has *6* sides when you make it a closed figure.
Mine has 4 angles at 143 degrees (approx) and the outer two angles where
the outer edges of the bay join the inside wall are each about 50 degrees.

Five of the sides (forming the outer profile of the bay) are 2' wide and
the 6th side (internal width of the bay) is about 10' wide.

Based on the formula 2n - 4 right angles ( where 'n' is the number of
sides) for the total degrees in a polygon the total should be 720 degrees
in my bay but my measurements are obviously not very accurate as the
measurements produce a total of 672 degrees. If I took the trouble to
measure everything precisely the total degrees would be 720.

Ian & Hilda Dedic

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Jul 4, 2007, 10:19:47 AM7/4/07
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Interesting geometry stuff, I was really just wondering why there were
no cheap mass manufactured guttering angles other than 90 and 135
available, I know mine is not the only house in the world with 5 segment
bays and I've seen houses with more, why should I have to pay 12 times
as much, especially as I need more angles pieces as well....

OR why not make flexible gutterring out of ridged (concertina-ed (is
that a real word?) lightweight section) like airducting stuff .

ho hum...

dedics


Cicero

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Jul 4, 2007, 12:48:22 PM7/4/07
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===================================
I think guttering on bays is really quite rare and almost certainly
unnecessary. Bays can be made to almost any shape (with totally
unpredictable angles) so it would be almost impossible to make a range of
gutter angles to suit all the whims of individual builders. In your
situation I would be inclined to remove the gutter (if present and
defective) and see how well you get on without it.

Of course if you really must have a gutter then DIY is the best bet.
Creating the correct angles from plastic / cement has already been
suggested but gutters can be made from different materials such as wood /
lead, copper, aluminium etc. Personally, I wouldn't bother unless you
have a particularly big bay with frequent heavy run-off.

Stuart Noble

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Jul 4, 2007, 1:37:09 PM7/4/07
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Ian & Hilda Dedic wrote:

> Interesting geometry stuff, I was really just wondering why there were
> no cheap mass manufactured guttering angles other than 90 and 135
> available,

120 is also available, but why I don't know. Even if you make a lead
lined gutter from wood, you're going to need the exact angles

I know mine is not the only house in the world with 5 segment
> bays and I've seen houses with more, why should I have to pay 12 times
> as much, especially as I need more angles pieces as well....
>
> OR why not make flexible gutterring out of ridged (concertina-ed (is
> that a real word?) lightweight section) like airducting stuff .
>
> ho hum...
>
> dedics
>
>

Might be worth getting a quote. IME firms that do guttering and soffits
etc aren't that expensive, and at least you'd find out how possible it is.

Stuart Noble

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Jul 4, 2007, 2:29:50 PM7/4/07
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which might explain the availability (albeit scarce) of 120 angles.

>3 sided bays are generally flattened half hexagons, where the leaving angle is
> 45deg,, giving 135deg gutter angles.


> For a 5 equal-sided bay, were it half a regular decagon, the leaving angle
> would be 72deg, giving 144deg gutter angles (different geometry to 3-sided
> bay). This would give an almost semicircular bay. Flattening this to give
> (in this case) 150deg gutter angles, would, I guestimate, give a leaving
> angle of about 60deg, which probably looks "right" for a 5 sided bay.
>
> I think.

I find it easier to visualise the whole polygon so that 3 sides of 8
gives you 135 degs, 3 sides of 6 gives 120 and, as you say, half a 10
sided polygon produces an angle of 144. The OP's estimate of 150 degs
would equate to half a 12 sided i.e. a 6 section bay.
I think...


Stuart Noble

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Jul 4, 2007, 2:31:52 PM7/4/07
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I think the extra side is a red herring though my brain isn't
functioning well enough to be sure.

Cicero

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Jul 4, 2007, 3:22:34 PM7/4/07
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>> -------------------------------


>>
> I think the extra side is a red herring though my brain isn't functioning
> well enough to be sure.

==================================
I think that you're assuming sections of regular polygons - equal sides /
equal angles. This isn't usually the case with window bays.

Bob Mannix

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Jul 5, 2007, 3:09:05 AM7/5/07
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"Stuart Noble" <stuart_no...@ntlworld.com> wrote in message
news:yGRii.22948$ri2....@newsfe5-win.ntli.net...
Yesbut, you are (perhaps?) missing the point that, for aesthetic reasons,
it's not half of a regular polygon. The half polygon is squished up against
the house so it ceases to be regular. All one is left with then is (for a
odd number of sections, 3,5 whatever), the facts that: the central section
is parallel to the opening and the sections are equal width. From this,
using geometry you can work out the gutter angles once you have
chosen/measured the angle the first section on either side leaves the house
wall at (what I call the leaving angle).

As it happens I have a 5 bay window that I measured last night. The gutter
angle for mine is about 155degrees with a leaving angle of roughly
55degrees. My bay covers two floors and the rendered bit between windows is
a smooth curve, finishing with lead flashing above the downstairs window
turned up to form a small gutter so run-off is off either side.

As to the OP, he might be better to do without, add lead flashing to move
drips away from the window or have a bespoke section made (look for people
who do zinc or lead roof work.

Ian & Hilda Dedic

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Jul 5, 2007, 5:18:36 AM7/5/07
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It's not just the run off from the bay I'm worried about, it's all the
water from the front of the main roof, which in the last few days has
been pretty spectacular!

Anyway lots of suggestions there, thank you everyone, --- I'm off to
buy some pvc cement and a hacksaw....

dedics

The Natural Philosopher

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Jul 5, 2007, 5:45:14 AM7/5/07
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You may need to 'lap' another piece of guttering oner the join for best
strength..put a small section in the oven until it goes soft..think its
about 100C or so - and use gloves to 'form' it round the glued together
sections, and then glue it on.

A butt joint is never that good, but with a lapped joint it is EXTREMELY
strong.


>
> dedics

Ian & Hilda Dedic

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Jul 5, 2007, 6:27:44 AM7/5/07
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lots of previous posts clipped:.>>>

>>
>> It's not just the run off from the bay I'm worried about, it's all the
>> water from the front of the main roof, which in the last few days has
>> been pretty spectacular!
>>
>> Anyway lots of suggestions there, thank you everyone, --- I'm off to
>> buy some pvc cement and a hacksaw....
>
> You may need to 'lap' another piece of guttering oner the join for best
> strength..put a small section in the oven until it goes soft..think its
> about 100C or so - and use gloves to 'form' it round the glued together
> sections, and then glue it on.
>
> A butt joint is never that good, but with a lapped joint it is EXTREMELY
> strong.
>

Thanks for that tip I was thinking along those lines anyway.

dedics

Cicero

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Jul 5, 2007, 6:50:11 AM7/5/07
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===================================
Is there no gutter on the front of the main roof, or is it blocked up? It
would be worth checking before you start work on the bay.

Ian & Hilda Dedic

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Jul 5, 2007, 9:56:59 AM7/5/07
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Its all part of the same gutter, our bay has a flat leaded bit that
sticks out from the from of the house and its guttering is just part of
the main front of house gutter.

In my travels today I've seen many houses of similar design (1930's
semi) some have gable rooves over the bay but many do not.

All the flat leaded roofed bays seem to have guttering on them.

My guttering is actually working ok now, but tends to drip at the joints
because of the added stress of the angles not really being the right
ones for the angles of the bay, which pushes things out of shape
especially when filled with heavy water load. Also now I've noticed
they're not right, it bugs me....

dedics

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