Ask your local building control office who will give their advice free.

--

When I had an extension done I thing the pitch was 22.5 degrees. Done
to fit under an upstairs window. Try ringing local building control
tend to be very helpfull. Will probably also depend on the tiles.

On Wed, 10 Sep 2003 13:32:32 +0000 (UTC), "Trevor Smith"
wrote:

Could anyone tell me the minimum angle for a pitched, slated roof. We have
a flat felted kitchen roof at present and I'd like to change it to a
pitched, lean-to, type roof for better looks and relaibility. Also, does
location matter - we're in a seaside town on Cornwall where you tend to get
horizontal rain!



Lawrence

usenet at lklyne dt co dt uk

On Wed, 10 Sep 2003 14:45:02 +0100, Lawrence
wrote:

When I had an extension done I thing the pitch was 22.5 degrees. Done
to fit under an upstairs window. Try ringing local building control
tend to be very helpfull. Will probably also depend on the tiles.

On Wed, 10 Sep 2003 13:32:32 +0000 (UTC), "Trevor Smith"
wrote:

Could anyone tell me the minimum angle for a pitched, slated roof. We have
a flat felted kitchen roof at present and I'd like to change it to a
pitched, lean-to, type roof for better looks and relaibility. Also, does
location matter - we're in a seaside town on Cornwall where you tend to get
horizontal rain!

It depends on the roofing material. My kitchen extension has a pitch
of 17.5 degrees, and it had to have special roof tiles that worked at
that pitch (which had a minimum useable pitch of 17.5). The tiles had
to be laid with a certain overlap, and the architect was so paranoid
about the angle that he specced trussed rafters, much to the builder's
annoyance.

Suggest you find a suppplier of slate tiles and ask them about pitch.

---
Regards,

Colin Swan

In article , Trevor Smith wrote:
Could anyone tell me the minimum angle for a pitched, slated roof.

If slate type interlocking tiles are acceptable you can get down to 15 degrees with Redland Cambrian
http://www.lafarge-roofing.co.uk/cgi..._cambrian_3 0

or

http://www.lafarge-roofing.co.uk then follow the trail

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser http://www.sda.co.uk/qsedbuk.htm

Could anyone tell me the minimum angle for a pitched, slated roof.

I've heard it can be done down to 18 degrees without it getting too
complicated, but much further takes some doing.

Christian.

Trevor Smith wrote:

Could anyone tell me the minimum angle for a pitched, slated roof. We have
a flat felted kitchen roof at present and I'd like to change it to a
pitched, lean-to, type roof for better looks and relaibility. Also, does
location matter - we're in a seaside town on Cornwall where you tend to get
horizontal rain!




It is totally dependent on the tiles or slates used. I had one - still
got teh tiles if you want - horrid things - at about 20 degrees - wasn't
bad till the valleys strated leaking. So I knocked the house down and
built a new one.

Normal tiles 42 degrees is roughly it, but builders like 45 cos it

makes the maths doable by a gibbon with a CSE in Graffiti.


Thatch is 50 minimum.

"Trevor Smith" wrote in message
...
Could anyone tell me the minimum angle for a pitched, slated roof. We
have
a flat felted kitchen roof at present and I'd like to change it to a
pitched, lean-to, type roof for better looks and relaibility. Also, does
location matter - we're in a seaside town on Cornwall where you tend to
get
horizontal rain!


The pitch depends on the tiles or slate you are going to use ..if you look
at the web site of whoever's tiles you want to use, the tech sheet will
state the minimum pitch.

There is typical no max pitch as you can carry out vertical tiling.
Rick

Not quite what the OP asked but...
My low pitched corrugated asbestos garage roof drips condensation from
the underside in cold damp conditions.
What pitch does the roof need to be to cause the condensation to run down
rather
than drip off?

Roger

"Trevor Smith" wrote in message
...
Could anyone tell me the minimum angle for a pitched, slated roof. We
have
a flat felted kitchen roof at present and I'd like to change it to a
pitched, lean-to, type roof for better looks and relaibility. Also, does
location matter - we're in a seaside town on Cornwall where you tend to
get
horizontal rain!

I built an extension where the roof had to have a very shallow pitch - about
10 degrees. It was slated, but under the slates was felt laid in the normal
way. On top of the felt were vertical laths with horizontal laths nailed
across to take the slates. This way no nails went through the felt and the
thing has been perfect so far (10 years).

Rob Graham

Bluestars wrote:

Not quite what the OP asked but...
My low pitched corrugated asbestos garage roof drips condensation from
the underside in cold damp conditions.
What pitch does the roof need to be to cause the condensation to run down
rather
than drip off?


Now there is a curious question.

With MANY variables, like teh surface tension ofteh water, and teh
stickiniess of the roof interiors, its roughness and so on.

In short, it depends on too many variables to give any answer other than
a really rough one.



Roger

robgraham wrote:

"Trevor Smith" wrote in message
...

Could anyone tell me the minimum angle for a pitched, slated roof. We

have

a flat felted kitchen roof at present and I'd like to change it to a
pitched, lean-to, type roof for better looks and relaibility. Also, does
location matter - we're in a seaside town on Cornwall where you tend to

get

horizontal rain!


I built an extension where the roof had to have a very shallow pitch - about
10 degrees. It was slated, but under the slates was felt laid in the normal
way. On top of the felt were vertical laths with horizontal laths nailed
across to take the slates. This way no nails went through the felt and the
thing has been perfect so far (10 years).

Rob Graham




However the felt is not supposed to stop water, but airflow. Its NOT a
good idea to have sagging felt with puddles forming in it around your
timber battens. Mind you, as a bodge, its a good one.

You can use slates on a low pitched roof but you need to overlap more. I
suppose the true answer is something to do with the maximum height water
can be driven up a slope for a given airflow. Machine tiles fit very
accurtely, so aiflow through the gaps is very restricted, hence they
water dosn't drive up very far.

Slates are a lot worse, and don't have interlocking ridges, but my guess
is that 30 degrees is probably (near) the limit unless you go for BIG
overlaps.

Peg tiles - especially hand made - are the worst as they are irregular
with large gaps.

"Bluestars" wrote in message ...
Not quite what the OP asked but...
My low pitched corrugated asbestos garage roof drips condensation from
the underside in cold damp conditions.
What pitch does the roof need to be to cause the condensation to run down
rather
than drip off?

That's surely going to depend hugely on the nature of the surface
which the condensation is running down... I would imagine a completely
smooth surface like glass would allow drops to run at a much shallower
angle than say, rough sawn timber, where there will be a tendency for
drops to propagate at a high point like a splinter, and fall off. I
expect it might make a difference whether the surface is absorbent or
not?

David

IIRC, Redland (now LaFarge) do a tile down to 12 degrees. I think it
is the "Regent" interlocking concrete tile.

Manufacturers specify the minimum angle, but with proper precautions
in terms of lap, fixing and underfelt, then you can go down a few
degrees more.

dg




"Trevor Smith" wrote in message ...
Could anyone tell me the minimum angle for a pitched, slated roof. We have
a flat felted kitchen roof at present and I'd like to change it to a
pitched, lean-to, type roof for better looks and relaibility. Also, does
location matter - we're in a seaside town on Cornwall where you tend to get
horizontal rain!

In article , The Natural Philosopher wrote:
However the felt is not supposed to stop water, but airflow. Its
NOT a good idea to have sagging felt with puddles forming in it
around your timber battens.

That's what the counter battens are for. We used to allow low
pitched roofs built like this, but only with ply over the rafters
to support the felt

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser
http://www.sda.co.uk/qsedbuk.htm

In message , writes
In uk.d-i-y, Paul Mc Cann wrote:

I had to do a quick bodge on a corrugated iron roofed office in an old
(hay barn) warehouse we acquired. [ ... ]

I got some 50mm flat sheets of polystyrene insulation and held them in
situ with some 4mm stimmer line I had available.

Bzzt. Lose 8 bodgepoints for using materials incompatible with farming
tradition. The *only* structural techniques acceptable for lashing up
*anything* in a haybarn are (a) baler twine - for which strimmer line
is not really an acceptable substitute - and (b) gert big blobs of welding.
I thought we'd established this as an unalterable rule of nature a few
years ago...

Surely it would be possible to bend the rules a bit and thatch the roof
internally (using baling twine to hold it in place of course)
--
geoff