Pitch roof height issue

Sallycyc

Hello, we are in the process of building an extension, today my builder was telling me that we cannot have a pitch roof, because there isn't enough 'height' for it, the tilt will not be enough for the rain water to run, and we can only have a flat roof (which my husband strongly against!!).

I've got a feeling that the builders are lying to me trying to cut costs??

I can't call the building office for advise until Tuesday now, so I would like to know if anyone have any experiences or advise on this matter, isn't correct that the top of the roof cannot be too closed to second floor windows? What is the minimum height for a pitch roof which is accepted by the building reg?

Many thanks in advance! Sally

Johnandabby

Minimum pitch of standard clay plan tile roofs is 35 degrees, but there are some specific tile products for low pitched roofs that are fine down to 15 degrees. The height of the pitched roof will depend on the size of the extension, so you should be able to use simple trigonometry to work this out.


What roof pitch did you have on your drawings?

stef73

What is the angle of the pitch? Might be wrong but mininum for tile is 17 degrees and 25 for slate i only know this as i asked a builder friend about a diy roof on my front bay the other week. You can go less with these http://www.roadstone.ie/products/centurion/

john.h

They may be telling the truth. You need a certain pitch on a roof to use roof tiles. It depends also what type of pitched roof you are having, is it a lean too type? The further your extension goes out, the lower the pitch will be.

John....

Doozergirl

If the pitch isn't steep enough you can have a partially flat roof across the top and then pitch it down at the correct angle. Sort of like this:
__
/ \ instead of /\

Or changing the sides that become the gable ends can mean you have the correct angle.

Or having lower eaves, so a little slope inside the extension.

Or, we have even built a flat roof that conforms to regs and then covered it with a pitch and tiled it. Depending on the design, the price will change.

So far, we've never failed to get a pitch.

Johnandabby

Doozergirl wrote: »

If the pitch isn't steep enough you can have a partially flat roof across the top and then pitch it down at the correct angle. Sort of like this:
__
/ \ instead of /\

Or changing the sides that become the gable ends can mean you have the correct angle.

Or having lower eaves, so a little slope inside the extension.

Or, we have even built a flat roof that conforms to regs and then covered it with a pitch and tiled it. Depending on the design, the price will change.

So far, we've never failed to get a pitch.

Great list of options. Do whatever you can to avoid a flat roof. Lazy approach by the builder IMHO to not explore options nor explain any issue properly.

Obviously does depend on the drawings not showing a roof pitch of less than 15 degrees, but even then the builder should have pointed this out before quoting.

Sallycyc

Johnandabby - do you know what is the minimum degree for a pitch roof which is also comply with building reg? Many thanks!

societys_child

Sallycyc wrote: »

Johnandabby - do you know what is the minimum degree for a pitch roof which is also comply with building reg? Many thanks!

From post #2

Minimum pitch of standard clay plan tile roofs is 35 degrees, but there are some specific tile products for low pitched roofs that are fine down to 15 degrees

jcb208

How far out does the extension come and the height of the wall plate,also bottem of 1st floor window height,Im sure we can work out a near enough pitch

Johnandabby

Sallycyc wrote: »

Johnandabby - do you know what is the minimum degree for a pitch roof which is also comply with building reg? Many thanks!

It's just a case of making sure the tile is suitable for the pitch you have

Sallycyc

Extension is 4.5m out.
Ceiling height 2.3m
Floor to 1st floor window is 3.4m

Yes will probably go for the centurion tile as Stef73 recommended.