Advice please on roofing

windbound

If I was to have a 80m2 single pitched residential roof with a slope of 6 degrees, with plenty of load bearing support beneath, does anyone think it's possible to have torch on felt covered with concrete tiles without having leakage problems? Thank you

Bonzo Delaney

windbound wrote: »

If I was to have a 80m2 single pitched residential roof with a slope of 6 degrees, with plenty of load bearing support beneath, does anyone think it's possible to have torch on felt covered with concrete tiles without having leakage problems? Thank you

Id look into a warm deck covered in fibreglass then your tiles over that I presume you intend on using paving slabs or similar allow channels for drainage

windbound

Thanks Bonzo I'll look into warm deck but not sure what you mean with the paving slabs, drainage channels.

Bonzo Delaney

windbound wrote: »

Thanks Bonzo I'll look into warm deck but not sure what you mean with the paving slabs, drainage channels.

Do you mean a flat roof you can walk on.

windbound

No, not to walk on. Just a house extension roof. This idea is just one of a few and I'm wondering would it work. We've had a previous extension with a flat roof with felt with a 4 inch drop and had no problems for 30 years. That's why I'm wondering would it be possible to cover a new extension with tiles too. (We have free concrete tiles at our disposal so they won't be an extra cost)

Bonzo Delaney

windbound wrote: »

No, not to walk on. Just a house extension roof. This idea is just one of a few and I'm wondering would it work. We've had a previous extension with a flat roof with felt with a 4 inch drop and had no problems for 30 years. That's why I'm wondering would it be possible to cover a new extension with tiles too. (We have free concrete tiles at our disposal so they won't be an extra cost)

Concrete tiles won't work at 6 degrees the rain will just fall back in over the top of them you would need at least 22 degrees for tiles some newer type go down to 12 degrees I think.

windbound

Thanks Bonzo. You're right. I thought maybe a slightly sagging felt below might take away any leakage. Might have problems
where battens are nailed though. Probably a bad idea. Thanks for the advice.

bertie 56

windbound wrote: »

Thanks Bonzo. You're right. I thought maybe a slightly sagging felt below might take away any leakage. Might have problems
where battens are nailed though. Probably a bad idea. Thanks for the advice.

Well, it's not a bad idea, IMO and it's theoretically possible. The tiles would only be for aesthetical reasons.
I only see two problems, since your tiles will leak : battens that will rot and probably leaks over time where your battens are fixed to the structure ( holes in your torch on felt )
You might get away with the batten problem using some tropical hardwood like ipe for your battens ( but pricey and very hard to nail / screw in . A good start is to see the decking wood ) or aluminum or whichever material that is water resistant .

You might get away with the holes problem putting double sided butyl tape between the felt and the battens .

All this with good sized battens and counter battens to create a good ventilation space, in order to have this dry between the showers !

It will probably last some few years , but surely won't beat a roof where the tiles are waterproof !

( I had the same idea with natural slates, to cover aesthetically a very low pitch roof. Project still at a project state ! )

Tell us if you go for it, and what is the result ( good or bad...)

windbound

Thanks Bertie 56. Sorry for delay. All good advice. Let you know if we go ahead with it. I'm trying to avoid a double pitch with the tiles because of height but we'll see. Thanks again and thanks to Bonzo for advice too. Appreciate it.

tabby aspreme

OP, have you considered tile effect roof cladding, some manufacturers claim it's waterproof down to 4 degrees.

windbound

Thanks Tabby. Yeah looked into cladding. Finding it difficult to get pricing. Definitely a good way to go but as always there's a budget and I still haven't received any quotes so it's difficult to plan.