Repairing leaking flat roof

[torqueofthedevil]

Hopefully somebody will be able to give me some advice although i admit at the moment the details may be a bit vague.

My mate's roof has started leaking. The roof has never leaked before in about 10 years of living there. I think the house was probably built in about the 1970's.

It is a flat roof and at a guess I'd say the roof area was about 90 m2. I don't know what the roof covering is but would imagine it would be felt? (it may actually be a blue / grey smooth covering - but pretty sure not a rubber covering or lead).

Anyway - she has been quoted by a builder (who hasnt even seen it) £3000 to fix. I've had a quick look and DIY repairing seems easy enough!

Does anyone have any advice?

Main things i wanted to know, other than general pointers are:

1. Considering it has not leaked before wouldnt a small localised repair probably be the most likely and best course of action now?
2. If the damage is a bit more extensive is it best to go to an EPDM roof?
3. Can an EPDM roof be laid directly over the felt roof?

I'd love to be able to help out and do it myself if possible.

[herbialfa]

Are you trying to get into her knickers?????

At this time of year I would patch up where possible.

Then when the weather breaks next year do the whole roof in one go!

Sounds like its just a local failing of the felt!

Best of luck with the roof!

Oh & her knickers!

[Pot Bellied Fool]

I've successfully used roof repair gunk on a bathroom flat roof at my Mum's. Kept it going a few years longer, in the end that was still ok but there were cracks in the felting in other places so got the whole lot done.

I'd be inclined to use that and see how you go - could last a long time but sooner or later, you'll need to get the whole lot done. Find a small outfit - I got a roofing contractor to remove the very old felt, replace the damp bit of board and refelt it all properly. It was in the hundreds rather than thousands and is still fine a good few years on.

[Herbs]

Are you sure you got the size right as 90m2 is massive!

£3000 for a roof that size is pretty reasonable if replacing the boards underneath.

[.:ian:.]

We had an old felt roof replaced with edpm, about 9x4m or so and that cost £2500 + about £200 to add a layer of ply over the pine boards. Involved removing a load of shingle, all the felt, some surrounding roof tiles, adding a layer of ply to make the surface totally flat, laying the edpm.
Quotes for felt were slightly lower, though not much, though the edpm has an underwritten 20yr guarantee.

If its obvious where the water is getting in then try some felt patches and felt adhesive, but we found its v difficult to trace the leak as the water doesnt always follow a straight path..

[andy43]

.:ian:. said:

we found its v difficult to trace the leak as the water doesnt always follow a straight path..

Easier, unless you're really lucky (with the roof, not the knickers), just to replace the lot and be done with it.

[R60EST]

grp (fibreglass) would be a better job , more and more companies doing it now

Edited by R60EST on Tuesday 14th September 22:34

[eps]

Just because the leak is apparent now, it does not mean that water ingress hasn't been happening for quite a while. The main issue is knowing how much has been damaged and therefore how much needs to be replaced.

Electrics? (shudder!)

Joists + Rafters?

Plasterboard?

Timber decking?

Insulation?

Vapour Control Layer?

Waterproof membrane?

Probably the lot if it's getting in, of course it depends on the extent of the damage to the above..

Ideally a little investigative work first would help...

What has the builder actually quoted for, all or part of the above?

[mrmaggit]

Go with what Ian and eps have said, although the best solution is replace with a pitched roof.

[Ej74]

Just had my flat roof done (7m x 4m)

It has been repaired several times but has started to fail in several places

Price paid was 860 (incl. VAT) for 3 layer flat roof and lead work, boards were charged at 30 per a baord needed around 6. total cost just over 1k.

I good price and work was top notch considering over quotes varied from 2.5k to 3.5k

[Mr GrimNasty]

As mentioned, check/repair structure for water damage, then EPDM it. Why anyone would mess about with felt or fibreglass - baffles me.

[blackcab]

Flat roofs fail at the details mainly, failing laps and splits can be repaired really cheaply and easily .. do not try and do a full job yourself.

Felt roofs are strongest by far and will cost anything from £30 to £80 per meter to complete.

if you want me to have a look at it drop me a line

[Flintstone]

Felt roofs don't last forever. Ten years (plus) isn't a bad age. The reason the source of the leak is so hard to trace is that with multi-layers the joins are offset. I've seen water drip through ceilings in the front, right hand corner of a room when the rain was penetrating on the rear, left hand side of the roof. It'll seep and flow between the layers until it eventually finds a way out.

Also, if it's soaked and you patch it up the boards may rot. Best get it done properly, flat roofs are a consumable item.

[ADP68]

My flat, felt garage roof has started leaking onto my cars! I live in South bucks, near High Wycombe and hope to move in the next 2 years. Can anyone recommend to me a roofer near me and also the cheapest route to go down (felt vs rubber) considering I am planning ot move in a couple of years? The roof is at least 10 years old (probably 15) and is blistering in places as well as leaking.
Thanks
Andy

[redeye]

adp68 avienmore roofing is down your way v good company,they are firestone rubber roof merchants
we use them and rubber roof all the time
the best you can get

[ADP68]

Thanks. I've tried googling them, but no joy. Do you have contact details pls?
Andy