Flat Roof Leak - Help!

[AdamM2012]

Hello,

I recently moved into a bungalow where I'm having some trouble with a flat roof leak.

When we moved in, there was a hole in the ceiling below, where water had come through previously. When it rained, water was dripping in. We went up on the roof and found that the felt above the hole wasn't in great condition, so we temporarily painted it with that grey sealing paint for roofs. We then had no more water come through.

We then got a roofing company in to replace the felt and plywood underneath. They did this, but only put the felt up as far as where the roof meets the bottom of the tiles (see attached photo). It soon rained and the water came back in. We checked the roof and the felt wasn't very well held down by the tiles (you could get your finger in, in some places).

They then came back and put flashband over the felt. This seemed to solve the problem for a month or so, but then the water returned.

They came back once again for the third time, removed the flashband and put cement there and coated that with weathershield. As soon as it rained again, it came pouring in (even worse than before). We have checked up there again ourselves and the cement looks cracked in some places (and it's only been a week since they came back).

The water seems to be coming in from between the joints of plywood that are underneath the felt.

Having explained all of this to the owner of the company, he says he can't understand how the rain is getting in and that "it must be coming from somewhere else". He is due to come back again, but keeps dragging it out.

My reason for posting here is to ask what people think of the above. I've spoke to people who say that felt should be laid under the first row of tiles, not just to the very bottom of the tiles. I've also heard how cement shouldn't used on flat roofs too.

To complicate things slightly further, the chimney on our bungalow is also leaking, which has made our loft wet in places. I can't see any wet places towards the flat roof, but I don't know if this may be a factor as to why it is leaking in the first place.

What are people's opinions of this work? We want to get the roof fixed but we're quite sceptical that they will ever manage to do it!

I've also attached an estate agent photo of the bungalow. The flat roof in question is the one on the right.

Sorry for such a long post, but I hope someone can help!

Untitled

• AdamM2012
• 2 Feb 2015
• 1

Untitled

• AdamM2012
• 2 Feb 2015
• 1

 

[Alastairreid]

The first row of slates should have been removed and an upstand formed then the slates refitted.

I cant see how they managed to strip and renew the deck without removing at least the bottom row of slates.

Flashband, cement and tar on a new roof is unacceptable.

 

[AdamM2012]

Thanks for the reply.

If they come back and put the felt underneath the first row of tiles, what should they seal it down with to the plywood underneath?

 

[Alastairreid]

The felt should be torched to the roof.

 

[alan333]

They look like Eternit slates, which can be nailed to tile battens like tiles are, rather than straight into the roof boarding like slates are. They also have a rivet to hold the bottom from raising in the wind - they're slid in between the gaps of the row below, and placed through a hole and bent over. Maybe your roofer couldn't figure out how to remove them without breaking them?

 

[Alastairreid]

They dont normally use sarking boards south of the border Alan.

Its a climate thing.

 

[ree]

I suspect that the bay roof and the intersecting pitched roof junction was not properly designed from day one of the build. In essence, the bay deck appears to be too high.
The front elevation design is shocking - check out the abutment and the guttering above it.
Notice how the front door is almost ducking under the gutter.The abutment step flashing is missing? And the deck drops and ponds just where it discharges.

As above, an upstand (150mm?) should be in place, perhaps there is a shallow upstand but we dont have a pic of it?

As above, i think that the roofer panicked when confronting the Eternit, and the lack of an adequate upstand.


When the bottom course of Eternit is removed i should like to see a pic of whats there before FWIW prescribing a remedy.

Worst case scenario for the OP would be a complete bay roof, bottom course and all flashband strip.

OP, did the same roofer work on the chimney stack?

 

[noseall]

The front elevation design is shocking -

It's worse than shocking. Hideous.

There is zero masonry to the right of the bow window. The whole thing looks like it was a later addition and a very poorly designed one at that.

Whilst the height of the door and window is not necessarily out of the ordinary, the main roof eaves at this position was not taken into account.

 

[catlad]

Your better of getting rid of them.