Has our roof been constructed incorrectly?

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bob10
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Has our roof been constructed incorrectly?

Post by bob10 »

We've had our roof replaced and are having problems with it leaking.

There's currently a leak next to where our house joins our neighbour's house (we are mid-terrace).

The builders are saying that the leak is coming from our neighbour's side,
that the valley (gutter) between the roofs need re-pointing on the neighbour's side.
They want to contact our neighbour to get them to pay to have this valley re-pointed.
This is after having already re-pointed (again) our side of the valley, which is what they originally thought was the problem.
Our neighbour has no leaks on their side, and will have no reason to want to pay for this.

We feel that any leak on the neighbours roof should not be affecting our roof.
That a leak from our neighbours side, should reach the valley between our roofs and not be able to then get over onto our side.
We think that our roof may have been constructed incorrectly if leak's from our neighbour's side are crossing over onto our roof in this way.

Apparently our roof and our neighbour's were re-roofed together sometime in the 80's.
The valley was left over from this. Our builders didn't replace the valley as they said it didn't need replacing. I
'm not sure why there was a valley anyway, as both roofs had the same tiles running across them, so there wasn't really a need for a valley.
Anyway apparently the felt from when both roofs were re-roofed in the 80's ran over both roofs, under the valley.
When our builders re-roofed recently they just cut this felt off on our side.
It seems to me that they shouldn't have just cut off the felt, as obviously any leaks from the neighbours side will run down the felt,
and if it doesn't find a hole in the felt, the water will end up on our side, under the valley.
It seems like the felt should come from the neighbour's side and over the valley, not under it.

Can anyone tell me how our roof should have been constructed where it meets our neighbour's roof?

Our roof is now slate, whereas our neighbour's still has concrete tiles from the 80's.

Many Thanks for any help.
stuart45
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Post by stuart45 »

Can you put a photo on please?
bob10
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Post by bob10 »

Hi,
what do you want to see a photo of?
If you want a photo of the roof & valley, I can't do that as it's 4 storeys up!
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Post by Geewizz »

This might not be of much use but at least it might give us some clue about the layout. Can you link to your house on google earth or google maps?
Phil
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bob10
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Post by bob10 »

Hi,

I had a look on google maps, and it doesn't zoom in enough to be any use.

I can try and describe anything further. Let me know what's unclear.

Cheers
Geewizz
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Post by Geewizz »

Maybe you could draw a couple of diagrams?
Phil
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bob10
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Post by bob10 »

I will have a go at making some diagrams. I haven't been up there myself, and am only going on the roofer's description of what's up there.

In the meantime, can anyone tell me how a terraced roof should be constructed where slate meets concrete tiles?

Should the felt be under the valley on both sides?
Or should the felt go into the valley, so that any water that does happen to get through the tiles/slates is then fed into the valley rather than under it?

Otherwise I don't quite understand what the valley is for.

Thanks
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thescruff
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Post by thescruff »

Replacing the tiles with slates was rather silly in my opinion, especially as the neighbours are tiles as well.

You have a pad felt under the lead in the valley, and the roofing felt goes into the valley, with the slates on top of that.

One always starts at the bottom with the next level covering the last etc.

2nd slate covers the 1st, the 3rd slate covers the 2nd and part of the 1st, the 4th covers the 3rd and part of the 2nd, so the top of each slate is covered twice.

The edge of the lead in the valley is folded to form a U to prevent any run-off, and again from the bottom up.

Where the slates meet the tiles you would need to make a lead soaker as a transitional piece.

Without photo's it's virtually impossible to give advice.

One comment if the roof has been done properly it wouldn't leak even without the pointing, The problem is 100% down to the roofers work.
bob10
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Post by bob10 »

thescruff wrote: One comment if the roof has been done properly it wouldn't leak even without the pointing, The problem is 100% down to the roofers work.
Hi, this is exactly what I thought, so thanks for confirming.

The roofers are coming round later this week, so we will get them to draw diagrams of what they've done.

The roof would originally have been slate.
The concrete tiles on the neighbours and our roof were put there in the 80's.

Thanks
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thescruff
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Post by thescruff »

Photo's would be better.

I appreciate the roof would have been slate, but it was re-covered along with the neighbours with tiles, you therefor need special lead soakers made up between the two materials.
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Post by thescruff »

There's quite a few videos in the library above about roofing and leadwork, made by JustLead, have a look through a few of them, it may give you a better idea how things go together. here's one to start you off.

<embed src="http://www.ultimatehandyman.org/flvplayer.swf" quality="high" width="450" height="367" name="VideoPlayer" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/go/getflashplayer" flashvars="file=http://www.ultimatehandyman.org/uploads ... r=0xFFFFFF" wmode="transparent" border="0"></embed>
bob10
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Post by bob10 »

Great videos, but none of them show what happens where slate meets concrete tiles.
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thescruff
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Post by thescruff »

Where the two meet the lead soakers you saw in the vid, that was under each slate bends over the top of each tile.

The other method was to form a gutter down the roof, the tiles finish one side and the slates the other.

We need to see what they have done. after that the solution is easy.
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