Leaking garden room from horizontal uPVC cladding

[sofaman]

Hi,

Our back room is leaking again from the horizontal cladding between lower rectangular glazing and upper glazing at the gable end.

Externally it appears built using all uPVC with a tiled roof. Docs suggest a steel frame was used (there is one glazed end, one part glazed and one solid wall):

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• sofaman
• 20 Apr 2012
• 1

Same problem was "fixed" end of last year under warranty (8 years old) by replacing horizontal external strips that are just below the upper glazing. Looked like the sealant was no longer working long most of the length, so the guy stripped it all off, cleaned a resealed.

It still looks good to me - had a good look and pressed on various bits.

The company has gone bust between last Dec and now, so non-insurance based warranty is of no use and will have to a) diagnose the problem myself whilst b) hunting around for a reliable fixer.

Experience has shown hunting for leaks is hard - I think I need to employ two techniques:

i) Get the hosepipe on squirt mode and test the whole structure bit by bit, methodically. We are not in a hosepipe ban area

ii) Given the leak is just below the horizontal transom, it could be from anywhere above this line, including I suppose anywhere back from the gable end

The leak is from the point marked by the arrow. If I can get the cladding above off, then I should be able to see the path of the incoming water much more easily.

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• sofaman
• 20 Apr 2012
• 1

I cannot see how this piece is fixed - both ends are in plaster, but does appear to be attached somehow along its length.

What is the standard way of fixing this piece? If I apply some force with e.g. paint scraper, is it likely to come off without breaking and bend enough to clear the plaster at each end?


I don't really want to start taking off outside pieces of uPVC this time of year...

Any helpful suggestions gratefully received! [/img]

 

[God]

A pic from the outside will be useful, that trim was put on before it was plastered and it looks like a bit of flat board which is probaly glued on but i think you should look outside first, maybe pop the unit out and check the drainage on the triangle unit before you start pulling trim off

 

[sofaman]

A pic from the outside will be useful, that trim was put on before it was plastered and it looks like a bit of flat board which is probaly glued on but i think you should look outside first, maybe pop the unit out and check the drainage on the triangle unit before you start pulling trim off

The trim is under the plaster by about 5mm each end (3m long). Does appear to be glued on (I can stick a knife in from the underside and feel resistance in various places - uneven and what appears to be clear silicone/glue bits comes out). Thin silicone bead on top edge (I presume to stop inside condensation from upper windows dripping down).

On to the outside:

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• sofaman
• 21 Apr 2012
• 1

Red diamond shows approx height of the bottom of the inside trim, i.e. lowest point at which water could get in (about the same as the soffit on the right, below the guttering).

This is a close up - the horizontal piece was refitted in December after the same leak. The sealant looks very sound along the whole length:

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• sofaman
• 21 Apr 2012
• 1

Wife tells me that it does not necessary leak whilst raining, but sometime afterwards. Drenched a couple of panes without problem. Will leave it a while to see if anything soaks through.

It has been dry since December, so I'm wondering whether the previous 'fix' did not fix a leak that requires either heavy or driving rain (must avoid guessing though...)

 

[sofaman]

Right - got the soffit off.

Thanks to a thread on this forum, used a chisel to remove the poly top off the poly top nails. Then a wire cutter to lift out the heads a little more, then mole grips to pull them out (have a nail bar as well, but only cheap version that wouldn't get under the small nail heads).

Used my mobile's camera in video mode with a torch as a boroscope.

Roof seems to consist of tiles, then sheeting, then a gap, then insulation (compressed foam about 2 inches), then I assume the plasterboard on the inside.

Cannot see any moisture in any of this space, nor do the rafters appear damp in any way. So hopefully the core of the roof is fine and the leak is at the gable end somewhere!

The inside cladding is deffo glued on - it looks like to a horizontal wood joist. This looks like it has expanded at the leaking end, may be acting as a sponge (which would explain the delay in water actually coming in the house).

I'll pop up out the upper DGU later - beading is on the outside, so I assume it will be stuck on as well....

 

[sofaman]

DGU looks fine - resting in a uPVC trough with weep holes that work.

Very heavy rain over the last few days, but only a small leak.

Looking back at weather data - there is a correlation between NW winds and more significant leaking - we are on an exposed site, typical winds here from from SSW. More research and more hosing of various bits...

Here's a photo of the verge:

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• sofaman
• 29 Apr 2012
• 1

I'd though previously that the sheeting (looks a little like old asbestos style stuff) and the felt were part of the waterproofing. Apparently not - only the tiles do this - they all look in good nick.

But the verge (which I'd ignored thinking it is on top of the sheet) is cracked all the way up to the ridge.

So I'm wondering if this is letting in driving rain, soaking through the sheet, down the end rafter past the last DGU, and then eventually down inside the house.

There are a couple of small uPVC cladding panels on the outside that I can pull off to take a look at this path

The verge looks in poor condition anyway (to my eyes), so will get a roofer in to take a look at replacing the verge cement.