Advice On Conservatory Flashing Repair ? (Pic's on profile)

[Steaminboot]

I have a three year old Victorian style, South West facing, conservatory with a leak problem where it abutts to the building. Pictures uploaded to my profile. .The original builders (now bust) installed the flashing too high so that it does not protrude down onto the perspex roof panel but rests on the pvc spar. About a year ago i got another company (also now bust !)who lifted the existing flashing , removed and replaced silicone sealant between the conservatory and the wall , inserted a lower sheet of lead underneath (though i think this has not been raggled into the wall) which now covers the pvc spar but does not lie on the perspex. They also replaced all the lead sealant. It only tends to leak in heavy rain and driving wind with the water not dripping from the roof line where it abutts the wall inside, but from the lintel above the entrance door from the building . The plasterboard accross that wall is evenly stained which would seem to indicate the problem is with the flashing not between the perspex and the pvc. Looking at the flashing i can see that in some places the sealant has cracked particularly at that tricky joint where the roof peaks and there is a square patch of lead covering the top of the two slopes. I have had a quote from a tradesman to replace the flashing for a few hundred quid but i am wondering whether i shouldn't first buy some lead sealant and try to re seal some of the joints myself before spending that sort of money? If it still leaks i've only spent £20 or so and can then go for a full repair. I am aware that the perspex roof will not bear weight and i will have to get crawling boards and ladders. Can anyone offer their thoughts ?
Any advice welcome. Thanks.

 

[Alastairreid]

I doubt it is the flashing.

Google cavity trays.

http://conservatoryinstaller.wordpr...f-you-don’t-sooner-or-later-it-will-cost-you/
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[Steaminboot]

Thanks Alistair , i have had two widely varying quotes so far with neither mentioning cavity trays , but they replied to my post on the Rated People website and both were plumbers rather than builders. I can see how and why it makes sense to have them fitted. Obviously it will mean additional expense but i can only see the problem recurring otherwise. I have someone from a specialist conservatory repair company visiting this evening so i will see if he mentions cavity trays.

 

[Alastairreid]

Not a job for a plumber because i'm pretty sure it has nothing to do with the lead.
Have you checked the window cill above the conservatory?.

Let us know what the conservatory fella has to say, if he doesnt mention the possibile need for trays i would think twice about using his services.

Good luck.

 

[Steaminboot]

Hi Alastair , i'm pleased to say he seems to know his stuff. Like you he straight away said he wasn't convinced the problem was the flashing. The builders who built the extension made a bad job of the render but the firm who i employed to finish the extension rendered over it again instead of removing and replacing it . ( easiest option for them and now i'm paying for it ) He thinks the flashing may not be raggled in deep enough and that water could be soaking through and down the brick work. Firstly though he wants to just repair the lead sealant in the existing flashing and see what effect , if any, that has when the weather worsens again. He will then come back and look again but thinks the render will have to be replaced and explained the option of also then fitting cavity trays. I feel more comfortable as he doesn't just want to rush in and do work that may not cure the problem. He's going to send me quotes for the various stages . I think i need to get out at least another two people with a similar knowledge to quote though.
Looks like this will cost me more than i was expecting but i need a solution that works not more bodges.

 

[Alastairreid]

Thanks for the update.
To be perfectly honest i really don't think replacing the sealant on the lead apron will make any difference at all. If the water was penetrating through the raggle or under the lead the staining would be showing between the polycarbonate sheets and junction of the internal plasterwork.

The problem you describe suggests the water is is penetrating and running down the cavity and entering the room at the lintel above the door.
That is why i suggested you should check the upstairs window cill.

Coat the wall above the conservatory with thomsons waterseal or suchlike this will help prevent rain driven penetration into the cavity...Never know may save you a small fortune.

 

[Steaminboot]

That's real food for thought. To be fair though, i didn't mention it before, but he did ask about the window and sill above and did look closely at it.

I hadn't thought about painting on water sealant to the render . Certainly an attractive option financially . I could do that myself then wait to see if it makes a difference when the bad weather hits again. Is it a long term fix though ? or just a case of accepting i'd have to re coat it every few years ?

What about the render though ? Doesn't it need to be replaced as they have slapped one coat over another ? Or does that just make it unsightly?
He did say it was possible that water was also soaking down between the two coats of render particularly where it was uneven

Thanks for taking the time to reply . I've been let down badly in the past and knowing the possibilities and options certainly helps

 

[Alastairreid]

I hadn't thought about painting on water sealant to the render . Certainly an attractive option financially . I could do that myself then wait to see if it makes a difference when the bad weather hits again. Is it a long term fix though ? or just a case of accepting i'd have to re coat it every few years ?

The lifespan of the sealant will probably depend on the exposure of the elevation you are treating to the elements, i certainly think it would be worth a try..for the sake of £20 or so.

Rendering on top of render in itself should not create any problems as long as both coats have bonded ie not bose, hollow.

One more thing just to be sure...check your guttering above the conservatory is clear with no leaks, no broken slipped or cracked tiles on roof, the felt beneath your tiles/slates is running into the gutter and intact as any water ingress from roof level can and does get into open cavities at the eaves level.