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Extension roof problem: builder gone, no flashing fitted — advice

Joined
29 Jun 2014
Messages
190
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6
Location
Essex
Country
United Kingdom
Afternoon, I had an extension built which started at the end of February 2025, the build should have taken about 8 weeks, but in the end it dragged on for 3.5 months due to delays with materials, etc. The builder was decent in many ways but very disorganised - he always left ordering materials to the last minute, skylight, windows, roofing tiles, one instance is the skylights and double window he priced 3-3.5k, when the window company he uses quoted 6k, he was saying he will have a loss and that’s too expensive so like idiots me and the wife said lets have a look online to see what we can do, 2 weeks of stress to find someone within budget, and then a further delay of a month while they were made. I also started to feel like he might have been slightly out of his depth, but by that point I was already committed, and he had nearly half the budget. The same with roof tiles, flooring, and there were many cases where we had paid the suppliers direct out of the allocated budget.


The roof was a constant issue throughout the build. He complained about the pitch, tiles, the skylight, the architect — always something. Eventually, the build was finished, but when the planning officer came round, they flagged that there’s no flashing between the new roof and the existing house and that he couldn’t sign it off until that was done, but all was needed was he would drive by when I said it has been completed.


Since then, the builder has basically ghosted me — he’s off on another job, not answering calls or texts. I’ve resigned myself to the fact that I either try to sort it myself or bring in someone else, but I’m reluctant because finding reliable tradespeople has always been a struggle for me.


I’m fairly handy with DIY, and from what I’ve seen, step flashing looks like a process I could follow.


Has anyone here tackled step flashing themselves, or is this something I’d be better off biting the bullet and getting a roofer in for?


I do know I have a further problem, which is much bigger but I thought I’d get the planning signed off then look at what I can do with the roof, I did speak with a guy that was fitting some guttering to a neighbours house and he said the builder has had a nightmare and looks to have cut the top roof tiles too short and the rainwater is missing the guttering and pouring underneath/between guttering and the soffit, he did say that the roof will have to be stripped and a tray underneath might be better. but he couldnt give me a price because it needs stripping off to see what he needs to do, builder originally told me he fixed it but hes used the bendable lead flashing to bridge the gap between guttering and roof tile.
the top tiles against the fibre glass roof are not laying flat either.
 

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Unfortunately your building is lacking in skill level. Clearly some flashing should be part of an extension build (unless agreed otherwise), and I agree that he has cut those tiles too short.

Given his lack of skill, and the bodge with the guttering, I would not want him back.

You can either take the loss, or take the original builder to the small claims court, and claim for no flashing, and inadequate workmanship re the roof edge and guttering.

Depending on your skill/confidence level, either hire another roofer to fix it, or attempt the flashing yourself, either with traditional lead or lead substitute. You will find past posts about flashing on the forum, and there will be people that can provide advice here.
 
thanks, yes to be honest I think the same way, the guy that was repairing the neighbours property said about our builder that hes a general builder at best, not a roofer. I dont think i can fix the roof on my own, but the flashing i think i can do.
 
If you're DIY savvy, you should be able to do this yourself.

Scroll down to the YouTube clips, will give you an idea of what's involved.

Flashing clips

Stepped flashing is what should be installed, but I have see numerous installations of just running the grinder above the tile line and using leadmate to seal the lead flashing.
 
If you're DIY savvy, you should be able to do this yourself.

Scroll down to the YouTube clips, will give you an idea of what's involved.

Flashing clips

Stepped flashing is what should be installed, but I have see numerous installations of just running the grinder above the tile line and using leadmate to seal the lead flashing.
thanks, funnily enough it was this guy i was watching on youtube last night thinking thats doable
 
just a quick question, how good is the sticky lead substitute?
I've used the Easy-trim Lead stuff, looks pants compared to lead but much easier to work with and seems very durable.
Use a bitumen primer and give it a good enough lap up the wall and you might get away without a chase.
You have a decent roof overhang, although you might want to chase it in around the stack, which is easy because it's horizontal.
 

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