Jit83

I know, that’s what’s concerning me too. They’re meant to be a reputable company so it’s really frustrating. They have finally agreed to do the job properly after a lot of going back and forth. Thanks for the help on this.

Unfortunately the builder isn’t willing to make any changes to the top side of the roof. They’ve carried out a condensation risk analysis which is attached below. I’ve never seen one of these before but I think it looks OK? 1-MP-240513-101423-147.pdf

Architects drawings:

The architects plans shows 150mm insulation which they have not followed. They’ve agreed the human error on their side. I’ve been paying weekly as they’ve progressed with the project. Won’t be making any more payments until this is resolved. Would a condensation risk analysis be the way forward (with the 50mm insulation against the boards)?

Hi, My builder has only installed 100mm of insulation on the warm flat roof of my extension. The top side is finished and watertight but the plaster needs to be completed on the underside. After I spotted this by shear chance, they said they’ll install a further 50mm underneath between the roof trusses, pushed right against the board. They said the building inspector had suggested this. I’ve called the building inspector who’s now changed his story and said the builder needs to contact the insulation manufacturer. I’ve read reports that the above could cause risk of condensation and damp over the long term. Other than ripping it out and starting again, are there any other options? Can another 50mm be added on top of the waterproof membrane, and then another membrane installed on top? Another thing the builder has said is they can install plasterboard with a membrane on the inside which would act as the vapour barrier. But I will be having spotlights so not sure if this is a valid solution. Any advice would be much appreciated.