- Joined
- 29 Jun 2023
- Messages
- 83
- Reaction score
- 2
- Country
We are in the middle of having our slate roof replaced. They have installed a breather membrane and have put 25mm on insulation board in the rafters above our attic bedroom. I asked for 25mm as the rafters are only 75mm deep so would still leave the 50mm for ventilation. However, turns out there are some 30-40mm wooden chunks up each ceiling eave so the insulation board is currently sitting on top of these. This has resulted in the boards sitting much higher than anticipated and having little to no air gap between insulation and membrane and blocking any ventilation up the eaves. This has caused condensation to start to form above the insulation boards. There is currently no tiles above the membrane so would having tiles above stop this condensation or should I ask the roofer to remove the insulation and return the eaves to how they were with proper ventilation as before?