I am DIY installing some pir insulation between and over the rafters in my loft room. For ventilation, I am leaving a 50mm gap between the insulation and the bitumen felt, will be installing eaves vents and have had new ridge tiles installed with a timloc breathable membrane.
Unfortunately, while installing my insulation at the ridge line I've noticed that the felt doesn't seem to have been cut back enough for allowing air to vent out at the ridge. I can push the bitumen back to make a gap though and have stuck a cardboard tube in the gap over the bad weather last few days to see if pushing this back will cause any water to get in but haven't had any leaks so assume it would be safe to cut back.
Can I trim the bitumen felt from the inside here to create a gap between the felt and the ridge board? If so, what tool would be best to use?
Unfortunately, while installing my insulation at the ridge line I've noticed that the felt doesn't seem to have been cut back enough for allowing air to vent out at the ridge. I can push the bitumen back to make a gap though and have stuck a cardboard tube in the gap over the bad weather last few days to see if pushing this back will cause any water to get in but haven't had any leaks so assume it would be safe to cut back.
Can I trim the bitumen felt from the inside here to create a gap between the felt and the ridge board? If so, what tool would be best to use?
