If the old layer of felt roofing is in good enough condition then a liquid system repair can be applied.
How to repair a flat felt roof.
We had a problem with our shed workshop flat felt roof leaking and needed a quick repair.
Using a utility knife make a shallow cut until you can remove material around the spot without damaging the layers underneath it.
Cut around the damaged area until the membrane rests flat.
Permanent flat roof repair this can either be a patch of torched on roofing felt or a layer on top of your existing.
Apply some bitumen adhesive to the exposed surface and fold back the segments.
For most small punctures you can repair your roof simply by forcing sealant into them.
A waste of time if your felt roof has the problem.
As with most temporary flat roof repair work a paint on solution can fix leaks.
Diy temporary flat roof repair for felt roofs this is often a paint on fixfrom a tin like the repair videos at the top.
Cut a piece of new felt to use as a patch big enough to give above a 50mm 2 inch overlap beyond the repaired blister.
Instead of replacing the felt roof we decided to use a product call.
Press down the top layer into the adhesive.
Apply some bitumen adhesive over the repair and beyond to suit the patch and apply it.