A Two-Ply Modified Bitumen Torch Down Rubber Roof will last well over 40 years. There is no other roofing system that can compete with the durability of a two-ply torch down system.
If you happen to have a Modified Bitumen Torch Down roof, and may be in need of repair or is leaking, the best solution would be to fuse another Torch Down Membrane directly over the old one. There are many reasons why a Torch Down Rubber membrane can leak. Some are:
1. The seams were not fused properly
2. The rubber membrane was not protected against Ultraviolet rays – silver paint
3. Poor workmanship
4. No maintenance over the years
Regardless of the condition of the existing torch down roof, fusing a second layer to it will ensure a roof that will last beyond 40 years. Pay attention to the flashing. No matter how well the roof surface is, if the flashing is not done right, your roof will always leak.
Most roof issues stem from flashing. The transition from a rubber membrane to metal flashing is what most roof technicians struggle with.
Warning: If you have a Torch down rubber Roof and want to apply another layer of Torch Down over it, then make sure there is no Aluminum Asphalt paint or Silver Paint on it. You can not Torch another layer over the existing layer if there is any paint on it.
Make sure the flashing is done right and in good condition before adding a second layer.
Waterproofing and Leak Specialists