Bituminous felt is a form of waterproof sheeting that is used to cover flat roofs, or as an underlay beneath slate or tile roofing.

What is the best felt for flat roof?

EPDM Membranes

Quite possibly the best flat roofing membrane, EPDM is a relatively low-cost flat roof material that offers a number of significant advantages. Clean, straightforward installation, incredible strength, a long lifespan, and a smart finish combine to make EPDM membranes a difficult one to beat.

Is felt OK for flat roofs?

Overall, felt roofing can be a good option for flat roofed buildings in a range of sectors including residential and commercial roofing projects. It is waterproof, weatherproof and very cheap to install, replace as well as repair.