Torch Down Roofing Underlayment

These steps show a torch down method which looks a bit scary but actually is not too difficult.

Torch down roofing underlayment.

This underlayment helps prevent the roof from developing condensation or moisture issues. Secure it with roofing nails and then apply the torch down. What type of underlayment should i use. If you install the smooth product cover it with aluminum coating.

This membrane contains a core of nonwoven polyester mat that resists splits and tears. The mat is coated with durable app modified bitumen and is designed for torch down application by professional roofing. Gaf tri ply app smooth is a strong resilient membrane that is suitable for new or reroofing projects as well as for use as flashing. Priming the underlayment is not needed.

This video shows you how to use a torch and also tar to make a repair on a modified bitumen rubber flat roof. As long as it is installed correctly bitumen prevents moisture build up without needing constant maintenance. Gafglas 75 base sheet for built up roofing bur is a premium roofing sheet with a strong fiberglass mat to prevent asphalt bleed through. The roofing professional will lay down an overlay board or cover board next to support the torch down roofing membrane.

Care must be taken to apply the overlay board correctly to prevent ponding which is when the roof is not level. I originally was going to use ice and water shield but don t think i want to put torch down on top of that. Use flashings approved by your building department. It is best to use 75 glass base underlayment.

The sealed sheet also serves as an effective flame retarder for the application of torch applied modified bitumen membranes. Renting a large propane torch is. Torch down roofing is a type of roofing material that has been designed for low angle or flat roofs. Torch down roofing consists of modified bitumen which is similar to asphalt.

Modified bitumen roofing may have a granular surface as shown here or it may be smooth.