How to Install Bitumen Roofing Sheets

APP Roofing

• 1

  Measure and cut lengths of roofing one at a time unless you have a huge work area. Allow cut pieces to rest for 30 minutes if they are still curved from being tightly rolled.

• 2

  Re-roll the strip so that the underside of the fabric is on the outside of the roll. APP (atactic polypropylene) roofing forms a surface bond with the asphalt layer beneath. You need access to the complete underside surface to make a tight bond.

• 3

  Apply heat from a torch one section at a time, melting the asphalt layer on the underside of the fabric enough for it to adhere to the roof. Work a few feet at a time to ensure adhesion. Anchor the finished strip with lengths of 2-by-4-inch boards until the seal is tight. Begin the next strip, overlapping it by several inches.

SBS Roofing

• 4

  Measure, cut and rest strips of SBS as you would for APP. The construction of SBS (styrene butadiene styrene) roofing is different from APP. Rather than forming a fairly rigid surface layer with asphalt underneath, SBS forms a network within the bitumen, or asphalt, itself. The SBS fabric will form a bond with the hot asphalt or adhesive you are using.

• 5

  Roll roofing strips so the underside is on the outside.

• 6

  Spread hot asphalt or adhesive -- depending on the size of the strip -- on the roof and roll out the roofing fabric. Anchor it until you are certain a solid bond has formed between fabric and fixative.

Self-Adhesive Bitumen Sheets

• 7

  Heed manufacturers' recommendations for the best places to use this essentially peel-and-stick roofing fabric, especially relating to climate conditions.

• 8

  Apply self-adhesive bitumen sheets only when outside temperatures meet manufacturers' recommendations and follow other instructions governing workmanship. Violating these recommendations may invalidate warranties.

• 9

  Plan to install this roofing during a prolonged period of good weather, to ensure good adhesion.