APP Modified Bitumen Torch Grade Membrane for Smooth Roof InstallationAPP modified bitumen membranes came to the United States from Europe in the late 1970s. This technology and its installation method have been around in the construction industry for over 30 years. When Ridge Top Exteriors Milwaukee installs this type of roofing system there are basic safety measures taken before we get started. APP modified bitumen torch grade membranes are not installed without careful review and implementation of all applicable safety and fire watch requirements. Our crews are fully familiar of Propane Gas Equipment Storage and Handling guideline and Workers’ Safety Precautions learned in their extensive training is followed throughout the process. As with all installation of a roofing system, safety is a key element. Ridge Top Exteriors will remove all potentially flammable articles from the work area for fire prevention.
Step 1: Ridge Top Exteriors PreparationThe surface over which the membrane is to be installed will be cleaned, smoothed and dried, and prepared in accordance with the USP 160 specification manual.
Suitable torching substrates are:structural concrete
self-adhered/mechanically fastened/asphalt-adhered base sheets and ply sheets
Gypsum cover boards.
Substrates not suitable for torching are:Insulation boards such as polisocyanurate, perlite and wood fibre.
Fresh asphalt glazes or flood coats
Solvent-based cold adhesives or mastics Other flammable substrates such as wood, plywood and oriented strand boards APP membranes cannot be applied during adverse weather or without precautionary measures and temperatures below 45 degrees Fahrenheit. There is also a reference on the cold weather precautions section of the USP 160 specifications manual. For slopes less than 3 inches per foot, Ridge Top Exteriors installs cap sheets perpendicular to the slope. For slopes 3 inches and over, APP torch grade membranes will run vertically or parallel to the roof slope. All laps are parallel or perpendicular to the slope above the roof so that water is never running against the lap edge.