01 May 1999
(1) Vapors and Fumes. Solvent-based adhesives (for fully adhered systems) are flammable
and their odor may be objectionable to occupants. Shut off air intakes or take other preventative
measures to avoid fumes entering occupied spaces.
(2) Contamination. Avoid contamination of work in progress and finished work by wind blown
particulates, especially from aggregate removal on adjacent areas.
b. Pre-roofing Conference. A conference should be held prior to construction. Representatives
of the designer, user, roofing contractor, general contractor, materials manufacturer, field inspector
and other related subcontractors should be present. Discussions should include protection of the thin
membrane after installation and how nightly water cutoffs will be.
Shop Drawing Submittals
(1) Drawings. Drawings of intersections of expansion joints, curbs, edging, flashing, and
coping should be required especially when polymer clad metal is used. Details should be detail
specific and dimensioned not the manufacturer's standard detail plates.
(2) Layout Diagram. Since some of these products are available in fire rated (FR) and non-
fire rated sheeting, determine which is needed for each roof area and include layout on shop drawing.
(Generally FR will be required on steeper slopes.)
(3) Nailers. Nailers must be anchored to resist 270 N/m (200 lb/ft.) for adhered thermoplastic
systems and 300 N/m (300 lb/ft) for mechanically anchored systems. Submit details of how this will be
achieved (dimensions of nailers, frequency and size of fasteners). Anchorage should meet the greater
of the above requirements and FM 1-49 (Perimeter Flashings) recommendations.
d. Design Submittal Requirements and Checklist. Require the manufacturer to verify in writing
that the proposed system is compatible with the roof deck, vapor retarder, insulation, and is
appropriate for this specific application. On major roofing projects require quality assurance inspection.
Require evidence of compliance with fire ratings, wind loads, or other specified code requirements.
e. Field Review and Observation.
(1) Inspection. Each of the various thermoplastic systems has special application techniques.
On large projects, representatives of the manufacturer should be present to verify application
techniques and to train the inspector. The manufacturer foreman's manual should be provided to the
(2) Welds. Daily field tests of welded seams are recommended.
(3) Nailers. Nailers must be installed as specified.
(4) Stress Relaxation. Before it is attached, the membrane must be unrolled and allowed to
relax for at least 1/2 hour when the ambient temperature is above 15C (60F) and up to 2 hours at
(5) Finished Work Protection. Prevent tracking of bitumen onto new membrane from wheeled
roof equipment or roofer's boots.
7-5. MAINTENANCE CONSIDERATIONS.
a. General. Thermoplastic single-ply membranes are designed for weather resistance and do
not require coating during their life. (Some CSPE sheets have suffered algae attack and may show
crazing under field exposure. Primers and coatings may help.) Exhausted solvents, oils, particulates,
hot air, or steam will damage most thermoplastic membranes.