Ballasted Waterproofing PRMA / Concrete Deck

Installation & Design Considerations

• Ballast, smooth 2” x 2’ x 2’ concrete pavers, water worn gravel or crushed stone, hold system in place.
• See ANSI/RMA/SPRI, Wind Design Guide for Ballasted Single-Ply Roofing Systems for ballast weight requirements.
• Install ballast immediately over pedestals to hold system in place.
• Protective mat is loosely laid between the ballast and insulation.
• FOAMULAR® 400 or 600 insulation is loosely laid over FOAMULAR® 404 or 604.
• FOAMULAR® 404 or 604 insulation is loosely laid, rain channels down, over a nondegradable, bond breaking slip sheet as recommended by the membrane manufacturer.
• Waterproofing membrane is applied over the concrete deck.
• The need for and placement of vapor retarders should be determined by the building designer.
• Alternate deck materials; all FOAMULAR® roof insulation can be installed directly on concrete, gypsum, wood and Tectum decks.
• See Underwriters Laboratories or Factory Mutual listings for complete details.