Selecting the right cover board for your single ply roofing application can have a major impact on performance and longevity of the system. Cover boards provide several purposes within a roof assembly including:
- Insulation protection (against crushing) and thermal improvement
- Strength and durability (hail and impact protection)
- Fire resistance
- Sound resistance
- Dimensional stability of the insulation system
In March 2000, the National Roofing Contractors Association (NRCA) endorsed and recommended the use of cover boards over polyisocyanurate insulation, which superseded previous NRCA Technical Bulletins and revisions on the topic, dating back to 1978.
There are several cover board options for single ply roof assemblies, each with their own sets of pros and cons. Four main types of cover board materials for single ply roof systems include glass-mat faced gypsum, fiber-reinforced gypsum, high density polyisocyanurate and wood fiberboard. The pros and cons of these four main types are described below:
Understanding the differences in these materials will contribute to the success of the design, installation and performance of your single ply roof system. All roof systems present unique challenges to achieving a long lasting, thermally efficient building covering. For specific assistance in selecting the material that is appropriate for your roofing application, contact Gale Associates.