Roofs - Insulation Overlays
Roofs - Insulation Overlays
| Accepted Materials for a RoofStar Guarantee
The tables and products shown below provide basic material data and links to more information about the materials, including manufacturers' published Technical Data sheets, but this information is not intended for use as a comparison of material performance or quality. It is the sole responsibility of the Design Authority to assess the performance capability and material suitability for specific design requirements. The materials listed are those which have been accepted by the RoofStar Guarantee Program (RCABC Guarantee Corp., or RGC) for use in a roof or grade-level waterproofing system that will qualify for a RoofStar Guarantee. The acceptance of these materials by the RGC (RoofStar Guarantee Program) in no way reflects on the quality or performance of other materials not listed. The materials and guideline specifications are listed under the name of the manufacturer and/or supplier of the primary membrane material, with the exception of BUR membranes for which the reader will find RoofStar Guarantee Program guidelines on traditional built-up roofing systems (BUR) incorporating organic and glass felt primary membranes. |
Insulation overlays are used to separate the roof membrane from the primary insulation, usually for one of two reasons:
- to prevent the insulation from affecting the performance of the roof membrane
- to prevent the roof membrane and / or the method of application from affecting the insulation
The insulation can affect the performance of the roof membrane in the following ways:
- the insulation may be incompatible with the membrane, resulting in a loss of physical properties
- different coefficients of thermal expansion may result in membrane splits / cracks.
The roof membrane and / or the method of application can affect the insulation in the following ways:
- the insulation may not be capable of withstanding asphalt application temperatures and may “burn-out”
- some insulations will not accommodate direct torch-applied membranes
- insulations that are too “soft” may result in delamination or damage to the membrane or insulation when exposed to heavy loads or traffic
- the solvents and adhesives used for flexible membranes may adversely affect the insulation.
NOTE: All hot asphalt-adhered asphaltic membranes (built-up roofing, modified bitumen, etc.) require an insulation overlay over heat sensitive insulations and heat insensitive foamed insulation. RoofStar Guarantee Standards for heat sensitive insulation require a two-layer overlay board for a five (5) or ten (10) year RoofStar Guarantee. The RoofStar Guarantee Standards require the use of a two-layer overlay board over heat sensitive insulation in all cases, and also requires a single-layer overlay board application over heat insensitive insulation for all hot asphalt-adhered membranes. For single-ply, non-asphaltic membrane roofing systems, the membrane manufacturer should be consulted for proprietary options.
Fibreboard Template:Materials - Insulation Overlay (Fibreboard)
Proprietary Insulation Overlay Boards Template:Materials - Insulation Overlay (Proprietary)