Can the black insulation board be used to glue the EPDM rubber roofing to?

The suitability of using a black insulation board as a substrate for adhering EPDM rubber roofing depends on the specific material composition of the insulation board.

Suitable Substrates for EPDM Roofing

EPDM membranes adhere well to substrates that are clean, dry, and compatible with the adhesive used. Commonly recommended substrates include:

Plywood or OSB Board: These provide a stable and smooth surface for adhesion.

Polyisocyanurate Insulation Boards with Fiberglass Facing: These are compatible with EPDM adhesives and offer added insulation benefits.

High-Density Wood Fiberboard: This material is also suitable for EPDM application.

Considerations for Black Insulation Boards

The term "black insulation board" can refer to various materials, and its suitability as a substrate for EPDM depends on its composition:

Asphalt-Based or Tar-Containing Boards: EPDM should not be bonded directly over asphalt, tar, or similar petroleum-based products, as the oils can cause the EPDM to swell and fail.

Polystyrene Insulation Boards: These are generally unsuitable for direct adhesion with EPDM membranes. Solvent-based adhesives can melt polystyrene, and water-based adhesives may not adhere properly. If polystyrene insulation is used, it should be covered with a suitable cover board, such as 13mm high-density wood fiberboard, before applying the EPDM membrane.

Recommendations

Identify the Material: Determine the exact composition of your black insulation board.

Check for Compatibility: If the board is made of polyisocyanurate with a fiberglass facing, it is likely suitable for EPDM adhesion. However, if it contains asphalt, tar, or is made of polystyrene, it is not recommended for direct adhesion.

Use a Cover Board if Necessary: For unsuitable substrates, install an appropriate cover board, such as plywood, OSB, or high-density wood fiberboard, before applying the EPDM membrane.