CertainTeed FlintBoard® ISO WF Composite Polyisocyanurate/Wood Fiberboard Roof Insulation is a rigid board insulation for hot asphalt BUR, modified bitumen and single ply roofing systems.

Consult membrane manufacturer for suitability and system requirements.

FlintBoard ISO WF features a closed-cell polyiso core bonded to 1/2" high-density wood fiberboard with a fiber-reinforced felt facer on the bottom side. The wood fiberboard top makes FlintBoard ISO WF an ideal recovery board, and when used as the second layer over FlintBoard ISO eliminates the need for a separate overlay board, yet retains the benefits of a second layer of ISO.

FlintBoard ISO WF is a recommended roof insulation in conjunction with CertainTeed Commercial Roofing Systems including Flintlastic® Roof Systems.

Technical Information

FlintBoard ISO WF is offered in a variety of thicknesses, providing long-term thermal resistance (LTTR) values from 7.3 to 26.4. Available in 4' x 4' (1220mm x 1220mm) and 4' x 8' (1220mm x 2440mm) panels.

For additional technical resources please refer to the CertainTeed Commercial Roof Systems Manual.


Before installation begins, the roof deck must be firm, well attached, even, clean and dry.

For detailed installation instructions please refer to the CertainTeed FlintBoard product brochure and to the CertainTeed Commercial Roof Systems Manual. Refer also to Technical Bulletin CT-ISO-08-02.

Warranty Details

Please refer to the document provided for all warranty information.

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