Installation of PermaBASE over foundation walls
The 1/2" PermaBASE boards can be installed below ground level over extruded polystyrene boards that are themselves installed over a foundation wall, under the following conditions.
- That the PermaBASE boards be fully supported, over their entire surface, by the polystyrene boards.
- That the PermaBASE boards be installed using our specially designed PermaBASE screws, every 8" o.c. (200 mm), over furring channels (wood or galvanized metal 20 gauge or thicker) that comply with the following requirements:
- That the furring strips be spaced at a maximum of 24" (610 mm) o.c.
- That the furring strips have the same thickness (or depth) as the polystyrene board.
- That the furring strips be in full contact with the foundation wall.
- That the furring strip is affixed to the foundation wall with the proper fasteners and in sufficient number to provide adequate support for the board, its finish, and other building loads.
- That the furring strips be corrosion or rot proof.
- That the extruded polystyrene boards be approved for exterior use, below ground, and that they have a compressive strength of 20 psi (140 kPa) or higher when tested according to ASTM D1621.
- That the PermaBASE boards are installed below ground at a maximum depth of 10' (3 m).
- That the water table level is at all times be below the base of the foundation wall.
- That the base of the foundation wall is properly drained in order to avoid any accumulation of water and consequently an added pressure on the wall.
- That the wall design is in conformance with the applicable and most up-to-date local, provincial, and federal building codes where the project is located.
The PermaBASE boards are resistant to water but are not water impermeable or waterproof and cannot be considered a vapor barrier. Where a wall or cavity must be kept dry, use proper water-resistant membranes, in conformance with the applicable and most up-to-date local, provincial, and federal building codes where the project is located. Some waterproofing compounds, sealants, or adhesives may contain solvents or petroleum distillates. These may damage the polystyrene. Please contact the manufacturers of these products to verify their compatibility with polystyrene and concrete. The PermaBASE boards are not structural boards.