Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 23·5.9
Insulant compressive strength and water absorption
Insulation must have sufficient compressive strength to withstand slab weight, floor loading, and construction loads. Insulation placed below the DPM must have low water absorption and may need to be resistant to ground contaminants.
Insulants should have sufficient compressive strength to resist the weight of the slab, the anticipated floor loading as well as any possible overloading during construction. In order to resist degradation, it is essential that insulation placed below the DPM has low water absorption. If necessary the insulant should be resistant to contaminants in the ground.
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