Written by: David Shong, Insulfoam Architectural & Engineering Technical Specialist
The Cold Climate Housing Research Center, CCHRC, in Fairbanks, AK constructed an addition to their facility in the spring of 2012. The project Engineers specified 12″ of InsulFoam GF EPS39 which has a minimum compressive resistance of 2,160 psf @ 1% strain as a sub-base and below slab insulation. EPS39 was placed around the perimeter under the exterior wall footings and within the zones of influence of interior columns that required higher bearing capacity to withstand the axial loads of the walls,roof and snow load.
The rest of the areas that were simply supporting the 6″ floor slab used 12″ of EPS22 (1051 psf @ 1% strain). They were originally considering only 9″ of EPS46 (2,678 psf @ 1% strain) for the entire building footprint, but were happily surprised to hear the idea of using a lower density under the floor slabs where the decreased dead loads justified a lower EPS density.
They ended up being able to install 12″ of EPS under the entire footprint for less than the original budget which provided more insulation while saving on initial costs as well as long term energy expenditures.