Arkalow – SIPS as flooring material?

[Anonymous]

Now we have Planning permission, we are detailing the construction for our 'Eco house'. We have encountered a curious discrepancy. The inner structure of the house's three storey section will have a rigid self-supporting frame, to span the 15m x 10m open-plan living area. This could be of steel, glulam or (preferably) green oak. The basement area is a simple one storey box with a maximum span of 3.5m.

The outer skin could be SIPs, for speed of construction, insulation and airtightness. Although we are detailing the floors and flat roofs as being constructed with timber I-beams, my web research suggests that SIPS can be used as a flooring material. Uniformity and speed of construction, together with the eliminating of cold-bridging, seem logical.

However, one structural engineer currently draughting our frame design is of the categoric opinion that SIPS cannot be used for flooring.

Several American websites show the office staff and even an elephant standing on top of SIPS panels, and other websites mention SIPS as flooring material, but without giving details.

Does anyone here have experience of SIPS used horizontally?

[Author]

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