The dark art of defining R Value is influenced by many factors in a foundation floor. Replacing the harmful polystyrene with encapsulated air in QPOD™ Flooring System is considered to improve the thermal potential of flooring insulation. As per the H1 AS1 clause 2.1.5 states concrete slab on grade floors are deemed to achieve a construction Rvalue of 1.3 and can be assumed to comply as an accepted solution with no need for any verification. Where under floor heating is proposed, the designer will need to specifically calculate the R-value in accordance with NZS4214 to satisfy the build code requirements. Some informative R-values can be found here to assist in the designer carrying out the verification.
Area/perimeter ratio
Ratio 1.3 1.9 2.2 2.5 2.8 3.1 4.0
R-Value with R1.0 perimeter edge insulation 1.4 1.8 1.9 2.1 2.3 2.4 2.9
R-Value with no perimeter edge insulation 1.0 1.2 1.3 1.5 1.6 1.7 2.1
3rd party insulation systems like MagRoc Insulfound & ThermaSlab can be used in conjunction with QPOD™ Flooring System to improve R Value substantially suitable for underfloor heating solutions.