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Why do I need Slab Edge Insulation?

Insulating the edge of your concrete slab is important because that’s where most of the heat (up to 80% according to BRANZ), escapes. We recommend insulating the edge of your slab in all cases, however where you definitely need edge insulation;

  • Updated H1 requirements

  • If you want to achieve a higher Homestar rating.

  • If you’re planning on using in-slab heating.

The New Zealand Building Code clause H1 (Energy Efficiency) has been updated.  In accordance with H1/AS1 and H1/VM1 there are new minimum R-values for slab-on-ground floors.  The appendix of each provides the R-Value of common concrete slab floors and replaces the previous minimum of R1.3.

Of course we recommend all concrete floor slabs, and all aspects of a building, should ideally be constructed to be more energy efficient.  This is even more important when heating slabs as well.

We offer a range of proven systems with various top details to suit your build design.

Heat loss through a slab to the outside (source: Design Navigator)

Thermal model showing  heat loss through traditional concrete slab (source: BRANZ)

Thermal model showing  heat loss through traditional concrete slab with slab edge insulation (source: BRANZ)

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