Underlay TOG rating

Cormar Woodland Heathers Deluxe TOG value and underfloor heating

The published Cormar TOG value for Cormar Woodland Heathers Deluxe and the underlay budget it leaves over a heated floor.

1.7TOG

Suitable for UFH

Leaves 0.8 TOG of the combined budget for the carpet on top before the 2.5 TOG limit is reached.

PassMarginalFail

Published value

Range	Cormar Woodland Heathers Deluxe
Construction	wool-blend berber
TOG rating	1.7 TOG
Max underlay TOG for UFH	1.8 TOG

Cormar Woodland Heathers Deluxe is a wool-blend berber with a published TOG value of 1.7. A deeper wool-blend berber at 1.7 TOG. Only the lowest-TOG underlays keep this within the combined limit.

Using the UHMA rule, in-situ resistance is carpet plus underlay minus 1. To keep Cormar Woodland Heathers Deluxe under the 2.5 TOG limit the underlay must be no more than 1.8 TOG.

TOG measures thermal resistance, so a low number means heat passes through easily. For a floor covering over underfloor heating that is what you want. A comfort underlay chosen for warmth underfoot does the opposite job and is the usual reason a heated floor underperforms after a carpet goes down.

Underlay pairings

Cormar Woodland Heathers Deluxe with Duralay Technics 5combined 1.26 TOG Cormar Woodland Heathers Deluxe with Duralay Heatflow for Carpetcombined 1.45 TOG Cormar Woodland Heathers Deluxe with Tredaire King (Duralay King)combined 1.5 TOG Cormar Woodland Heathers Deluxe with Duralay Durafit 650combined 1.8 TOG Cormar Woodland Heathers Deluxe with Tredaire Softwalkcombined 3.39 TOG Cormar Woodland Heathers Deluxe with Tredaire Dreamwalkcombined 3.83 TOG

Sources: Cormar Carpets published carpet TOG values · UHMA guidance on underfloor heating with carpet and underlay (combined-TOG rule)