TogCheck
Underlay TOG rating

Cormar Trilogy Austen TOG value and underfloor heating

The published Cormar TOG value for Cormar Trilogy Austen and the underlay budget it leaves over a heated floor.

1.52.5
1.2TOG
Suitable for UFH

Leaves 1.3 TOG of the combined budget for the carpet on top before the 2.5 TOG limit is reached.

PassMarginalFail
Published value
RangeCormar Trilogy Austen
Constructionwool-blend twist
TOG rating1.2 TOG
Max underlay TOG for UFH2.3 TOG

Cormar Trilogy Austen is a wool-blend twist with a published TOG value of 1.2. A Trilogy wool-blend twist rated 1.2 TOG, within range for a heated floor with the right underlay.

Using the UHMA rule, in-situ resistance is carpet plus underlay minus 1. To keep Cormar Trilogy Austen under the 2.5 TOG limit the underlay must be no more than 2.3 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 Trilogy Austen with Duralay Technics 5combined 0.76 TOGCormar Trilogy Austen with Duralay Heatflow for Carpetcombined 0.95 TOGCormar Trilogy Austen with Tredaire King (Duralay King)combined 1 TOGCormar Trilogy Austen with Duralay Durafit 650combined 1.3 TOGCormar Trilogy Austen with Tredaire Softwalkcombined 2.89 TOGCormar Trilogy Austen with Tredaire Dreamwalkcombined 3.33 TOG

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