Brockway Orion Twist has a published TOG value of 1.61. The underlay TOG it can take and stay under the 2.5 TOG combined limit for underfloor heating.

Updated 05 September 2026.

Underlay TOG rating

Brockway Orion Twist TOG value and underfloor heating

The published Cormar TOG value for Brockway Orion Twist and the underlay budget it leaves over a heated floor.

1.52.5
1.61TOG
Suitable for UFH

Leaves 0.89 TOG of the combined budget for the carpet on top before the 2.5 TOG limit is reached.

PassMarginalFail
Published value
RangeBrockway Orion Twist
Construction80% wool wool-blend twist
TOG rating1.61 TOG
Max underlay TOG for UFH1.89 TOG

Brockway Orion Twist is a 80% wool wool-blend twist with a published TOG value of 1.61. Orion Twist is an 80% wool blend twist rated 1.61 TOG. Its resistance means only the lowest-TOG underlays keep the pair under the combined limit over a heated floor.

Using the UHMA rule, in-situ resistance is carpet plus underlay minus 1. To keep Brockway Orion Twist under the 2.5 TOG limit the underlay must be no more than 1.89 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

Questions and answers

What is the range of the Brockway Orion Twist TOG value and underfloor heating?

Brockway Orion Twist

What is the construction of the Brockway Orion Twist TOG value and underfloor heating?

80% wool wool-blend twist

What is the tog rating of the Brockway Orion Twist TOG value and underfloor heating?

1.61 TOG

What is the max underlay tog for ufh of the Brockway Orion Twist TOG value and underfloor heating?

1.89 TOG