Brockway Orion Twist (1.61 TOG) with Duralay Technics 6 (0.66 TOG) gives a combined 1.27 in-situ TOG. Whether that passes the 2.5 TOG underfloor heating limit and what to do.

Updated 05 September 2026.

Combined TOG result

Brockway Orion Twist and Duralay Technics 6: combined TOG for underfloor heating

The combined TOG for Brockway Orion Twist over Duralay Technics 6, worked against the UHMA underfloor heating rule.

1.52.5
1.27TOG in situ
Pass · limit 2.5
Published TOG stack (carpet + underlay)
carpet 1.61
underlay 0.66
limit

Combined against the UHMA 2.5 TOG underfloor-heating limit. Under 1.5 also suits a low-temperature heat pump.

Carpet TOGUnderlay TOGPassMarginalFail
Combined in-situ TOG is 1.27, under the 2.5 TOG limit, so Brockway Orion Twist with Duralay Technics 6 is suitable for a standard underfloor heating system. It is also under 1.5 TOG, so it suits a low-temperature heat pump run.
The combined-TOG calculation
CarpetBrockway Orion Twist (1.61 TOG)
UnderlayDuralay Technics 6 (0.66 TOG)
Published sum2.27 TOG
UHMA in-situ correctionminus 1 TOG
Combined in-situ TOG1.27 TOG
Standard UFH limit2.5 TOG
Heat pump targetunder 1.5 TOG

Brockway Orion Twist is rated 1.61 TOG and Duralay Technics 6 is rated 0.66 TOG. Laid together the combination is what the underfloor heating has to warm through.

The published TOG figures add to 2.27. The UHMA rule subtracts 1 TOG because tests showed real in-situ resistance runs about a TOG below the paper sum, giving 1.27 TOG. That clears both the standard limit and the tighter heat-pump target.

Related checks

Questions and answers

Brockway Orion Twist and Duralay Technics 6: combined TOG for underfloor heating?

Combined in-situ TOG is 1.27, under the 2.5 TOG limit, so Brockway Orion Twist with Duralay Technics 6 is suitable for a standard underfloor heating system. It is also under 1.5 TOG, so it suits a low-temperature heat pump run.