TogCheck
Combined TOG result

Cormar Hampstead Supreme and Duralay Durafit 650: combined TOG for underfloor heating

The combined TOG for Cormar Hampstead Supreme over Duralay Durafit 650, worked against the UHMA underfloor heating rule.

1.52.5
1.4TOG in situ
Pass · limit 2.5
Published TOG stack (carpet + underlay)
carpet 1.3
underlay 1.1
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 1.4, under the 2.5 TOG limit, so Cormar Hampstead Supreme with Duralay Durafit 650 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
CarpetCormar Hampstead Supreme (1.3 TOG)
UnderlayDuralay Durafit 650 (1.1 TOG)
Published sum2.4 TOG
UHMA in-situ correctionminus 1 TOG
Combined in-situ TOG1.4 TOG
Standard UFH limit2.5 TOG
Heat pump targetunder 1.5 TOG

Cormar Hampstead Supreme is rated 1.3 TOG and Duralay Durafit 650 is rated 1.1 TOG. Laid together the combination is what the underfloor heating has to warm through.

The published TOG figures add to 2.4. The UHMA rule subtracts 1 TOG because tests showed real in-situ resistance runs about a TOG below the paper sum, giving 1.4 TOG. That clears both the standard limit and the tighter heat-pump target.

Related checks
Cormar Hampstead Supreme TOG value1.3 TOGDuralay Durafit 650 TOG rating1.1 TOGCormar Pimlico with Duralay Durafit 6501.1 TOG, passCormar Primo Textures Ribbed with Duralay Durafit 6501.1 TOG, passCormar Primo Textures Weave with Duralay Durafit 6501 TOG, passCormar Apollo Plus with Duralay Durafit 6501.2 TOG, pass

Sources: UHMA guidance on underfloor heating with carpet and underlay (combined-TOG rule) · How to calculate a combined TOG (UHMA formula, worked) · Cormar Carpets published carpet TOG values · Interfloor / Duralay Durafit 650 underlay datasheet