TogCheck
Combined TOG result

Cormar Primo Plus and Cloud 9 Radiance: combined TOG for underfloor heating

The combined TOG for Cormar Primo Plus over Cloud 9 Radiance, worked against the UHMA underfloor heating rule.

1.52.5
1.4TOG in situ
Pass · limit 2.5
Published TOG stack (carpet + underlay)
carpet 1.1
underlay 1.3
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 Primo Plus with Cloud 9 Radiance 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 Primo Plus (1.1 TOG)
UnderlayCloud 9 Radiance (1.3 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 Primo Plus is rated 1.1 TOG and Cloud 9 Radiance is rated 1.3 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 Primo Plus TOG value1.1 TOGCloud 9 Radiance TOG rating1.3 TOGCormar Pimlico with Cloud 9 Radiance1.3 TOG, passCormar Primo Textures Ribbed with Cloud 9 Radiance1.3 TOG, passCormar Primo Textures Weave with Cloud 9 Radiance1.2 TOG, passCormar Apollo Plus with Cloud 9 Radiance1.4 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 · Ball & Young Cloud 9 Radiance underlay specification (6 mm, 1.3 TOG, underfloor-heating rated)