TogCheck
Combined TOG result

Cormar Apollo Plus and Cloud 9 Contract: combined TOG for underfloor heating

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

1.52.5
2.2TOG in situ
Marginal · limit 2.5
Published TOG stack (carpet + underlay)
carpet 1.1
underlay 2.1
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 2.2, under the 2.5 TOG limit, so Cormar Apollo Plus with Cloud 9 Contract is suitable for a standard underfloor heating system. It is above 1.5 TOG, so on a low-temperature heat pump run choose a thinner underlay.
The combined-TOG calculation
CarpetCormar Apollo Plus (1.1 TOG)
UnderlayCloud 9 Contract (2.1 TOG)
Published sum3.2 TOG
UHMA in-situ correctionminus 1 TOG
Combined in-situ TOG2.2 TOG
Standard UFH limit2.5 TOG
Heat pump targetunder 1.5 TOG

Cormar Apollo Plus is rated 1.1 TOG and Cloud 9 Contract is rated 2.1 TOG. Laid together the combination is what the underfloor heating has to warm through.

The published TOG figures add to 3.2. The UHMA rule subtracts 1 TOG because tests showed real in-situ resistance runs about a TOG below the paper sum, giving 2.2 TOG. On a heat pump running low flow temperatures the floor has less heat to push, so aim under 1.5 TOG and prefer the thinnest underlay in this range.

Related checks

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 Contract underlay specification