Cormar Zenith and Cloud 9 Contract: combined TOG for underfloor heating
The combined TOG for Cormar Zenith over Cloud 9 Contract, worked against the UHMA underfloor heating rule.
Combined against the UHMA 2.5 TOG underfloor-heating limit. Under 1.5 also suits a low-temperature heat pump.
| Carpet | Cormar Zenith (1.5 TOG) |
|---|---|
| Underlay | Cloud 9 Contract (2.1 TOG) |
| Published sum | 3.6 TOG |
| UHMA in-situ correction | minus 1 TOG |
| Combined in-situ TOG | 2.6 TOG |
| Standard UFH limit | 2.5 TOG |
| Heat pump target | under 1.5 TOG |
Cormar Zenith is rated 1.5 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 3.6, and even after the UHMA 1 TOG in-situ correction the pair sits at 2.6 TOG, 0.1 TOG over the limit. The carpet is fine; the underlay is doing the damage. Keep Cormar Zenith and drop to a low-TOG underlay such as Duralay Heatflow for Carpet (0.75 TOG) or Duralay Technics 5 (0.56 TOG), which brings the combined figure back into range.
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