Cormar Natural Berber Elite and Duralay Heatflow for Carpet: combined TOG for underfloor heating
The combined TOG for Cormar Natural Berber Elite over Duralay Heatflow for Carpet, 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 Natural Berber Elite (1.6 TOG) |
|---|---|
| Underlay | Duralay Heatflow for Carpet (0.75 TOG) |
| Published sum | 2.35 TOG |
| UHMA in-situ correction | minus 1 TOG |
| Combined in-situ TOG | 1.35 TOG |
| Standard UFH limit | 2.5 TOG |
| Heat pump target | under 1.5 TOG |
Cormar Natural Berber Elite is rated 1.6 TOG and Duralay Heatflow for Carpet is rated 0.75 TOG. Laid together the combination is what the underfloor heating has to warm through.
The published TOG figures add to 2.35. The UHMA rule subtracts 1 TOG because tests showed real in-situ resistance runs about a TOG below the paper sum, giving 1.35 TOG. That clears both the standard limit and the tighter heat-pump target.
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 Heatflow for Carpet datasheet