What is the difference between a cold loft and a warm loft?
In a cold loft the insulation sits on the loft floor, and the roof space above stays cold and ventilated. In a warm loft the insulation follows the roof slope, so the loft itself is inside the heated envelope.
Which is better?
| Cold loft (floor) | Warm loft (rafters) | |
|---|---|---|
| Cost | Low | High |
| Heat saved per pound | Highest | Lower |
| Loft temperature | Cold | Close to the house |
| Best for | Storage only | Used rooms, ducting |
| Condensation risk | Managed by ventilation | Managed by build-up design |
Can I have both?
You can, but it is rarely worth paying for both. Pick the one that matches how the loft is used.
Related services
Sources: Energy Saving Trust: roof and loft insulation; Which?: loft insulation costs and savings; LABC: building regulation requirements for loft insulation; GOV.UK: extending the ECO4 end date, government response; GOV.UK: VAT on energy-saving materials (notice 708/6); Property Care Association: spray foam guidance.
