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Insulation funding: what can actually be confirmed

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Insulation can reduce heat loss, but neither a postcode nor a short questionnaire proves that work will be free or suitable. The Energy Saving Trust says an uninsulated roof can lose around 25% of a home’s heat, while around 33% can be lost through walls. Actual savings depend on the property and existing insulation.

Current reference facts

Loft insulation

270mm recommended depth

Energy Saving Trust gives typical Great Britain costs of about £750 from no insulation to 270mm, or £600 to top up from 120mm. Its current top-up saving example is about £17 a year, not hundreds.

Cavity wall insulation

About £2,200 typical cost

Suitability requires a survey. Energy Saving Trust says around a third of heat can be lost through walls.

Solid wall insulation

About £12,000 internal / £15,000 external

Typical three-bedroom semi-detached reference costs; the correct approach and saving are property-specific.

Funding is not automatic

ECO4 suppliers and Local Grant councils decide what is suitable and funded. ECO may require a contribution. Local Grant residents generally do not pay, although landlords may be asked to contribute.

Frequently asked questions

Can WarmHome UK promise free insulation?

No. WarmHome UK can only identify a potential route. A supplier or council must confirm the property, measure, funding and any contribution.

Can savings be predicted from a postcode?

No. Savings depend on the dwelling, current insulation, heating, energy prices and household use.

Check for a potential insulation route

Results are indicative and link to the official scheme rules.

Run the Indicative Checker