Loft insulation cost, savings and payback

What loft insulation typically costs to install in a UK home, how much it can save on heating, and the grant schemes that may cover it.

Loft insulation slows heat escaping through the roof, which is one of the largest heat-loss paths in an uninsulated house. In a typical loft the recommended depth is around 270 mm of mineral wool.

It is usually the cheapest fabric measure to fit and one of the quickest to pay back, because the roof is easy to reach and the material is inexpensive.

Across the 10015 energy certificates in our dataset, 5.7% are recorded as having little or no loft insulation. This is an indicative figure from the certificates we hold, not a national statistic.

Typical UK cost

Item	Typical cost	Notes
Loft insulation (professional install, typical semi/terrace)	£300–£700	Roll-out mineral wool to ~270 mm in an accessible loft.
Topping up existing thin insulation to the recommended depth	£200–£500	Cheaper where some insulation is already present.

Cost ranges are indicative and attributed to Energy Saving Trust: Insulation. Prices vary by property, region and installer – always get quotes and check the official source.

Typical saving

The Energy Saving Trust estimates loft insulation can save roughly £25 to £45 a year on heating in a typical home, more where the loft was previously uninsulated.

Saving figures are indicative and attributed to Energy Saving Trust: Insulation. Check the official source.

Payback

Because the cost is low, payback is often within a few years; the exact figure depends on how much insulation was there before and how the home is heated.

What affects the price

How much (if any) insulation is already in the loft.
Whether the loft is boarded for storage (raised boarding adds cost).
Access, roof shape, and whether there are rooms in the roof.
Damp or ventilation issues that need addressing first.

Grants and funding: ECO4 and the Great British Insulation Scheme

Some households can have insulation part- or fully funded through the Energy Company Obligation (ECO4) or the Great British Insulation Scheme. Eligibility depends on income, benefits, council tax band and the home's EPC rating. See our eligibility guide and the official gov.uk pages.

Eligibility guide

Sources

This page is general information, not advice, a valuation or a survey. Figures are indicative ranges from the named public sources; check the official source before making a decision.

Related guides

See the picture in a real area

Every area page shows the local energy-band distribution and what the register estimates insulation could save.

All areas by leakiness