Roofing

How Much Does It Cost to Install Roof Insulation?

£300 – £1,800

depending on type

Roof insulation costs between £300 and £1,800 depending on the type of insulation, the loft area, and whether it is a cold loft (insulation laid at ceiling joist level) or a warm loft conversion (insulation fitted between the rafters). Proper loft insulation can save £150-£300 per year on energy bills and is one of the most cost-effective home improvements available.

Average cost

£300 – £1,800

depending on type

Prices vary by region, property type and tradesperson. Always get at least two quotes.

What affects the price?

Insulation type - mineral wool roll at ceiling level costs £300-£600 for a standard semi; rigid PIR board between rafters costs £800-£1,800

Loft access and condition - a clear, accessible loft is quick to insulate; a loft with no boards, limited headroom, or existing insulation to remove takes longer

Depth of insulation - Building Regulations recommend 270mm of mineral wool; doubling up existing thin insulation is a quick, cheap improvement

Spray foam - spray foam insulation is fast to apply but can cause problems with mortgage valuations and is generally not recommended

Labour vs materials

Labour for laying loft insulation roll in an accessible loft takes one day for a team of two. Labour accounts for roughly 40-50% of the total cost; insulation materials make up the remainder.

Questions to ask your tradesperson

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