Spray Foam Insulation Cost Calculator Written by Josh Jackman Updated on 26 January 2023 Spray foam insulation costs £20 to £50 per square metre. But how much it costs for you will depend on your house.Fortunately, we've got you covered with our spray foam insulation cost calculator.This useful tool instantly provides you with the average cost for your installation – whether you want to buy spray foam insulation for your loft, roof, or walls.Just enter the number of square metres or places in your home you want insulated, and our calculator will immediately give you a price. Get free spray foam insulation quotes Answer a few quick questions, and our trusted installers will send you bespoke spray foam insulation quotes – for free. Compare now Written by: Josh Jackman Lead Writer Josh has written about eco-friendly home improvements and climate change for the past four years. His work has been displayed on the front page of the Financial Times, he's been interviewed by BBC One's Rip-Off Britain, and he regularly features in The Telegraph and on BBC Radio.