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Thin internal wall insulation
Philippa Lewis 20/07/2026 - 1.52 PM
I am interested in retrofitting thin internal wall insulation (e.g. ISO-therm) in a ground floor flat, which has solid walls and is currently not well insulated. I understand TIWI is applied directly on top of existing plaster (assuming plaster is dry and in reasonable condition) with an adhesive - then skimmed over the top. Hoping for some suggestions on how to find an approved/experienced TIWI fitter - and at a more basic level - if this would generally be an 'insulation' or a 'plastering' category of job. Thank you
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2 Answers
Space Solution Interiors Ltd
Rating: 4.5 out of 5
Hello
You would need to install at least a 50mm insulation to be able to obtain a better EPC rating, a lot of plasters will install it but not all.
Answered13 July 2026
1
Trident Damp Solutions
Rating: 3.8 out of 5
Hi Philippa we install a lot of ISO-THERM and are approved installers the product either goes directly to the substrate with an adhesive or to a stud wall which would then be re skimmed afterwards
Answered20 July 2026
1