Thin wall insulation is an internal insulation system designed specifically for properties where standard insulation methods — such as thick thermal plasterboard or external wall insulation — are either impractical, too disruptive, or would result in an unacceptable loss of room space. It uses advanced, ultra-slim insulation materials that are applied directly to the inside surface of cold external walls.
Standard thermal plasterboard (PIR-backed) adds 50 to 100mm to the wall thickness, which can make small rooms feel cramped and requires moving skirting boards, architraves, sockets, and switches. Thin wall insulation products like Iso-Therm, Wallrock Thermal Liner, and Spacetherm Aerogel achieve a meaningful improvement in wall temperature at a fraction of the thickness — typically just 3mm to 10mm.
While thin wall insulation won't achieve the same U-value improvement as thicker systems, it is highly effective at raising the internal wall surface temperature above the dew point — which is the critical threshold at which condensation forms. For many properties across Suffolk, Norfolk, and Essex, this is exactly what is needed to solve persistent condensation and black mould problems on cold external walls.
