Eco Surface Solutions

Internal Cork Wall Insulation

45% air-permeability reduction in pre-1919 Edinburgh end terrace

Wheatley Group needed to make a cold, uninsulated pre-1919 end terrace comfortable for tenants — without losing valuable internal space. Just 6 mm of SprayCork plus a 2 mm plaster skim delivered a 45% reduction in air permeability, independently tested by RTRFIT.

45% air-permeability reduction in pre-1919 Edinburgh end terrace — Wardie Square, Edinburgh
Location
Wardie Square, Edinburgh
Property
Pre-1919 solid-brick end terrace · social housing
Area
Internal exterior-facing walls
Duration
3 days
Completed
May 2025

The challenge

A pre-1919 solid-brick end terrace with no insulation, sloped ceilings, uneven walls, small nooks and very tight room sizes. The property was cold, with high moisture and damp/mould risk. Traditional internal wall insulation would have reduced room sizes and risked trapping moisture behind the system.

Our solution

CorkSol SprayCork applied at just 6 mm thickness, finished with a 2 mm plaster skim. Because the product is spray-applied directly to the wall, there is no cavity behind it for moisture to build up in. RTRFIT carried out independent Pulse air-permeability testing before (April 2025) and after (May 2025).

Learn about Internal Cork Wall Insulation →

Results

  • Air permeability reduced from 15.14 to 8.44 m³/m²h @50Pa — a 45% reduction
  • No loss of room size — total build-up just 8 mm including plaster skim
  • Breathable system suited to traditional solid-brick construction
  • Independently verified by RTRFIT with no other measures in place

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