Internal Wall Insulation
Around a third of the heat leaving an uninsulated home escapes straight through the walls. For solid-wall properties (typically built pre-1920) Internal Wall Insulation is the most effective fix - using SWIP-approved IWI board systems to lock warmth inside without changing the exterior.
What is Internal Wall Insulation?
Internal Wall Insulation (IWI) is a high-performance insulation board fixed to the inside face of your external walls and finished with plaster ready for decoration. Our installers use SWIP (Solid Wall Insulation Partnership) certified materials - the UK benchmark for quality, moisture management and long-term performance.
Why Uninsulated Walls Cost You Money
Solid brick and stone walls have no cavity to trap heat, so on a cold day you can lose as much as 35% of your heating energy directly through the wall fabric. That's money out of the window every time the boiler fires. IWI creates a thermal break between the cold wall and your room, dramatically reducing heat loss, eliminating cold surfaces and cutting the condensation and mould that come with them.
The Benefits
Stops Up to 35% Heat Loss
Insulated walls mean your heating system isn't fighting the weather. Your home warms faster and holds temperature for longer.
Warmer, Drier Rooms
By raising the internal surface temperature of the wall, IWI eliminates cold spots and the mould and condensation that follow them.
Certified SWIP Systems
We only install SWIP-approved IWI systems - the UK quality mark for solid wall insulation - with full insurance-backed guarantees.
Why Choose JMS Eco?
JMS Eco is a PAS 2030 compliant installer using SWIP IWI materials across the Wirral and Northwest. We survey every property for damp, ventilation and thermal performance before work starts - so you get a system that lasts, not one that traps moisture.
4 Easy Steps to Apply for a Grant
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