Internal Wall Insulation
What is it?
How does it work?
IWI protects your home from heat loss on the inside, and is usually installed on walls that face the outside elements. So, for example, for a mid-terrace house, you wouldn’t need to insulate the walls between your home and your neighbours.
This type of insulation slows down the transfer of heat, keeping it inside, for longer.
How is it installed?
IWI is achieved by attaching thermally engineered insulation material to the interior walls of your property and finishing off with skim plasterboard for a smooth and sleek finish, ready for decorating.
As illustrated below, you can see just how this is done. The existing external wall and plaster are prepared with thermally engineered SWIP Stud extruded polystyrene, which is bonded to a 15mm strip of Orientated Strand Board, before an Earthwool SWIP Batt water-repellent glass mineral wool slab is placed on top. Next, the SWIP vapour control layer (VCL) is formed and sealed, completed by a 12.5mm skim plasterboard.

We work with our UK-based supplier SWIP IWI, who is fully accredited by the British Board of Agrément (BBA), using high-performance, water repellent glass mineral wool insulation, manufactured with ECOSEÒ Technology.

Internal Wall Insulation is an efficient and easy way of insulating solid walls to keep your home warm and cosy, and can also significantly help you cut down on your energy bills and CO2 emissions each year.
What are the benefits of Internal Wall Insulation?
Energy efficiency
Appearance
Insulating inside can boost the overall interior décor of your home. It also has little impact on the outside appearance of your property, so you can retain the external look and feel of your current home without any fuss.
Comfort
Environment
Alternative
Minimal disruption
Satisfaction achieved
Years of combined experience
Projects completed
Other considerations
If there are any penetrating damp issues, these must be addressed before any IWI takes place to avoid any further issues in the future.
When installing fixtures and fittings on IWI, such as artwork, mirrors, shelves or dado rails, avoid damaging, puncturing or penetrating the vapour control layer (VCL) of the insulation and instead place them and their fixings directly over the SWIP stud. Seal any holes created by the removed fixings with SWIP Multi-Purpose Sealant.
