Warmshell Internal Insulation

Warmshell internal insulation is a highly breathable IWI (Internal Wall Insulation) system that is fitted to the inside of walls and roofs.

It comprises of just three components:

  1. Natural wood fibre insulation boards
  2. Specialist fixings
  3. Traditional lime plaster

Warmshell interior internal wall insulation systems are a practical solution when fitting insulation to the outside of property isn’t an option. That could be because you can’t get access, you don’t own the whole property, or you can’t change the look of the building, for example if you live in a conservation area or your home is part of a terrace.

Also, with Warmshell interior internal insulation, there is no need to hire scaffolding, negotiate access with neighbours, think about external finishes, or get planning permission – because everything’s done inside your home.


Ideal for hard-to-heat homes

You can use Warmshell interior internal insulation in almost any situation. However, it’s particularly well-suited to historic, hard-to-heat homes – irrespective of whether they are brick, masonry or timber frame.

In these situations, the breathability of Warmshell, and its ability to buffer and control moisture, is particularly helpful.

Easy to install

Installing Warmshell internal insulation in the interior of your home is surprisingly straightforward.

It is well within the reach of a capable DIYer, and should be second nature to most builders. It is also much easier and more comfortable than using mineral wool alternatives.

All you need to do is follow a simple, five-step process:

  1. Move furniture and furnishings so that your exterior-facing walls can be accessed (internal walls aren’t affected)
  1. Scour the wall with a coat of Lime Green Duro lime render base coat to ensure a completely level surface
  1. Cut the Warmshell insulation boards to size and aim to cover as much as the wall surface as possible (cables for sockets and light switches may need to be extended through the insulation, though this isn’t always necessary)
  1. Secure the Warmshell insulation boards to the wall surface using WT hammer-in fixings or WTS screw-in fixings depending on nature of the wall (existing lime plaster can be left in place)
  1. Plaster over the Warmshell insulation boards with two-passes of our one coat lime plaster Lime Green Solo, to achieve an 8-to-10mm covering.

(Optional) To achieve added fire resistance and retain breathability, paint the wall with one of our Lime Green mineral paints (or other breathable paints such as limewash or Aglaia).

Watch how easy it is to install

Warmshell Interior Documents

We are here to support you throughout the installation process. Download our installation guide. And, if you ever want more advice and guidance, give us a call.

We are here to support you throughout the installation process.

See all our guides

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To help you on your way, we also offer training, and can put you in touch with a wide network of system-trained installers.

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