In order to get the 'best of both worlds' so to speak, External and Internal Insulation can be combined in one property – known as Hybrid Wall Insulation, or HWI. 

Hybrid Wall Insulation is best suited to properties in conservation areas, areas of significant aesthetic value, limited access to external elevations or where the outside of your property cannot be changed. This can be especially relevant if you live in Victorian or Georgian terraced housing.


Combining both internal and external wall insulation can provide the ideal solution to best insulate your home.

Internal Wall Insulation is installed on the street facing walls, with External Wall Insulation on the rest of the property. Hybrid Wall Insulation systems minimise loss of internal space, while keeping the original architectural features of the property.


The front of the property will still look the same, but will have an improved thermal performance. The rest of the property will be finished with a high quality render, which is available in various colours and finishes.

Perks of IWI

  • Increasing the monetary value of your home

  • Solving problems with your existing render

  • Low maintenance system

  • Offers total weather protection; virtually eliminates condensation and removes the chilly, damp atmosphere

  • Warmer house in winter and cooler house in summer

  • Maximises the benefits of both systems

  • Maintain the original architectural features of the property so that it is in-keeping with the rest of the row

Different types of Insulation

There are a number of different types of insulation that can be used for External Wall Insulation. Not all materials perform the same. For example, numerous other installers will offer expanded polystyrene boards to insulate your walls but they do not perform as well as other materials at insulating your home. 

Our Top Choice - Kingspan Phenolic Foam

Kingspan Phenolic Foam has excellent thermal performance comparatively to other products.

Phenolic foam also offers exceptional high vapour permeability, helping reduce condensation and prevent mould from forming.

Using a material with high degree of vapour permeability ensures your house can breathe.

The key factors you need to take into account for each type of insulation are:


  • Fire rating

  • Thermal performance (how well it insulates relative to its thickness)

  • Durability

  • Biodegradability and environmental impact

  • Moisture resistance

  • The breath-ability or vapour permeability (particularly for solid walls)

Considerations with EWI

  • Brick houses will need a simulated brick facing if rendering is not appropriate

  • It needs a specialist to design the system and install it properly - we can assist you with this

  • It must be correctly fixed so that it does not bridge the Damp Proof Course or crack

  • Rising damp must be rectified before fixing the insulation so that damp is not trapped inside

  • Reduction in internal floor space due to the internal insulation

If you are interested, please don't hesitate and CONTACT US now to arrange a free consultation with a member of our team of experts.