White & graphite EPS
A common domestic option with a practical balance of insulation value, thickness and cost.
External Wall Insulation
Complete EWI systems for existing homes
EPS, mineral wool, XPS, phenolic and wood-fibre insulation, specified to suit the property and finished with a compatible render system.
Choosing the insulation
Different walls need different materials
The insulation board is only one part of the system. The right choice depends on the existing wall, required thickness, exposure, detailing around openings and the finish you want. We do not use the same specification on every house.
- Wall construction and condition assessed before specification
- Thickness and reveal depth considered together
- Plinths, sills, roof lines and external pipework included in the discussion
- Compatible adhesive, fixings, reinforcement, primer and finish
Insulation options
The board is selected for the property
Each material has strengths and limitations. The aim is not to use the most fashionable board, but the one that makes sense for the wall and the required build-up.
Mineral wool
A vapour-open, non-combustible option for systems where those characteristics are required.
XPS
Used around plinths and other areas where resistance to moisture and impact is important.
Phenolic boards
Products such as Kingspan K5 can reduce the required thickness where space around details is limited.
Wood fibre
A suitable option for certain breathable wall constructions and compatible render systems.
A complete build-up
Every layer has to work with the next one.
System build-up
What happens before the final render
Prepare the wall
Loose material is removed and repairs, protection and starter details are agreed.
Fit and fix the insulation
Boards are bonded, mechanically fixed and kept tight with staggered joints.
Reinforce the surface
Beads, stress patches, mesh and basecoat form the reinforced layer.
Prime and finish
The specified primer and render complete the system once the background is ready.
Details clients notice later
Openings, plinths and junctions matter
These are the places where poor planning becomes obvious. They are discussed before the wall is covered, not improvised at the end.
Planning EWI?
Send the elevations and postcode
Clear photographs help us discuss likely insulation options, access and the details that may affect the build-up.