Cavity / Internal Wall Insulation
Insulation inside the wall build-up — boards in the cavity or behind the lining that quietly stop heat at the wall line.
One System, Built to Work Together.
Where facades can't change, the insulation goes inside: rigid boards in the cavity between leaves, or fixed to the inner face behind plasterboard and plaster.
EPS and XPS boards cut cleanly and fit tightly between wall ties and framing, upgrading thermal comfort room by room or across whole projects.
- Double-leaf cavity walls
- Internal retrofit behind linings
- Partition and party walls
- Basement and garage internal walls
- Cold-room and utility enclosures
Layer by Layer.
- 01
Outer Leaf
The external masonry skin that faces the weather.
- 02
Cavity Insulation
Rigid boards fill the cavity, fixed clear of mortar droppings and ties.
- 03
Inner Leaf
The internal structural skin of the wall.
- 04
Internal Finish
Plaster or lined finish completes the room side.
01Comfort Without Facade Works
Upgrade thermal performance with no scaffolding and no change to the elevation.
02Quieter Rooms
Insulated cavities damp airborne noise between outside and in.
03Condensation Control
Warm inner surfaces stop damp patches and mould at cold spots.
04Cut-to-Fit Simplicity
Boards trim with a blade and fit tight between ties, studs and services.
Common questions about this system.
Where is the Cavity / Internal Wall Insulation system used?
It is typically used for double-leaf cavity walls, internal retrofit behind linings, partition and party walls, basement and garage internal walls and cold-room and utility enclosures.
Which Insutech products are used for cavity / internal wall insulation?
The recommended system is built with EPS 14kg/m³, EPS 17kg/m³, EPS 20kg/m³ and Iso Foam — full details for each are on the recommended products cards on this page.
How is the system installed?
The system is installed in 4 stages: outer Leaf, cavity Insulation, inner Leaf and internal Finish. The system build-up section on this page illustrates the full sequence.
What are the main advantages of the cavity / internal wall insulation system?
The key advantages are comfort Without Facade Works, quieter Rooms and condensation Control — each is explained in the Key Benefits section on this page.