External wall insulation in Clare

How EWI works

Insulation boards are fixed to the outside of the existing walls, then covered with a base coat, a reinforcing mesh and a finishing render. Because the insulation is on the outside, the whole wall stays warm, cold bridges at floors and internal walls are reduced, and you keep every centimetre of floor space inside. It suits cavity block and solid block houses in particular, which make up a lot of the homes built in Clare from the 1960s to the 2000s.

The job, step by step

1. Survey and prep. We check the walls, fix cracks or damp, and take off downpipes, lights and anything fixed to the wall. Window sills are extended so water still runs clear of the thicker wall.
2. Insulation boards. Boards are bonded and mechanically fixed, butted tight with no gaps. Edges at windows and doors are sealed and beaded.
3. Base coat and mesh. A base coat goes over the boards with reinforcing mesh pressed in across the whole wall. This is what stops the render cracking. Corners get beads for straight, hard-wearing edges.
4. Finish. A primer and a siloxane render finish in the colour you pick. The colour runs through it, so it doesn't need painting, and rain runs off rather than soaking in.

NSAI Agrément-certified systems

An EWI system is more than boards and render. The insulation, adhesive, fixings, mesh, beads and finish are tested together as one system. In Ireland, systems are certified by the NSAI under its Agrément scheme, and the certificate sets out how the system must be installed. We install to the system's certificate and the manufacturer's details, rather than mixing and matching parts. We'll tell you which system we're proposing for your house so you can check it yourself.

Detailing at windows, doors and eaves

Most EWI problems show up at the edges, not in the middle of a wall. At windows and doors, the insulation is returned into the reveals where there's room, so the frame isn't left as a cold spot. Joints between boards and frames are sealed with expanding tape and beads so rain can't get behind the render. Sills are extended or replaced so water drips clear of the new wall face.

At the eaves, the insulation is run up as high as possible and closed off neatly under the soffit, without blocking roof ventilation. At ground level, a starter track sets the base line above the damp-proof course, and boards suited to wet conditions are used where the wall meets the ground. Gas meters, vents, pipes and lights are extended or refitted so they sit properly on the new surface.

Choosing a finish

Siloxane render comes in a wide range of colours and a few grain sizes, from a fine smooth texture to a coarser one that hides marks better. Darker colours absorb more heat, so we'll talk about which shades suit the system. Brick slips or other cladding can be used on part of a wall where you want a contrast.

Render-only option

If you don't need insulation, the same base coat, mesh and siloxane finish can go straight onto existing walls. It's a durable, low-maintenance render for tired or cracked walls.

Older stone houses

Solid stone walls need breathable materials. A standard EWI system isn't always the right answer on a stone cottage. See our lime render page for why.

Other services

• Lime render & plaster
• Natural slate roofing
• Extensions & new build
• Fabric-first retrofit
• Photo gallery