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Clarcon installs external wall insulation across Dublin, wrapping older and solid-wall homes in a continuous layer of insulation and a fresh weather-resistant finish. The result is a warmer home, lower heating bills and an exterior that looks renewed.
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External wall insulation, often called EWI or house wrapping, is a layer of insulation fixed to the outside of your home’s walls. Insulation boards are fixed to the wall, covered with a reinforced mesh and basecoat, then finished with a weather-resistant render.
It is the right solution for homes where cavity wall insulation is not an option. Many Dublin homes built before the 1930s have solid walls, and a large number of later homes are hollow block. These walls cannot be filled the way a cavity wall can, so insulating from the outside is the practical answer.
Uninsulated walls are one of the biggest sources of heat loss in an older home. Insulating them externally keeps the warmth in, protects the structure from the weather, and does not cost you any internal room space. Insulating the wall externally also reduces thermal bridging, the cold paths where heat escapes through the structure, and improves the wall’s U-value, the measure of how well it holds heat.
Walls are a major route for heat to escape an older home. Insulating them externally reduces that loss and brings your heating costs down.
EWI removes cold spots and draughts and keeps room temperatures more even throughout the year.
Warmer internal wall surfaces reduce the condensation that leads to damp and mould in older properties
External wall insulation is one of the highest-impact energy upgrades, which improves your Building Energy Rating.
The render finish gives tired or weathered walls a clean, modern look, so the upgrade improves how the house looks as well as how it performs.
A well-installed EWI system has a lifespan of 30 years or more.
Here is how we take an external wall insulation project from survey to finished render.
We assess the property, the wall type and the condition of the existing surface, and talk through the finish you want.
We agree on the insulation system, the thickness and the render finish, including colour and texture, so the result suits your home.
We fix the insulation boards, apply the reinforced basecoat and mesh, and finish with the weather-resistant render. Window and door reveals are detailed properly.
We inspect the finished work and hand over a home that is warmer, better protected and visibly renewed.
To be eligible for an SEAI external wall insulation grant:
Insulating more than 25 percent of your home’s surface area can trigger additional Building Regulations requirements. And since March 2026, homeowners who previously received a grant for cavity or internal wall insulation may be able to apply for a second wall insulation measure.
Grant amounts and rules are set by SEAI and can change, so always confirm the current details on the SEAI website before you plan your budget.
| Item | Typical Range | What Moves The Price |
|---|---|---|
| External wall insulation | €60 – €100 per m² | Insulation type and thickness, render finish |
| Standard 3-bed semi-detached house | €8,000 – €15,000 total | Property size, wall area, detailing |
The insulation material affects the cost. Common options are expanded polystyrene (EPS), mineral wool and phenolic board, each with different performance and price. The render finish also plays a part, with marble chip and textured finishes costing more than a standard acrylic finish.
Where an SEAI grant applies, it covers a meaningful share of the cost, so the figure you pay can be considerably lower than the totals above. See the grants section for current amounts, and our guide to external wall insulation costs in Dublin for a fuller breakdown.
Clarcon has worked on building and renovation projects across Dublin for over 17 years. External wall insulation is detailed work, the quality of the installation decides how well the system performs and how long it lasts, and experience matters.
We are clear about cost and process from the start. You get a detailed quote and honest guidance on the system and finish that suits your home.
And we deliver to a programme. One point of contact, an agreed timeline, and a finish you will be glad to look at. If your home needs wider modernising as well as insulation, we also carry out full house renovations.
House extensions in Dublin typically cost €1,900 to €2,500 per square metre for a standard single-storey rear extension, rising to €3,000 for a high-spec finish. A 30 square metre rear extension usually lands between €70,000 and €95,000 all-in, including VAT and professional fees.
Many rear extensions are exempt from planning permission if they are 40 square metres or less and meet the conditions. Side extensions, two-storey extensions and larger builds usually need permission. We confirm exactly where your project stands at the design stage.
A rear extension is generally exempt up to 40 square metres, provided at least 25 square metres of garden space remains, and the extension is not higher than the existing house. Two-storey extensions have much smaller exemption limits.
A single-storey extension usually takes around 10 to 12 weeks of construction, depending on size and complexity. Two-storey and wrap-around extensions take longer. Planning permission, if needed, adds time before construction starts.
A well-built extension generally adds value, particularly extensions that create an open-plan kitchen and living space. The return depends on the quality of the build and the local market, so it is worth getting advice before you commit.
Beyond the build cost, budget €5,000 to €10,000 for professional fees. This covers architect or architectural technologist drawings, structural engineering and the BER assessment required after the build.
A two-storey extension gives the most space for your money per square metre, but needs planning permission and more structural work. A single-storey rear extension is simpler and often exempt. The right choice depends on the space you need and your site.
Yes. If your extension needs planning permission, we manage the application as part of the project, working with the drawings and design, so the process is handled for you.
Yes. Exemption from planning permission does not exempt an extension from Building Regulations. The build must still comply with rules on structure, insulation, fire safety and more.
The single-storey rear kitchen extension is the most common. Most homeowners are looking to create an open-plan kitchen, dining and living space at the back of the house.
Yes. Dublin has a large stock of older homes, and we have extended many. Period and protected properties need more careful planning, and any work to a protected structure requires planning permission.
That depends on what you need the space for, your site and your budget. A larger extension is not always better. We give honest advice on the size that suits your home rather than the biggest one possible.
