Do I have to use one of these companies to get the grant?

Yes. SEAI only pays a grant on work done by a company on its register, and the company claims it on your behalf. Work done by anyone else is not covered, however good it is.

How many quotes should I get in Dublin?

Three, from companies registered for the same job, and ask each for a written breakdown. Quotes for the same house often differ by thousands because they include different work, not because one is dearer.

Is this list in any order of merit?

No. Companies based in Dublin come first, then the ones that travel to it, then One Stop Shops, then alphabetical. Being on the register means the paperwork is in order, not that the work is good.

Cavity wall insulation installers in Dublin

81 companies on the SEAI register are based in or serve Dublin for cavity wall insulation (register as of 8 September 2026).

Insulation boards fixed to the outside walls of a terrace mid-job, meter boxes hanging clear of the wall. — Garrick Close, Kingston upon Hull: bungalow renovations, November 2023 · Hullian111 · CC BY-SA 4.0 · Photo credits

Based in Dublin

9 of them. Sorted by what they are registered for, then by name — this is not an order of merit.

Bord Gais Energy LtdOne Stop Shop
Attic insulationCavity wall insulationExternal wall insulationHeat pumpHeating controlsInternal wall insulationSolar hot waterSolar panelWindow and door
Nationwide · SEAI no. 14183 · Website
Based in Dublin.
House 2 Home Retrofit LtdOne Stop Shop
Attic insulationCavity wall insulationExternal wall insulationHeat pumpHeating controlsInternal wall insulationSolar hot waterWindow and door
Nationwide · SEAI no. 15918 · Website
Based in Dublin.
Lough ProjectsOne Stop Shop
Attic insulationCavity wall insulationExternal wall insulationHeat pumpHeating controlsInternal wall insulationSolar hot waterWindow and door
Based in Dublin · serves Dublin and Leinster · SEAI no. 17674 · Website
Based in Dublin.
Moston Construction LtdOne Stop Shop
Attic insulationCavity wall insulationExternal wall insulationHeat pumpHeating controlsInternal wall insulationSolar hot waterWindow and door
Nationwide · SEAI no. 16068 · Website
Based in Dublin.
Complete Insulations and Energy Upgrades Ltd
Attic insulationCavity wall insulationExternal wall insulationHeating controlsInternal wall insulation
Based in Dublin · serves Dublin and Leinster · SEAI no. 12529
Based in Dublin.
Innovate Insulation Ltd
Attic insulationCavity wall insulationInternal wall insulation
Nationwide · SEAI no. 17635
Based in Dublin.
National Retrofit & Construction Services Ltd
Attic insulationCavity wall insulationExternal wall insulation
Nationwide · SEAI no. 16122
Based in Dublin.
Powell Insulations Ltd
Attic insulationCavity wall insulationInternal wall insulation
Based in Dublin · serves Dublin and Leinster · SEAI no. 10606
Based in Dublin.
Solid Build Construction
Attic insulationCavity wall insulationInternal wall insulation
Based in Dublin · SEAI no. 17636
Based in Dublin.

Also cover Dublin from elsewhere (72)

These told SEAI they cover the province Dublin is in, or listed it among the counties they serve. Ask how far they travel before you go any further. Names only here; each one's full register row is on its own county page. OSS = One Stop Shop.

Activ8 Energies (OSS) · Ashgrove Engineering Ltd T/A Ashgrove Renewables (OSS) · Aspen Eco Power (OSS) · Bayview Contracts Ltd (OSS) · Breffni Insulation Ltd (OSS) · Churchfield Home Services (OSS) · Cooper Insulation Ltd. (OSS) · Electric Ireland Superhomes (OSS) · Energlaze Home Energy Upgrades (OSS) · Energyfix (OSS) · Envirobead Ltd. (OSS) · Greenwatt Ltd (OSS) · Home Comfort Retrofits Ltd (OSS) · Integrate Home Energy Upgrades Limited (OSS) · Kilgobbin Castle Holdings Ltd t/a Insulex (OSS) · Kingdom Installation Ltd (OSS) · Kingspan Insulation Ltd (OSS) · Kore Retrofit Ltd (OSS) · Larkrock (OSS) · Munster External Wall Insulation T/A SE Systems (OSS) · OHK Energy LTD (OSS) · Retrofit Design Ltd (OSS) · Retrofit Energy Ireland (OSS) · SSE Airtricity Energy Services Ltd (OSS) · WiEnergy (OSS) · Absolute Insulation Ltd · All In Insulation · Alpha Insulation Ltd T/A Western Insulation · Anthony Coughlan Heating & Plumbing TA C&S Construction Services · Ardvark Insulation Ltd · C.D.M. Contracts Ltd · CK Energy Management Solutions (EMS) Ltd t/a ENCON · Clane Building Works · Clar ICH Ltd · Corkery Alu-Cast Enterprises Ltd · Damien Ryan Contracts Ltd · Derchil Limited t/a CosiHomes · Eamonn Finn · Eco Home Insulation · Ecotec Insulation Ltd · Ecotech Contracts IRI Ltd · Ecowise Insulation Ltd · Eirgreen · Evertherm Ltd T/A Annalee Energy Ltd · Fagan Crossmolina Limited · Finlay EcoFit Tullamore Ltd · Gallen Insulation Ltd · Gar Insulation Ltd · Harrington Insulations Limited · Home Works Insulation · Hometherm Insulation Ltd · Instant Eco Homes Ltd · Jacob Insulation Limited · Keating Insulation Ltd · Kelly Insulation Heating & Plumbing · Kingscourt Insulation Ltd · Leetherm Insulation Ltd. · Leitrim Warmer Homes CLG · McCormack Insulation · Meegan Insulations · Metro Insulation Ltd · Moran Retrofit Solutions · NE Energy Efficient Homes Ltd · O Leary Insulation · Premier Insulations · Ryan Spray Foam · South East Insulations · Spreadwell Construction Ltd · Superior Insulations Ltd · Sustainable Warmth Ltd · Thermowise Insulations Limited · Tirconaill Contracts Ltd T/A Mc Taggart Insulation

What it costs, and what the grant pays

The grant for a semi-detached house is €1,300. SEAI recorded a middle price of €1,550 for this work last year, which leaves about €250 for you to pay. These are national figures, not Dublin ones — SEAI does not publish prices by county.

What it costs on a home like yours, and what you are left paying

Before you sign

Wait for your grant approval email before any work starts. SEAI does not pay for work that began before it was approved.
Get at least three quotes, and check each one covers the same job — the cheapest quote is often the one that leaves something out.
Check the company is on the register on the day you sign. Companies join and leave it, and this page is a copy taken on one day.
Get it in writing: what is being done, what it costs, when it starts and when it is finished.

How the application works

Ask up to five of them

Fill in one form, tick who you want to hear from, and we pass your details to those companies and nobody else. It costs nothing and you are under no obligation.

Get cavity wall insulation quotes in Dublin

Common questions

Do I have to use one of these companies to get the grant?: Yes. SEAI only pays a grant on work done by a company on its register, and the company claims it on your behalf. Work done by anyone else is not covered, however good it is.
How many quotes should I get in Dublin?: Three, from companies registered for the same job, and ask each for a written breakdown. Quotes for the same house often differ by thousands because they include different work, not because one is dearer.
Is this list in any order of merit?: No. Companies based in Dublin come first, then the ones that travel to it, then One Stop Shops, then alphabetical. Being on the register means the paperwork is in order, not that the work is good.

Other work in Dublin

Listed on SEAI’s public registers on 8 September 2026. Being registered is not an endorsement by SEAI or by us. Check the current register on seai.ie before you sign anything. Not affiliated with SEAI.