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 Sligo?

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 Sligo 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.

External wall insulation installers in Sligo

105 companies on the SEAI register are based in or serve Sligo for external wall insulation (register as of 8 September 2026).

A terrace of single-storey homes under scaffolding and pink debris netting, the roof stripped back. — Garrick Close, Kingston upon Hull: bungalow renovations, September 2023 · Hullian111 · CC BY-SA 4.0 · Photo credits

Based in Sligo

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

Brusna Energy Solutions Ltd
Attic insulationCavity wall insulationExternal wall insulationHeat pumpHeating controlsInternal wall insulationSolar hot waterWindow and door
Based in Sligo · serves Connacht · SEAI no. 10066
Based in Sligo.
CJH Construction
External wall insulationInternal wall insulation
Based in Sligo · serves Dublin, Leinster and Connacht · SEAI no. 18064
Based in Sligo.
John Doohan and Company Ltd
Attic insulationCavity wall insulationExternal wall insulationInternal wall insulation
Based in Sligo · serves Connacht · SEAI no. 15884
Based in Sligo.
Pentico Contracting Ltd
External wall insulation
Based in Sligo · serves Connacht · SEAI no. 18203
Based in Sligo.

Also cover Sligo from elsewhere (101)

These told SEAI they cover the province Sligo 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.

Ashgrove Engineering Ltd T/A Ashgrove Renewables (OSS) · Bayview Contracts Ltd (OSS) · Bord Gais Energy Ltd (OSS) · Breffni Insulation Ltd (OSS) · Churchfield Home Services (OSS) · Cooper Insulation Ltd. (OSS) · Electric Ireland Superhomes (OSS) · Envirobead Ltd. (OSS) · Greenwatt Ltd (OSS) · House 2 Home Retrofit Ltd (OSS) · Kingdom Installation Ltd (OSS) · Kingspan Insulation Ltd (OSS) · Kore Retrofit Ltd (OSS) · Moston Construction Ltd (OSS) · OHK Energy LTD (OSS) · Retrofit Design Ltd (OSS) · Retrofit Energy Ireland (OSS) · SSE Airtricity Energy Services Ltd (OSS) · Absolute Acrylics Ltd · Algricris Construction Ltd · Anthony Coughlan Heating & Plumbing TA C&S Construction Services · AP Building Contractors Ltd · Ap Eco Building & Renovation · AR Plastering Ltd · Ballinderry Developments Ltd T/A Rebuild · Century Retrofit Ltd · Ciocan Construction Ltd · Connacht/Galway External Insulation Ltd · Cornacloy Construction Ltd · Costello Insulation LTD · CW Xterior Solutions Ltd · Damien Ryan Contracts Ltd · David Flaherty Construction LTD · DC Energy Solutions · Decarb Contracts Ltd · Declan Fahy Plastering LTD · Derchil Limited t/a CosiHomes · DMT Renewables Ltd · Dromahair Tully Construction Ltd · Ds Fallon · Dublin All Trades Building Services · Duey Brothers Ltd · Eco Pro Insulation · Eco Smart External Insulation Ltd · Eco Thermal Homes · Ecowrap · Energy Retrofit Ireland · External Insulation Plastering Ltd · Finlay EcoFit Tullamore Ltd · Floelen Construction Ltd · G.V.Services Limited · Gmg Contracts Ltd · Grainger Energy Solutions Ltd · Green - Lux Construction Ltd · Green Air Technologies Ltd · Hamkel Holdings Ltd / Soltherm · Harrington Insulations Limited · Home Building Solutions T/A HBS Elegant build Ltd · Homergy Ltd T/AComfort Solutions Retrofit · Inline Construction and Custom Carpentry Ltd · Insulate Ireland · Jacob Insulation Limited · Johnathan Timoney T/A Rendpro Ltd · Kilmallock Developments Ltd · Kilsarn Warmer Homes · Leitrim Warmer Homes CLG · Madden Developments Ltd · Marcus Turner · McCaher Construction Ltd. · McMorrow Renewables Limited · Metro Insulation Ltd · Moran Retrofit Solutions · MS Plastering Contractor · National Retrofit & Construction Services Ltd · Novin Consultants Ltd · Nrr Renovations Limited · OCI Insulation · Pa Home Renovations · Paddy Kilduff and Sons Builders Ltd TA Kilduff Con · Peter Brereton Plastering · Philip Reynolds · Proconstruct Limited · Professional Solid Insulation · Raphael Considine Construction · Raphael Murray Plastering & EWI · Rend Master Ltd · RMC Ecobuild Ltd · Rmn Developments Ltd · SBN Solid Home Ltd · Sean Paul Construction Ltd · Solaregy T/A Sola · Solid Insulation Systems Ireland Ltd · Sovereign Finishes Limited · Spreadwell Construction Ltd · Steve Moylan Limited · Superior Insulations Ltd · Tirconaill Contracts Ltd T/A Mc Taggart Insulation · TLI Group Ltd T/A Transmission Links Ireland Ltd · Tomasz Rulak T/A Tombet Building · Walter Moran Insulation · Winters Construction

What it costs, and what the grant pays

The grant for a semi-detached house is €6,000. SEAI recorded a middle price of €23,247 for this work last year, which leaves about €17,247 for you to pay. These are national figures, not Sligo 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 external wall insulation quotes in Sligo

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 Sligo?: 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 Sligo 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 Sligo

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.