We turn cold, drafty houses into warm, cozy homes
Compare verified and approved insulation systems, access SEAI grants up to €8,000, and find NSAI-certified installers near you.
Join 1,700+ homeowners across Ireland who found trusted insulation installers with ISOTHERM
Free service • No obligation • Verified installers
✔ Verified NSAI Contractor • Free Survey Scheduled
What is Isotherm?
We are Ireland's authority on home insulation and retrofitting, built to bring clarity and trust to the home energy upgrade process.
A Directory of Trusted Installers
Isotherm is Ireland's leading directory connecting homeowners with certified and vetted insulation, ICF, and retrofit professionals.
An Unbiased Comparison Platform
We provide clear, expert guides on different insulation systems and construction methods, empowering you to make informed decisions.
A Hub of Expert Knowledge
Our blog and guides demystify the home energy upgrade process, from understanding SEAI grants to choosing the right materials.
Tailored retrofitting solutions built for Ireland
Whether you are a homeowner seeking to lower heating bills or a certified contractor looking to list your business, we connect you with vetted reliability.
For Homeowners
Maximize SEAI Grants (Up to €8,000)
Improve your BER rating, lower energy bills, and cut heat loss. Learn about government grants for attic, cavity wall, floor, and external wall insulation.
Check Grant EligibilityFind Vetted & Approved Contractors
Never hire unverified installers. Browse our database of fully-insured, NSAI-registered, and SEAI-approved insulation partners near you.
Browse Registered InstallersInsulation & Retrofit Tech Guides
Building new or doing a deep energy retrofit? Discover modern Insulation standards, Cavity upgrades, Attic solutions, and ICF building systems.
Compare Insulation TypesFor Retrofit Installers
Generate High-Intent Retrofit Leads
Connect directly with Irish homeowners searching for certified energy upgrades in your county. Receive vetted jobs with property metrics.
Register Your BusinessHighlight Your Quality Vetting
Build immediate trust with a verified company profile. Showcase reviews, project portfolios, SEAI registration, and NSAI certificates.
List as Certified PartnerCustomer Support & Regulations
Ensure compliance with modern building regulations and safety documentation standards. Access specialized installers partner support.
Access Contractor SupportHow Isotherm Works
Finding the right installer is as easy as 1, 2, 3.
Search
Use our directory to find installers by location and speciality.
Compare
Review profiles, project galleries, and homeowner reviews.
Connect
Contact installers directly for a no-obligation quote.
Compare Insulation Types
Expertly structured comparison guides to find the best thermal efficiency upgrades for your building.

External Insulation
Learn MoreAttic Insulation
Learn MoreInternal Insulation
Learn MoreFloor Insulation
Learn MoreCheck Your SEAI Grant Eligibility
The Irish government offers generous grants of up to €8,000 to make your home warmer and more energy-efficient. Let us guide you through the process.
Check Grant EligibilityDon't Ruin Your Renovation: NSAI Quality Standards
Substandard retrofitting damages properties and poses serious safety risks. Learn how to protect your home and ensure your insulation project meets official standards.
Ventilation & Airflow Safety
Substandard insulation work can block attic soffits and fascia vents. Restricting airflow causes condensation, mold, and risks hazardous carbon monoxide buildup.
Utility & Gas Box Relocation
Gas meter boxes must be moved to the exterior of the finished external insulation surface. Trapping utility boxes behind insulation risks gas leaks building up behind EWI boards.
NSAI Certified Products
There is no legal requirement in Ireland for insulation installers to be NSAI certified. Homeowners must independently verify contractor certification.
NSAI Recommended 6-Step Homeowner Checklist
Check that the contractor is an NSAI registered installer.
Verify all products (Cavity Wall / External systems) are NSAI certified.
Confirm the contractor has active, comprehensive liability insurance.
Verify active SEAI registration to guarantee grant eligibility.
Ask for client references and visit completed insulation projects.
Read the warranty small print — installation must match manufacturer guidelines.
Why Homeowners Trust Isotherm
Verified Installers
Every installer is vetted for insurance, certification, and quality of work.
Grant Support
We guide you through the SEAI grant application process to maximize your savings.
Compare Options Easily
Browse installer profiles, project galleries, and insulation systems all in one place.
100% Free Service
Our platform is completely free for homeowners. No fees, no commission.
Only Trusted and Verified Installers
Every professional in our network is fully accredited, insured, and verified to execute high-quality retrofits.
What Irish Homeowners Say
Hear from home energy upgrade participants who successfully retrofitted their properties.
"Isotherm helped me find the right installer and saved me thousands. My home has never been warmer!"
"The whole process was so simple. I compared three quotes and picked an amazing local company. Highly recommended."
"We were clueless about SEAI grants. Isotherm made it easy to understand and now our heating bills are a fraction of what they were."
Find Trusted Insulation Installers Near You
Free service. No obligation.