How can I check if my cavity wall or external insulation contractor and products are certified with the National Standards Authority of Ireland (NSAI)?

NSAI recommends the following six steps all homeowners should take before deciding on an insulation contractor:

  1. Check that the contractor is an NSAI registered installer. A full list is available on NSAI website, Registered Installers
  2. Check that ALL products used are certified by NSAI, on Cavity Wall / External Insulation
  3. Check that the contractor is fully insured.
  4. Check that the contractor is registered with Sustainable Energy Authority of Ireland (SEAI) for grant works. It is important that this registration is active; otherwise you could lose eligibility for your grant payment.
  5. Always ask for references and if possible, go see completed projects.
  6. Ask about warranties, verify and READ ALL SMALL PRINT.  Remember that no warranty will be honoured if the insulation system is not installed according to the manufacturer’s instructions.

You can find a list of NSAI registered installers for both cavity and external insulation at the below links:

Cavity Wall Insulation >>>>

External Wall Insulation >>>>

You can find a list of NSAI Agrement Certificates at the below link:


There is much more useful information to assist you make good choices for your project on the NSAI website at the below link:


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