Installing ceiling insulation

Use a trained professional to install or upgrade your insulation, as even small installation faults can affect its performance or create safety hazards.

Having a professional install insulation

We recommend using a trained professional installer who:

  • works to the New Zealand insulation installation Standard NZS 4246:2016.
  • has completed the insulation installer training of the Insulation Association of New Zealand (IAONZ).

Shop around to get more than one quote, so you can compare prices.

?New Zealand Standard for installing insulation

DIY checklist

Things to consider before you begin

  • New Zealand Standard NZS 4246:2016 contains everything you need to know about installing insulation. It's easy to follow and it's free to download (see link below). For rental homes, regulations require that insulation gets installed in accordance with this standard.
  • Safety - read and follow the Health and Safety advice in Appendix B of New Zealand Standard NZS 4246:2016. If you're not sure, get a professional to install the insulation for you.
  • Ceiling space - check if your house has a ceiling space. If not, it could be tricky to install, but it may still be possible to put insulation in your skillion roof or cathedral ceiling (see link below).
  • Existing insulation - a quick look in your roof space will tell you if you have any insulation already. If there is, you'll still want to check what state it's in (see link below).
  • Leaks and electrical issues - check your roof and any plumbing in the roof space for leaks. Check that your electrical wiring and installations are in safe condition. You should fix any issues before insulating.
  • Insulating around heat sources - having the right gaps between ceiling insulation and heat sources like recessed downlights, chimneys, flues or extractor fans is important for fire safety. Refer to New Zealand Standard NZS 4246:2016 for detailed requirements.
  • Multi-storey homes - only the upper ceiling between your home and the outside needs to be insulated. You don't need to insulate the ceiling between floors except above or below unheated rooms like laundries, workshops or garages.

?Checking existing ceiling insulation

?Insulating skillion or flat roofs

Insulation regulations for rental homes - Tenancy Services website