The ban on Foil Insulation and what it may mean for you

At NZ house Surveys our inspectors frequently find Foil insulation installed in the subfloor of many New Zealand Homes. The product poses a serious safety hazard and owners and purchases are often unaware of the risk.

foil insulation installed underfloor

When was foil insulation banned?

In 2016 the Chief Executive of the Ministry of Business, Innovation and Employment declared a ban on the installation and repair of foil insulation in residential buildings with an existing electrical installation (e.g retrofitting foil insulation) under section 26 of the Building Act 2004. The ban came into force on the 1st July 2016, although it did not apply to any building work for which a building consent was issued to prior to this date. It will remain in force until it is amended or revoked by MBIE.

Any person who breaches the ban is liable for a fine up to $200,000 on conviction.

Foil insulation

What is foil insulation?

Foil insulation consists of a thin layer of heat-reflecting metallic foil, usually aluminium. It is most commonly found in flexible sheet or blanket form and may be attached to other flexible insulating materials such as wool or fibreglass.

Why has foil insulation been banned in New Zealand?

Foil insulation has been banned over safety concerns associated with the method of attaching the foil to the building and the compliance of this building method with the building code. The risk with installing and repairing foil insulation in a building with an existing electrical installation is that the person carrying out this work could accidently pierce a live electrical wire with the staples or nails that they are using to attached the foil to the building. The foil, being metallic, conducts electricity and can become live if it comes into contact with live electrical wiring – potentially enlivening the entire underfloor area or ceiling space of a building. Nylon fasteners also have some risk as they can split the insulation of the electrical cables and cause the wiring to come in direct contact with the foil insulation.

In retrofit situations insulation is often installed in dark and cramped conditions making it hard to see exactly where cables are located. Even if the retrofit has been completed without incident the foil can still be left electrically live, presenting a future electrocution risk.

Foil insulation is occasionally used for other purposes such as a moisture barrier. The ban still applies to the use of it for other purposes and the installation of it usually remains the same.

Foil insulation in panel form

Foil insulation has occasionally be supplied in panel form where the panels are bonded to rigid building materials. The ban excludes the installation and repair of foil that is supplied pre-fixed to rigid building materials as the installation method decreases the risk that a live electrical cable wild be accidently pierced.

My house has foil insulation – what does this mean for me?

If you have foil insulation installed in your home care needs to be taken when undertaking any work in the space where it is fitted. You need to ensure the power is switched off at the mains and take good battery lighting into the space with you. Always be cautious when working in any confined space close to electrical wiring.

In good condition the foil insulation can be left as is. However if the foil is in poor condition it will need to be removed and replaced. In rental properties where existing foil insulation is damaged, degraded, missing or incomplete, new non-electrically conductive underfloor insulation must be installed with an R-value of at least R 1.3. All insulation retrofitted for compliance with the RTA from 1 July 2016 must also comply with NZS 4246:2006.

Insulation replacement

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