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Insulmax® Your

The quintessential Kiwi cladding

Weatherboard homes are classically kiwi - charming, understated and full of character. However, most weatherboard homes built before 1978 are missing something integral to their construction - wall insulation.

While some homeowners undertake the daunting task of removing wall linings to add segment insulation, this is an expensive, inconvenient and obtrusive option and often strips villas of their charming character.

Insulmax® retrofit wall insulation is the perfect way to finish the insulation of your weatherboard home and bring it closer home standards.

Why insulate the walls of your weatherboard home ?

Insulation reduces heat loss from your home allowing it to retain more heat making it warmer and easier to heat.  Heating bills can be reduced and your home will feel drier, quieter and generally a more confortable and healthy place to live.  When you’re in a newer home, you’ll notice how easy it is to maintain a comfortable, dry and healthy indoor environment. Insulmax® can make this a reality in your older home as we increase your home's insulation towards modern standards.

How we insulate your weatherboard walls


Comprehensive pre-assessment report of your home to ensure you and your family get the full benefit of Insulmax®.


A trained and licensed Insulmax® building assessor completes an assessment of your home to ensure the most efficient install process. This assessment may also identify small areas of maintenance e.g. damaged weatherboards. The thirty two point property assessment is free of charge and can be carried out without accepting a quotation. 

During the assessment a quotation can be prepared and options for your install discussed. Because Insulmax® is certified to be installed via all common external claddings or internal linings the choice is largely down to customer preference.

Upon acceptance of your quotation, your Insulmax® representative will prepare and lodge (on your behalf), an application with your local council*  for a Building Consent or Sch1 Sec2 Exemption.  We strongly advise that you keep a copy of the council approved application or council letter advising widespread exemption for your records. This is particularly valuable when the time comes to sell your property.

*Since 2010 all forms of external wall insulation have required an application to your local council for either Building Consent or Exemption, although some councils offer a more widespread exemption. Your local Insulmax® representative can advise you of your councils requirements.


Wall cavities are accessed and filled with Insulmax® mineral fibre insulation, generally within a day. Leave a cold home in the morning and get back to an insulated one after work !


The installation of Insulmax® is carried out by trained, licensed and audited Insulmax® installers to the standards of Insulmax® NZ Ltd. We absolutely pride ourselves on the professional knowledge of our staff and the quality of our installs.

The process involves :

  1. All wall cavities are located by various techniques including the use of high resolution thermal imaging equipment.
  2. A 16mm (smaller than a 10 cent coin) hole is used to access each cavity via the weatherboard cladding. 
  3. Install machinery is proprietry to Insulmax® and is calibrated on each install to achieve the optimum density. A sample box is filled and weighed to ensure complete cavity fill and correct density. At installed density Insulmax® will not settle or slump.
  4. All wall cavities are filled with Insulmax® mineral fibre insulation. Insulmax® is installed dry with no binders, glues, formaldehyde or volatile compounds so it's safe to stay home during the install.
  5. High resolution thermal imaging equipment is used during the install to ensure that all wall cavities have been filled with Insulmax® insulation

Finishing your Install

Thermal imaging equipment is used to ensure all areas are insulated before install holes are filled and finished. Your install is covered by a written 50 year Insulmax® guarantee* to accompany the approved council application.

Finishing your Install

Our aim is to leave your home with negligible sign that it's been insulated and we pride ourselves in finishing your home as if it were ours!

The process involves :

  1. Each install hole is filled with a two part filler.  The small 16mm installation hole makes filling straightforward and the finished hole difficult to spot. 
  2. Filler is sanded flush. 
  3. Smooth filler is painted with a primer and top coat** paint system to provide a weathertight and durable finish.
  4. Seven to fourteen days after completion you will receive a written "Insulmax® Certificate of Completion" guaranteeing your install for 50 years which we recommend you keep with your council consent paperwork.

Insulmax® insulation contributes an R value of 2.8 to the walls of a typical weatherboard home - you’ll want to adjust your heating settings accordingly!

* Each install is accompanied by a 50 year gaurantee except external paint systems which are guaranteed for 7 years

** Top coat can be provided by the customer or by your installers, by prior agreement with your Insulmax® representative

What other weatherboard home owners have to say about Insulmax®

Why Choose

Install assured

Insulmax® installers are independently trained, licensed and audited to assure that Insulmax® standards are maintained. High resolution thermal imaging cameras are used during and after every install to locate cavities and to assure that your walls have been completely insulated.

National support with local service

Insulmax® is the largest and most specialised retrofit wall insulation group in New Zealand. Our owner operated branches throughout the country offer local service, backed by national support and experience. Thousands of NZ home owners are already enjoying the benefits of Insulmax® retrofit wall insulation.

Ultimate install flexibility

Insulmax® is certified to be installed through ALL common exterior claddings and internal linings with or without building paper giving you the choice of how we install your home, whatever its age or cladding. We are certified to install the exterior walls of ALL types of older homes, with or without building paper.

Smallest installation hole

Insulmax® are the "keyhole surgeons of the insulation world", using an installation hole smaller than a 10 cent coin (16mm). The smallest hole size minimises the impact on your home and leaves finished installation points difficult to spot with lasting durability.

Guaranteed and certified

The Insulmax® Retrofit Wall Insulation Method was the first NZ retrofit wall insulation system to achieve CodeMark certification which demonstrates compliance with the New Zealand Building Code and is approved by every Council in N.Z. Each wall insulation install is accompanied by a 50 year written guarantee.

Environmentally conscious

Insulmax® saves tons of building materials from ending up in landfills by eliminating the need to remove wall linings. Insulmax® is made from inert minerals and is composed of 84% post-consumer waste. It is CFC and HCFC free and is classified as having zero Ozone Depletion potential and zero Global Warming potential.

Trusted in Europe and UK

Manufactured in Europe to ISO9001 standards and trusted for over 20 years in the walls of over 1 million UK homes.