Retrofit Insulation

Retrofit Insulation and Rental Homes

Retrofitting insulation into existing homes and rental properties.

A well-insulated home is warmer in winter, cooler in summer, and helps keep your energy costs down. But many older New Zealand houses have little or no adequate insulation, making them hard to heat, uncomfortable to live in, and potentially unhealthy.

Retrofitting insulation is an important consideration for all older houses, not just your family home. All rental properties will need to have ceiling and underfloor insulation installed (where practicable to do so) by 1 July 2024. 

Learn more about insulation and rental properties in New Zealand here.

Naturally, the best time to add insulation to a building is when it is being built, but there are many cost-effective ways to retrofit insulation to an existing home or rental property.

Underfloor and ceiling insulation are usually the easiest ways to add insulation to an existing property, but not all ceilings and floors provide adequate access. 

Southtile will work with you to assess your property’s insulation needs, help you select the right solution for your home, and install it to a high standard.


Choose the best type of insulation for your situation: underfloor, ground moisture barrier, and ceiling insulation.

Southtile uses high-quality insulation products from reputable suppliers to solve your retrofitting insulation problems.

We work with the following brands to make your home or rental property warm, dry, and compliant with the relevant legislation:

  • Autex: GreenStuf is proudly made for Kiwis by Kiwis, manufactured right here in New Zealand. Backed by a 50 Year Durability Warranty. 
  • Brownie: Brownie is the formaldehyde-free range of glass mineral wool insulation manufactured by PGF Insulation. It uses a formaldehyde-free binder that is free of formaldehyde, phenol or any other artificial chemicals. It is naturally brown and helps you improve indoor air quality and achieve a healthier and safer home by reducing your overall formaldehyde exposure.
  • Earthwool: Earthwool glasswool is made using up to 80% recycled glass and sand, has no added formaldehyde, is non-combustible, and is naturally sound-absorbant. It comes with a full 50-year warranty. 
  • Expol: Expol polystyrene underfloor insulation is the easy insulation choice for timber floors. Expol premium underfloor insulation meets and exceeds the new residential tenancies act requirements. 
  • Mammoth Insulation: Mammoth™ insulation is made in NZ from 100% polyester and designed to create warmer healthier environments. Mammoth™ includes fibres from recycled plastic bottles, are Red List Free and is 100% recyclable.
  • Pink Batts: Pink Batts are made with over 80% recycled glass, has Environmental Choice New Zealand accreditation, and GREENGUARD Certification, and have a range of products for different situations. 
  • Premier Insulation: Premier Insulation is made from the world’s most popular insulation material, glass wool, which is non-combustible and sustainable. Premier manufactures its products in New Zealand using fibres from recycled plastic bottles, is fully recyclable, and uses near-zero waste production practices.


Southtile are specialists in all forms of insulation.

Southtile supply and install retrofit insulation at competitive rates. 

Call Southtile Christchurch today to discuss your ceiling insulation, underfloor insulation, and ground vapour barrier needs.