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High Density (HD) High Performance Insulation

"the ultimate way to insulate homes"

HD insulation is a significant improvement in technology and thermal performance when compared to low density (common) insulation.

How IT Works

The two parameters that make HD insulation superior is reduced air flow and thermal storage. 

Air Flow: Traditional low density insulation materials suffer from air movement through the insulation. Although designed to have air pockets that trap and slow down air movement and forms part of the insulations performance, enough air still moves through which causes additional heat loss. Low density fibres are also difficult to achieve a 100% fill of a cavity while still maintaining a constant thickness. Because of this most installations are not optimized and fall short of the desired performance and building code criteria.

HD insulation however is designed and manufactured to a much higher level of density meaning the fibres are air layered and then compressed together to form a very tight and semi ridged material. This reduces air movement considerably, thereby reducing heat loss. Installation is much easier to achieve a 100% precise fit in the whole cavity while maintaining the constant desired thickness. 

Thermal MassThermal mass within the insulated portion of a house can serve to balance and smooth out internal temperatures, and particularly beneficial in New Zealand’s climate that can experience big temperature fluctuations within 24 hours. Basically thermal mass will absorb heat when air temperatures are higher than the mass, and then release thermal energy back when the surroundings are cooler. This is an added characteristic than the insulations thermal R-Value. With higher mass insulation more heat is stored for a time within the insulation giving it time to radiate back into your environment. Combined with internal jib lining further enhancing the mass affect, radiant type heating can be a beneficial heat source by directly heating the surfaces. The same applies on a sunny day, the radiant energy from the low winter sun angle shines inside warming up the surfaces. Our HD wall insulation at 90mm thick is 3.6 kilograms per sqm compared to our highest quality low density @ 90mm thick is 1.95 kilograms per sqm.


  • State of the art manufacturing plant using recycled plastic bottles - 100% recyclable.
  • Compression fitting - forms a perfect flat consistent surface.
  • No slumping, creasing, bulging or decay over time.
  • High Durability - performance will remain for the rest of the buildings life.
  • Easily accommodates wiring and plumbing.
  • Retains heat (light thermal mass).
  • Fit for Purpose - delivers its stated R- value to secure building code criteria.
  • Environmental Choice Certified.
  • Non irritant, odourless, and chemical free.
  • Noise Reduction Coefficient (NRC) of 1.05 @ 90mm thick. 


  1. Installs perfectly, a high quality installation will always ensure that insulation will perform at its stated R- value. Moreover, recent research shows that HD insulation often exceeds its designed performance in situ (r-value increases as outside temperatures drop).
  2. Cut slightly oversize for the gap between two building members such as studs and dwangs. - slightly oversized for the gap between building members such as studs and dwangs. This type of fitting guarantees a millimetre perfect installation and completely seals leaving no gap for air movement and heat loss.
  3. Pipes and wires are buried between two 45mm layers reducing convention air movement through wall cavities preventing unwanted air infiltration.
  4. HD insulation is the ultimate in durable - it will not slump in the walls over time and won’t open gaps for air to circulate through. Particularly important for wall and underfloor insulation that is subjected to gravity forces.
  5. HD insulation is hydrophobic (repels water) which means you can insulate before the framing is covered with a building wrap. Exterior corners and other areas around the building that are always left uninsulated because they cannot be done from the inside can be insulated before hand. These areas are responsible for very significant thermal losses through the building envelope. BRANZ research indicates that these exposed parts of the thermal envelope can significantly reduce the overall R - value of walls by 50% or more

    HD installation photos

    For more information about this exciting product please contact us or call


04 939 0313

Postal Address

PO Box 38-028
Wellington Mail Centre, NZ

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