This is a game changer in thermal performance

The Centrafix™ installation method is an alternative solution to the New Zealand Building Code standard installation method.

This new BRANZ Appraised and Codemark Certified installation method recesses the window or door back inside the building wall, minimising thermal losses which occur in a typical installation. This aligns all insulation elements – wall, window frame, glazing – and prevents cold air from circulating around the window and door frames. 

BRANZ appraised. Appraisal No. 1188 (2023)

New Zealand Des. Reg. No. 429382

Video is indicative of the installation method. Refer to our technical resources for full installation details.

What does Centrafix™ do?

Centrafix™ is a unique, New Zealand designed installation method that is exclusively available in Metro Series ThermalHEART® windows and doors.

Increases the thermal performance in your home by over 20%

This innovative installation method aligns all insulation elements – wall, window frame, glazing – which prevents cold air from circulating around the window and door frames, improving the whole window system’s thermal performance.

Recesses into the building wall

Centrafix™ is designed to safely and efficiently recess a window or door unit from the front face of the cladding back into the building wall, minimising the thermal losses that occur in current installation methods.

Aligns all insulation elements

Recessing the window and door units realigns the insulating elements of the window frame and glazing with the insulation elements of the wall, improving thermal efficiency.

Offers clean, contemporary lines

The joinery perimeter sits flush against the exterior, while the body of the window is recessed, enhancing the contemporary aesthetic of your project.

Complies with the New Zealand building code

Centrafix™ is a BRANZ Appraised and Codemark Certified alternative solution to NZBC E2/AS1.

Offers a Passive House variant

The Centrafix™ window installation system, can be specified with higher performance glazing, frames and special insulating elements around and within the window frame to achieve passive house levels of thermal performance.

Completes your thermal window system

Your windows and doors are a complete system with each component (the frames, the Insulated Glazing Unit, the installation) contributing to the overall performance and comfort of your home. For the ultimate in thermal performance, the whole window system needs to work together to complete your thermal window system.

Centrafix™ installation vs E2/AS1 installation

When viewing the installation methods side-by-side, you’ll notice that the full face of the E2/AS1 frame and glazing panels sit outside the wall, in line with the cladding meaning it’s fully exposed to the colder external temperatures. E2/AS1 cavity construction installation is the standard installation method as stipulated in the New Zealand Building Code.

The Centrafix™ installation has the core of the frame and the glazing panels in line with the wall structure and insulation elements, helping to protect it from the external temperatures and preventing the loss of heat through the frame.


Which ranges can be installed using Centrafix™ technology?
Centrafix™ is exclusively available in Metro Series ThermalHEART® windows and doors. Full details of Metro Series ThermalHEART® with Centrafix™ can be found on EBOSS or in our Specifier Guide.
What is the compliance path for Centrafix™?
Centrafix™ has been independently assessed by BRANZ to ensure the product meets all relevant Building Code performance requirements.

BRANZ appraisal Number: 1188 [2023]
Codemark Certificate CMNZ10033
Where can I find installation information?
You can find detailed installation information in the Centrafix™ System Guide here. This guide is updated as required to ensure it contains the latest installation information.

We have interactive animated 3D assembly models available for several key Metro Series ThermalHEART with Centrafix™ products which allow you to quickly and easily understand how the components fit together. View the  Centrafix™ resources here.
Why is the WEERS modelled thermal performance lower than the advertised performance?
WEERS combines the thermal performance of the frame and glazing, together with the size of the window to calculate a rating. The frames are modelled in isolation which doesn’t consider the effects of the building construction or the unique installation advantages of the Centrafix™ window system. Our figures are generated using Flixo modelling software and represent the performance of an installed unit.
*Centrafix™ comparison figures are based on complete thermal modelling of an average house lot of products installed in 90mm timber framing. The standard installation benchmark was calculated by modelling the same house lot of comparable products using a typical E2/AS1 cavity construction installation on 90mm timber framing.

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