Good quality windows and doors deserve a good quality window installation.
And that means they should be installed recessed into your wall; not hung out over the cladding as is so commonly done!
In other words, the warm barrier down the middle of the glass and down the middle of the frame needs to be CONNECTED to the warm barrier of insulation in your wall.
If your windows are not installed correctly, here are the downsides that you may experience:
- Heat loss through the edge of the window meaning higher heating bills
- Condensation forming on your window frames, even if they are thermally broken
- Potential mold growth in these areas where the condensation forms
- A cold, drafty feeling when you come close to the window
Ok sure, but surely everyone does this right?
Unfortunately, it’s unlikely. The fact is, nearly all thermally broken or higher performance windows in New Zealand are installed the wrong way, and it remains the default setting in the building code. This issue has arisen very uniquely in the New Zealand market, due to the way the building code works, the products which have been available, and the industry knowledge around thermal performance… and it’s time we all fixed it!
Fine, show me.
Needless to say, Stärke has a solution for recessing our high-performance windows, known as the AMBIANCE Inline Window system. Contact us today regarding your project – we’re keen to make a difference.
But what about the different costs?
Thankfully, there is almost no difference in material costs between installing your window right, and installing it wrong. Give us a call or email sales@starke.co.nz to price up your project!
Window installation psi-value and fRSI value Interactive Table
The below chart contains the Psi value and fRSI values of different installation methods. You can sort and filter to choose the best combination of frame and installation position for your project requirements. The data shown is taken directly from PHINZ High-Performance Construction Details Handbook.
| Detail Type | Psi – W/(mK) | fRSI | Rating |
|---|---|---|---|
| Solid Aluminium – Head | 0.135 | 0.118 | Poor |
| Solid Aluminium – Jamb | 0.14 | 0.12 | Poor |
| Solid Aluminium – Sill | 0.065 | 0.127 | Poor |
| Thermal Aluminium – E2/AS1 Head | 0.208 | 0.302 | Poor |
| Thermal Aluminium – E2/AS1 Jamb | 0.172 | 0.307 | Poor |
| Thermal Aluminium – E2/AS1 Sill | 0.106 | 0.329 | Poor |
| Thermal Aluminium – Recessed to flush with BL – Head | 0.088 | 0.422 | Excellent |
| Thermal Aluminium – Recessed to flush with BL – Jamb | 0.084 | 0.42 | Excellent |
| Thermal Aluminium – Recessed to flush with BL – Sill | 0.059 | 0.421 | Excellent |
| Thermal Aluminium – Recessed to centre of wall – Head | 0.074 | 0.421 | World-Class |
| Thermal Aluminium – Recessed to centre of wall – Jamb | 0.081 | 0.419 | World-Class |
| Thermal Aluminium – Recessed to centre of wall – Sill | 0.069 | 0.419 | World-Class |
| uPVC – E2/AS1 Jamb | 0.088 | 0.607 | Poor |
| uPVC – Recessed to flush with BL – Head | 0.079 | 0.648 | Excellent |
| uPVC – Recessed to flush with BL – Jamb | 0.054 | 0.649 | Excellent |
| uPVC – Recessed to flush with BL – Sill | 0.04 | 0.624 | Excellent |
| uPVC – Recessed to centre of wall – Head | 0.041 | 0.639 | World-Class |
| uPVC – Recessed to centre of wall – Jamb | 0.04 | 0.64 | World-Class |
| uPVC – Recessed to centre of wall – Sill | 0.04 | 0.631 | World-Class |
| Timber – Recessed to flush with BL – Head | 0.062 | 0.687 | World-Class |
| Timber – Recessed to flush with BL – Jamb | 0.045 | 0.692 | World-Class |
| Timber – Recessed to flush with BL – Sill | 0.047 | 0.692 | World-Class |
