Climate Zones
Changes to the Building Code mean that new houses will typically need to achieve higher R-values for the walls, windows and roofs. Most new houses are currently built to a standard set of R-values, shown in Table 1. These R-values will change as the new insulation requirements take effect.
The new R-values are listed in Table 2. These show the overall R-values for each part of the building, and are different to the R-value of the insulation that is actually installed. For example, a timber-framed wall will need insulation with an R-value of between 2.2 and 2.8 to achieve an overall R-value of 2.0 (the higher insulation R-value offsets the lower R-value of the timber framing).
Insulation values can be found in the BRANZ House Insulation Guide 2007.
| Zone 1 before 30/09/08 | Zone 2 before 30/06/08 | Zone 3 before 31/10/07 | |
|---|---|---|---|
| Roof | R 1.9 | R 1.9 | R 2.5 |
| Wall | R 1.5 | R 1.5 | R 1.9 |
| Floor | R 1.3 | R 1.3 | R 1.3 |
| Vertical glazing | - | - | - |
| Skylights | - | - | - |
| Zone 1 after 30/09/08 | Zone 2 after 30/06/08 | Zone 3 after 31/10/07 | |
|---|---|---|---|
| Roof | R 2.9 | R 2.9 | R 3.3 |
| Wall | R 1.9 | R 1.9 | R 2.0 |
| Floor | R 1.3 | R 1.3 | R1.3 |
| Vertical glazing | R 0.26 | R 0.26 | R 0.26 |
| Skylights | R 0.26 | R 0.26 | R 0.31 |