PM23 H1 Guide TUMU 210x287mm 4.0 LR - Flipbook - Page 6
BUILDING
ELEMENTS
NEW CONSTRUCTION R-VALUES
FOR WINDOWS & DOORS
The first phase of implementation – from
3 November 2022 – will see windows and doors in
houses in all areas of the country require a rating of
R0.37.
This means minimum compliance can be achieved
through a change in glazing, and specifically
through the use of high-performance, double glazed
Low E Insulated Glass Units (IGUs) in aluminium
frames.
NEW CONSTRUCTION R-VALUES
FOR WALLS
NEW CONSTRUCTION R-VALUES
FOR CEILINGS
From 1 May 2023, walls in housing across
New Zealand will have to meet a minimum
construction R-value of R2.0. This is the same
as applied to the previous Zone 3 in the South
Island. To achieve this, walls will require an
insulation material with an R-value of R2.4 or higher.
The new construction R-value for ceilings for all
New Zealand housing is R6.6, which is a significant
increase from the previous requirements – R2.9 and
R3.3 depending on the previous zoning.
The current wall construction will not have to change
to accommodate the increases. The new R-value
of R2.0 is achievable using standard 90mm
wall framing.
The insulation product R-values required will vary
depending on the construction materials used in
the project and the roof and ceiling designs. We will
see a larger variety of products considered due to
the type of roof and ceiling designs and the costs
involved with various methods of installation.
Due to the large increase in the construction R-value
required, we will see the introduction of some
new products to the residential new-build market.
Fibreglass and polyester insulation will remain the
most common products, but these will be installed
in different ways.
CEILING INSULATION
10%
TO
15%
Low E glazing achieves a lower rate of heat loss
due to thin layers of silver or other low emissivity
material on one side of the glass, which is enclosed
in double or triple glazing to protect the coating.
To achieve further insulation, an inert gas such as
argon is used between layers of glazing.
5%
TO
10%
IT’S IMPORTANT TO NOTE THAT MEETING
THESE R-VALUES IS BASED ON USING THE
SCHEDULE METHOD FOR COMPLIANCE.
WHEN USING THE CALCULATION OR
MODELLING METHODS, INDIVIDUAL
CONSTRUCTION ELEMENT R-VALUES MAY
BE HIGHER OR LOWER, DEPENDING ON
SEVERAL VARIABLES.
SEE PAGES 6-7 FOR MORE DETAIL.
35%
TO
However, once requirements are lifted to R0.46 or
R0.50, aluminium framing will not suffice. Thermally
broken aluminium, uPVC or timber framing with
double-glazed Low E IGUs will be required to meet
or exceed the standard.
50%
For Zones 3, 4, 5 and 6, those higher R-values
need to be met starting 1 May 2023. For
Zones 1 and 2, requirements will be lifted
to R0.46 on 2 November 2023.
10%
TO
NEW CONSTRUCTION R-VALUES
FOR FLOORS
From 1 May 2023, the minimum R-values for floors
will increase in all climate zones. The table above
shows the construction R-value required. The
previous R-value for the entire country was R1.3.
Increases to floor insulation are two-fold,
differing over climate zone – as with all building
elements – but also depending on whether you
have a concrete slab-on-ground floor or another
type (most commonly suspended floors).
10
20%
four climate zones – a move from R1.3 to R1.5 – is
greater than it appears.
slab-on-ground floors will need to achieve even
higher levels of insulation.
The new minimum construction R-values are lower –
R1.5 to R1.7 – for concrete slab-on-ground floors
than for other floor types – R2.5 to R3.0. According
to MBIE, this is because it’s much more challenging
for slab-on-ground floors to achieve significantly
higher R-values than with other types, such as
suspended timber floors.
That’s because the background calculation method
used for the 5th edition has changed. According to
BRANZ, the increase is the equivalent of going to
R2.0 under the previous approach. R1.5 means most
slabs in buildings under 300m² will be specified
with some combination of perimeter and under-slab
insulation.
It’s unlikely that there will be a big shift in the types
of products that can be used, but a change in the
installation methods will be needed. For example,
insulation added to non-slab-on-ground floors will
no longer be able to be held in place with staples
due to its increased thickness.
However, even the small increase required for
unheated slab-on-ground floors in the warmest
In the future, MBIE expects that this differentiation
between the floor types to be removed and
TUMU H1 GUIDE
The new R-value requirements are also different for
heated slab-on-ground floors. See table above.
11