How much Insulation do you need?

It all depends on how cold it gets where you live. Here are the recommended minimum insulation levels (R-values) for existing homes:

MINIMUM RECOMMENDED R-VALUES FOR EXISTING HOMES

North Island
(excluding Central Plateau)
South Island and Central Plateau
Ceilings with 0-75mm of existing insulation R2.8 blanket or R3.4 segment insulation R3.2 blanket or R4.0 segment insulation
Ceilings with 75-120mm of existing insulation R1.8 blanket insulation R2.4 blanket or R2.6 segment insulation
Underfloor R1.4 bulk insulation R1.4 bulk insulation
Walls Check the thickness of your wall cavity and find the highest R-value product at that thickness

How important are climate zones?

New Zealand is divided into three climate zones, ranging from relatively warm to cool and frosty during winter.

CLIMATE ZONE 1

All areas north of, and including, Franklin District. Thames-Coromandel is also part of Climate Zone 1.

CLIMATE ZONE 2

All North Island areas not covered by Climate Zones 1 and 3.

CLIMATE ZONE 3

All of South Island and North Island Central Plateau (Taupo and Ruapehu Districts, and north of Rangitikei District).