NZ Ceiling Heights: Building Code and Housing Rules

Check both sets of rules

Do not choose a ceiling height from one headline. Check the code, your plans and the housing rules. Ask the council if you are unsure. Do this before you set the height of the frame.

G5 Interior Environment has no general house ceiling-height table. Its Acceptable Solution covers matters such as heating and space in certain buildings. That does not remove other rules for the room or access route.

What the housing regulations say

Housing Improvement Regulations 1947, regulations 2 and 10 give house age a set meaning. An existing house was built before those rules became law. A new house was built after that. A house built decades ago can therefore be a new house for these rules.

Regulation 10 sets these habitable-room heights:

For a sloping ceiling, the height applies over at least half the floor area. Leave out areas below 1.5 m when doing that test. Regulation 2 also includes a kitchen of at least 80 square feet in its habitable-room meaning.

Do not assume an owner-occupied house is exempt. Confirm how the regulations apply to the property and work. Check both the building consent and the housing rules.

Keep a clear site record

Before you mark the ceiling, note the room use and the height on the plans. Check finished floor layers too. They reduce the space beneath the ceiling. For a sloping ceiling, mark the height zones on a measured plan. Do not use a general room-height example to check stair headroom.

Sources

• MBIE G5 current Acceptable Solution.
• Housing Improvement Regulations 1947, regulations 2, 3 and 10.

Related

• New Zealand building-code hub.
• NZ stair and barrier rules.