# Minimum Ceiling Heights (NCC 2025)

The NCC's minimum ceiling heights room by room — 2.4 m for living, 2.1 m for wet and utility rooms — plus the two-thirds rule for raked ceilings and attics.

- Canonical HTML: https://www.chippy.tools/building-codes/au/rooms/minimum-ceiling-heights/
- Publisher: Chippy Tools
- Updated: 2026-09-06
- Market: au
- Code edition / reference: NCC 2025
- References: HP 10.3


## The requirement

A habitable room needs at least **2.4 m (2400 mm)**, floor to ceiling. That covers bedrooms, living rooms and dining rooms. Wet and utility rooms like the kitchen, bathroom, laundry and toilet only need **2.1 m (2100 mm)**. Over a stair you need **2.0 m (2000 mm)** of clear headroom (NCC 2025, Housing Provisions clause 10.3).

Here’s the quick version:

| Where                                                                  | Minimum ceiling height (NCC 2025) |
|------------------------------------------------------------------------|-----------------------------------|
| **Habitable rooms** — bedroom, living, dining                          | **2.4 m (2400 mm)**               |
| Kitchen, bathroom, laundry, toilet, pantry, storeroom, hallway, garage | **2.1 m (2100 mm)**               |
| Over a stairway or ramp                                                | **2.0 m (2000 mm)**               |

A habitable room is one people live in. Think bedrooms, living rooms, dining rooms and the like. A kitchen is a habitable room under the NCC definition, but it has its own 2.1 m height rule. Do not apply that exception to other living spaces.

You measure the height from the finished floor straight up to the ceiling. Over a stair you measure the clear headroom up from the nosing line, not off each tread. The nosing line is the straight line that touches the front edge of every step.

**Diagram labels:** 2.1 m; 2.0 m; 2.4 m

NCC 2025 Housing Provisions 10.3

## Sloping and raked ceilings

Not every ceiling is flat. Raked ceilings and attic rooms drop away at the edges. You can’t hold the full height across the whole room. The rule book allows for that.

You only have to keep the required height over two-thirds of the floor area:

- Habitable room: **2.4 m** over two-thirds.
- Habitable attic room: **2.2 m** over two-thirds.
- Non-habitable room: **2.1 m** over two-thirds.

There’s one more part to it. When you work out that two-thirds, leave out any part of the room where the ceiling is under **1.5 m** high. That low strip near the wall doesn’t count as floor area for the test.

## Work it out by hand

You’ve got a raked bedroom, so it’s a habitable room. The ceiling slopes from a low wall up to a ridge. Does it pass?

1. **Drop the low bit.** Measure in from the low wall to where the ceiling reaches **1.5 m**. Everything below 1.5 m is left out. Say the room is 4.0 m × 3.0 m, and the strip under 1.5 m eats up 0.5 m along the 3.0 m wall. That’s 0.5 × 3.0 = 1.5 m² gone. Floor area for the test is now 12.0 − 1.5 = **10.5 m²**.
2. **Find two-thirds.** Two-thirds of 10.5 m² is **7.0 m²**.
3. **Check the height.** Walk the tape across the room and mark where the ceiling drops below **2.4 m**. As long as at least 7.0 m² of that floor sits under a ceiling of 2.4 m or higher, the room passes.

The 10.5, 7.0 and 1.5 m² figures above are just an example to show the steps. Your room will give you different numbers. The heights (2.4 m, 1.5 m) are the code minimums.

## Related

- Part of the [NCC rules for Australian chippies](https://www.chippy.tools/building-codes/au/ncc-for-chippies/) — the plain-language pillar, with the state-by-state adoption tracker.
- Building the stairs those 2.0 m headroom limits sit over? See [NCC stair requirements: riser, going & the 2R+G rule](https://www.chippy.tools/building-codes/au/stairs/ncc-stair-requirements/).
- Fitting out a raised floor or landing? Check [balustrade height requirements](https://www.chippy.tools/building-codes/au/stairs/balustrade-height-requirements/).

## Sources

- **NCC 2025, ABCB Housing Provisions Standard, Part 10.3 “Room heights” (clause 10.3.1)** — the minimum floor-to-ceiling heights for habitable and non-habitable rooms, the 2.0 m over stairs and ramps, and the two-thirds rule for sloping ceilings (including the under-1.5 m exclusion). Confirm the figures at [NCC room heights, clause 10.3.1](https://ncc.abcb.gov.au/editions/ncc-2025/adopted/housing-provisions/10-health-and-amenity/part-103-room-heights). *(Confirmed against the NCC 2025 Housing Provisions Standard, verified 2026-07-28.)*


Content adapted from the National Construction Code 2022, provided by the Australian Building Codes Board under the CC BY 4.0 licence.

This page is general information for tradespeople and is not compliance, engineering or legal advice. Requirements are subject to state and territory variations and adoption timing. Always confirm requirements with your building certifier and relevant state authority.


## Frequently asked questions

### What is the minimum ceiling height in a house in Australia?

It depends on the room. A habitable room — a bedroom, living room, dining room — needs at least 2.4 m (2400 mm), floor to ceiling. Wet rooms and utility rooms like the kitchen, bathroom, laundry, toilet, pantry and hallway only need 2.1 m (2100 mm). Over a stair, the clear height drops to 2.0 m (2000 mm).

### Does a kitchen need a 2.4 m ceiling?

A kitchen is a habitable room, but clause 10.3.1 gives it a separate 2.1 m (2100 mm) minimum. The same 2.1 m applies to bathrooms, laundries, toilets, pantries, storerooms, hallways and a garage.

### How much headroom do you need over a staircase?

At least 2.0 m (2000 mm) clear. You measure it straight up from the nosing line — the line that touches the front edge of every step — not off each tread.

### How do the rules work with a sloping or raked ceiling?

You only have to hold the required height over two-thirds of the floor area. That's 2.4 m for a habitable room, 2.2 m for a habitable attic room, and 2.1 m for a non-habitable room. When you work out the two-thirds, leave out any floor where the ceiling is under 1.5 m.

### What counts as a habitable room?

Bedrooms, living rooms, dining rooms, studies and kitchens are habitable rooms. Kitchens have a separate 2.1 m minimum. Bathrooms, laundries, toilets, hallways and storerooms are non-habitable rooms with a 2.1 m minimum.