- ACTClass 2-9NCC 2022 (either-edition window to 2027)19 Aug 2026
Our Canberra project's DA was lodged in October 2026 but the building approval won't land until mid-2027. The certifier says we can still choose NCC 2022. Is that right?
Yes: a DA lodged before 1 November 2026 keeps the ACT either-edition election, so NCC 2022 can still be nominated even where the building approval issues after the 1 May 2027 mandatory-NCC-2025 date, until the DA expires.
Read the answer - SAClass 1aNCC 2022 + 2025 (split)28 July 2026
We're renovating a bathroom in Adelaide. The builder is working to NCC 2022 but the plumber says his work falls under NCC 2025. Can both be right on the same job?
South Australia is in a split adoption: building work follows NCC 2022 while plumbing and drainage follow NCC 2025, so a builder and a plumber can each be on a different edition of the same renovation.
Read the answer - TASClass 1aNCC 202228 July 2026
Our Hobart project got its building approval on 20 May 2026, while NCC 2025 was briefly in force in Tasmania. Which edition applies to our project now?
Approvals granted in Tasmania between 1 May and 4 June 2026 sit in a genuine gap: the reinstating Act has no savings clause, so neither edition can be assumed and written CBOS confirmation is the only safe course.
Read the answer - QLDClass 1aNCC 202223 July 2026
Our certifier says the study doesn't qualify as a habitable room because the window is only 9% of the floor area. How is natural light measured, and can we borrow light from the living room next door?
The 10% natural light rule is measured on light-transmitting area, net of framing, and a shortfall can be fixed three ways: a bigger window, a roof light at 3%, or borrowed light from an adjoining room that is glazed for both rooms combined.
Read the answer - TASClass 1aNCC 202223 July 2026
Our energy assessor specified R5.0 ceiling insulation for a climate zone 7 build, but the builder insists R4.0 is enough because the roof has sarking. Who is right?
Neither is automatically right: the zone 7 ceiling table turns on roof ventilation, reflective insulation and solar absorptance, not sarking, and R5.0 is only mandatory in one corner of the matrix.
Read the answer - WAClass 1aNCC 202523 July 2026
Our split-level has a short flight of five steps (about 850 mm total rise). The certifier wants a handrail on the main stairs but not there. Is that right?
Yes: a flight with a change in elevation under 1 m is exempt from the handrail requirement, while the main stairs need one on at least one side, continuous, at 865 mm or more above the nosings.
Read the answer - VICClass 1aNCC 202515 July 2026
I'm building brick veneer in Melbourne and my energy assessor says the walls need a drained and ventilated cavity. Is that right, and what exactly does it involve?
The assessor is right: in climate zone 6 a masonry veneer wall must have a drained and ventilated cavity at least 12 mm deep with 1,000 mm2 per metre of openings, and the requirement comes from condensation management, not the energy provisions.
Read the answer - NSWClass 1aNCC 202214 July 2026
How high does waterproofing need to extend on shower walls, and does the whole bathroom floor need to be waterproofed?
Shower walls must be waterproof to at least 1800 mm above the floor substrate. The rest of the bathroom floor usually only needs to be water resistant, with one waterstop-related exception worth knowing.
Read the answer - SAAll classesNCC 20259 July 2026
What is the maximum hot water delivery temperature at a bathroom basin or shower?
Heated water must be delivered at no more than 50 °C at a standard bathroom fixture, dropping to 45 °C in aged care, health care, schools and other high scald-risk settings. In SA this is already an NCC 2025 question.
Read the answer - WAClass 1aNCC 20259 July 2026
How high does a balustrade need to be on a deck or balcony, and when is one required at all?
A barrier is required wherever a fall of 1 m or more is possible, built to at least 1 m high on a deck or landing and 865 mm above stair nosings, with a 125 mm sphere rule for openings.
Read the answer - TASClass 1aNCC 20229 July 2026
What are the maximum riser and minimum going dimensions for stairs in a new house?
For a standard stairway in a Class 1a home the riser can be at most 190 mm and the going at least 240 mm, with the 2R+G slope relationship kept between 550 and 700 mm.
Read the answer - NSWClass 1aNCC 202230 June 2026
What are the minimum ceiling heights for a Class 1a dwelling?
The NCC requires 2.4 m in habitable rooms and 2.1 m in non-habitable rooms, hallways, stairways and ramps for a Class 1a dwelling.
Read the answer - VICClass 1aNCC 202527 June 2026
Where do smoke alarms need to go in a new Class 1a house, and must they be interconnected?
A new Class 1a dwelling needs AS 3786 smoke alarms on every storey and near bedrooms, mains-powered and interconnected so they all sound together.
Read the answer - QLDClass 1aNCC 202226 June 2026
What thermal performance rating does a new home need to meet under NCC 2022?
NCC 2022 raises new Class 1 homes to a 7-star NatHERS envelope rating plus a separate whole-of-home energy budget, with adoption dates varying by state.
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