Isometric model of a Queensland house lot with an elevated weatherboard house and a separate granny flat, on a warm-to-cool gradient background.

The Queensland Housing Code explained: what changed on 1 September and when it applies to your job

In short

  • The Queensland Housing Code (QHC) was published on 3 August 2026 and commenced on 1 September 2026. It replaces QDC Parts 1.1 and 1.2 for detached houses, secondary dwellings and Class 10a buildings.
  • Commenced does not mean it applies everywhere. From 1 September 2026 to 1 September 2029, the QHC applies in a council area only once the planning scheme is amended to say how it applies.
  • Where a council has not adopted it, the previous QDC Parts 1.1 and 1.2, or the planning scheme’s own siting provisions, still apply. From 1 September 2029, the QHC applies anyway.
  • Chapter 1 covers lots under 450 m². Chapter 2 covers lots of 450 m² and over. Councils can vary many of the default numbers.
  • A granny flat (secondary dwelling) is capped at 50 m² internal floor area, or 60 m² on a Chapter 2 lot of 1,000 m² or more.

Correct as at September 2026.

If you design houses in Queensland, you have probably had the question already. “Does the new Housing Code apply to this job?” The answer is less obvious than the headlines suggest, and getting it wrong means drawing to the wrong setbacks.

Here is what actually changed on 1 September, and how to check which rules sit behind the site you are working on today.

What the Queensland Housing Code is

The QHC is the new design and siting code for detached housing in Queensland. It lives inside the Queensland Development Code (QDC): Chapter 1 is QDC Part 1.1 and Chapter 2 is QDC Part 1.2. It replaces the versions of those parts published on 11 March 2010.

It covers a single Class 1 building, a dwelling house with a secondary dwelling, and associated Class 10a buildings and structures, in any zone where a dwelling is a permitted use. It does not apply in priority development areas or tourist parks.

What changed on 1 September

The QHC commenced on 1 September 2026. That date started a three year transition, not an overnight switch. Business Queensland puts it plainly: during the transition, the QHC applies in a local government area only if the planning scheme is amended to specify how it applies.

So on any given job right now, one of three rule sets is in play:

  • The QHC, if the council has amended its planning scheme to adopt it.
  • The previous QDC Parts 1.1 and 1.2, if the council has not.
  • The planning scheme’s own alternative siting provisions, where the scheme has them.

If a council still has not adopted the QHC by 1 September 2029, it applies at the end of the transition regardless.

Practical step: before you set out a new house, check whether the council’s planning scheme has been amended to adopt the QHC. Put the answer, and the date you checked, on the file. If the certifier asks which rules you designed to, you will have the answer.

The key numbers, by chapter

These are the default acceptable solutions. Adopting councils can vary many of them under section 33 of the Building Act, so treat them as the starting point, not the final word.

StandardChapter 1 (lots under 450 m²)Chapter 2 (lots 450 m² and over)
Height, Class 1 and 28.5 m8.5 m
Height, Class 10a4.5 m4.5 m
Front setback, external walls3 m5 m
Side setback1 m1.5 m
Rear setback, ground storey3 m4 m
Rear setback, second storey2.5 m3 m
Site cover65% (lots 250 m² or less), 60% (over 250 m²)50%
Private open space15 m², 3 m minimum dimension20 m², 4 m minimum dimension
Parking2 spaces per dwelling, at least 1 in a garage or carport. A third space for a secondary dwelling, tandem allowed.

Height gets an extra 1.5 m where the slope of the site exceeds 15%. The side and rear figures above are for Class 1 and 2 buildings. Garage, carport and secondary frontage setbacks have their own rules, so check the code tables for those rather than assuming the wall setbacks carry across.

Granny flats under the QHC

This is where most of the enquiries are coming from. A secondary dwelling has a maximum internal floor area of:

  • 50 m² on a Chapter 1 lot
  • 50 m² on a Chapter 2 lot under 1,000 m²
  • 60 m² on a Chapter 2 lot of 1,000 m² or more

A detached single storey secondary dwelling can sit 1 m from the side and 1.5 m from the rear on a Chapter 1 lot, or 1.5 m and 2 m on a Chapter 2 lot.

If you are designing a small detached home in Queensland, the energy side changed too. QDC MP 4.1 version 1.16 commenced on 14 August 2026 and added new thermal performance pathways, including a 5-star option for small homes of 50 m² or less. That is a separate code from the QHC, with a separate start date, so keep them apart on your drawings and in your advice.

What to do on your next Queensland job

  1. Confirm the lot size, because that sets Chapter 1 or Chapter 2.
  2. Check whether the council has adopted the QHC in its planning scheme, and whether it has varied any defaults.
  3. If it has not adopted the QHC, design to QDC 1.1 or 1.2 or the scheme’s own provisions, and tell the client the rules may change before 1 September 2029.
  4. Keep the NCC edition in view. Queensland stays on NCC 2022 until 30 April 2027, and NCC 2025 applies from 1 May 2027. A house designed now may be approved under one and built well into the other’s life.

Want the whole thing on three pages? Our free Queensland Housing Code guide covers the transition flowchart, the Chapter 1 and 2 numbers, granny flats and the August energy pathways. Get the free Queensland guide.

CPD for Queensland designers

A dedicated Queensland Housing Code course is in development. In the meantime, these live courses cover the approvals and NCC transition questions that sit around it:

For what Queensland professionals need each year, see CPD in Queensland, the national CPD requirements guide and the CPD deadlines calendar.

Frequently asked questions

When did the Queensland Housing Code start?

The Queensland Housing Code was published on 3 August 2026 and commenced on 1 September 2026. It started a transition period that runs to 1 September 2029.

Does the Queensland Housing Code apply in my council area?

Only if your council has amended its planning scheme to specify how the Queensland Housing Code applies. Until then, the previous QDC Parts 1.1 and 1.2 or the scheme’s own siting provisions continue to apply. From 1 September 2029 the code applies in every council area.

Which chapter of the Queensland Housing Code applies to my lot?

Chapter 1 (QDC Part 1.1) applies to lots under 450 m². Chapter 2 (QDC Part 1.2) applies to lots of 450 m² and over.

How big can a granny flat be under the Queensland Housing Code?

A secondary dwelling can have a maximum internal floor area of 50 m² on a Chapter 1 lot or a Chapter 2 lot under 1,000 m². On a Chapter 2 lot of 1,000 m² or more, the limit is 60 m².

Can councils change the Queensland Housing Code numbers?

Yes. Adopting councils can vary many of the default acceptable solutions, including height, setbacks, site cover and parking. Always check the planning scheme for local variations before you set out a design.

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