Asset protection zones for subdivisions in NSW

An asset protection zone (APZ) is a strip of land kept low in fuel between houses and bushland, so a bushfire can't reach the houses with flames or deadly heat. For a new residential subdivision in NSW, the width comes from tables in Planning for Bush Fire Protection 2019. It depends on the type of vegetation, the slope of the land under it and the fire weather in your council area. Widths in the subdivision tables run from 5 metres to 56 metres.

On a rural fringe site, those strips can swallow a lot of lots. That's why they belong in your numbers before you make an offer, not after.

What is an asset protection zone?

The NSW Rural Fire Service (RFS) describes an APZ as a fuel-reduced gap between buildings and bushfire hazards. It reduces the risk of flames touching the house, of intense radiant heat and of ember attack. Roads can count as part of it, as can yards and gardens kept to the right standard.

For houses, the rule is about heat. Planning for Bush Fire Protection 2019 (PBP 2019) says a new house shouldn't be hit by more than 29 kilowatts per square metre of radiant heat. The tables give the distance that keeps the heat under that line.

Two more rules matter for a developer. A subdivision's APZs must sit wholly inside the development site. And they must be kept up forever, so someone has to own and look after them.

What are the IPA and OPA?

In forest, an APZ can be split into two parts.

• The Inner Protection Area (IPA) is closest to the house. Think mown lawn and tidy garden. Tree canopy should cover less than 15% of it when the trees are grown, grass should be kept to about 100 mm, and shrubs should cover no more than 10% of the ground.
• The Outer Protection Area (OPA) sits between the IPA and the bush. Some trees stay, but canopy cover should be under 30%, shrubs no more than 20% of the ground cover, and grass mown short. It slows a fire down before it reaches the IPA.

OPAs only apply in forest. For subdivisions in the highest fire weather areas, PBP 2019 lets 10 to 25 metres of the APZ be OPA, depending on slope. That helps, because some trees can stay in an OPA.

How wide does an APZ need to be?

You work it out in four steps, following Appendix 1 of PBP 2019:

1. Work out the type of vegetation in every direction, out to 140 metres.
2. Work out the effective slope, out to 100 metres.
3. Find your council area's fire weather number, called the Forest Fire Danger Index (FFDI).
4. Read the width off the right table.

Most of NSW uses FFDI 80. Greater Sydney, the Greater Hunter, the Illawarra, the Far South Coast and the Southern Ranges use FFDI 100, which means wider zones. The RFS website lists which applies to each council.

Here are some of the widths for residential subdivision in FFDI 100 areas, from Table A1.12.2. The slope columns are for land that falls away from the house down towards the bush.

In FFDI 80 areas (Table A1.12.3) the forest widths drop to 20, 25, 31, 39 and 48 metres across the same slopes. Grassland drops to 10, 11, 12, 14 and 16 metres. The full tables also cover short heath, arid shrublands and freshwater wetlands, which need less.

Why do vegetation and slope change the width so much?

Vegetation is the fuel. A forest has heavy fuel on the ground, in the shrubs and up in the canopy, so it burns hotter and longer than grass. More heat means you need more distance.

Slope changes how fast and hard the fire runs. Fire races uphill. If the land under the bush slopes down away from the house, a fire coming up that slope towards the house is faster and hotter. That's why forest needs 24 metres on flat land but 56 metres where it sits on a 15 to 20 degree slope below the house.

The slope that counts is the "effective slope", the slope of the ground under the vegetation, not the ground between the house and the bush. It's usually the steepest part. APZs themselves shouldn't be on land steeper than 18 degrees, because they're hard to maintain and clearing can make the slope unstable.

Is grassland a bushfire risk for subdivisions?

Yes. Grass fires spread fast. For a residential subdivision next to grassland, PBP 2019 says it won't be supported if the houses would be at BAL-40 or BAL-FZ, the two highest bushfire attack levels. The grassland rows in the tables give the APZ that keeps houses below that. A paddock next door can mean a 10 to 17 metre strip on your side of the fence.

Why does our report start at 35 m from bushland and 10 m from creeks?

A first look at a site doesn't know what the vegetation types are, how steep the land under them is, or which way a fire would come. So our report starts with two simple widths, on land the council's map shows as bush fire prone:

• 35 metres from kept bushland, meaning land on the Biodiversity Values Map that stays in place. That sits in the middle of the forest range for FFDI 100 areas. It's a bit under the 36 metres the table gives for forest on a 5 to 10 degree slope.
• 10 metres from creek corridors. Creek corridors are meant to be planted with native vegetation, and PBP 2019 says subdivisions have to plan for that new growth. Ten metres matches the narrowest widths in the FFDI 100 table for lighter vegetation, like grassland or forested wetland on flat land.

These are placeholders. You can change them, and a bushfire consultant sets the real widths by doing the steps above for every edge of the site. Our report starts the bushfire assessment at $8,000 to $20,000, but get quotes.

On the sample site our report uses, Ridgeback Creek (demo), the buffers take 1.7 hectares after the creek corridors, flood land, mapped bushland and steep land have already come off. The site is made up, but that's what our engine gives for it. Change 35 metres to 56 metres, which the table needs for forest on the steepest slopes, and the buffers grow. That's why the width is worth checking early. Our free lot yield calculator lets you try different areas.

When does bushfire come up in a rezoning?

Early. When a planning proposal affects bush fire prone land, the council has to consult the RFS. PBP 2019 asks for a Strategic Bush Fire Study and, for housing, an indicative layout that shows the APZs fit on the site and the roads can handle people leaving in a fire. If those issues can't be solved, the RFS won't support it. Our guide to the planning proposal process shows where this fits.

Later, a subdivision on bush fire prone land needs a bush fire safety authority from the RFS. For three or more lots, PBP 2019 also expects a perimeter road between the lots and the bush, and more than one way in and out.

Which version of the rules applies?

PBP 2019 came into force on 1 March 2020. An addendum dated November 2022 took effect on 1 May 2023 to line PBP up with the National Construction Code 2022. It mainly deals with hospitals, schools, child care and aged care, and it left the subdivision tables alone. A January 2025 addendum deals with schools, and its start date is tied to a change in the planning regulation.

A draft PBP 2026 was on exhibition from 6 August to 3 September 2026. The RFS says it can't be used or relied on until it is published and recognised in law, and that it will change after feedback. When we checked on 18 October 2026, PBP 2019 was still the version in force. If the new version lands while you're working on a site, ask your bushfire consultant which one your application falls under.

Sources: Planning for Bush Fire Protection 2019 (NSW RFS, November 2019, in force 1 March 2020), section 3.2, chapters 4 and 5, Appendix 1 Tables A1.12.2 to A1.12.4, Appendix 4; Planning for Bush Fire Protection Addendum November 2022 (NSW RFS, effective 1 May 2023); Addendum to Planning for Bush Fire Protection January 2025 (NSW RFS); Planning for Bush Fire Protection (NSW RFS, checked 18 October 2026); Building in a bush fire area (NSW RFS, checked 18 October 2026).