Patios, pergolas, decks and sheds: when a building permit is triggered

Floor height, roof, area, proximity to boundaries and whether it is attached to the house all change the answer. Work out what your project needs before you buy materials for something you cannot legally build.

⏱ 45 minIntermediate🔗 11 resources (11 free)

Almost every renovation reaches a point where someone says “it’s just a patio”. It is not just a patio. In Western Australia a roofed outdoor structure is a Class 10a building, and getting it approved involves up to four separate questions that people routinely collapse into one.

The four questions are: does it need development approval from your council’s planning side; does it need a building permit from your council’s building side; who is legally allowed to build it; and is home indemnity insurance in play. They have different thresholds, different legislation and different answers. On 1 July 2026 one of those thresholds moved, and a lot of published advice has not caught up.

If you are renovating, add a fifth: what is the status of the structures already on your block? A previous owner’s unpermitted patio does not quietly disappear. It shows up when you apply for something new, and it shows up at sale.

What a professional does at this stage

A landscaper pricing a structure works the questions in a fixed order, because they determine each other.

First they fix the estimated value of the building work. That single number drives the application fee, the Building Services Levy, whether a registered contractor is required, whether owner-builder approval is required, and whether the training levy applies. Understating it to save fees is a false economy: the permit authority determines the value, not you.

Then they resolve planning before building. A building permit cannot be granted until any development approval required under the Planning and Development Act is in hand. Lodging them the wrong way round wastes weeks.

Then they check the exemptions in the Regulations rather than in a brochure — and where the answer is marginal, they get the council’s position in writing. An email from a building surveyor is worth more than a remembered phone call when the neighbour complains eighteen months later.

Question 1: does it need development approval?

Clause 61 of the deemed provisions says development approval is not required for a patio, pergola, verandah, deck, garage, carport, outbuilding or boundary wall on the same lot as a single house — provided the R-Codes apply, the works comply with the deemed-to-comply provisions, and the site is not heritage-protected.

So the R-Codes numbers are not a design guide. They are the exemption. Miss one and you are making a development application. For a standard suburban block using Part B:

Element	Deemed-to-comply
Small outbuilding	One per dwelling site, max two boundary walls, 10 m² max, wall height 2.7 m max, not in the street setback area
Large or multiple outbuildings	60 m² or 10% of site area in aggregate, whichever is lesser; wall height 2.4 m; ridge height 4.2 m; setbacks per Table 2a
Patio, verandah or carport near a boundary	Setback may go to nil to the posts if the structure is no more than 10 m long and 2.7 m high, sits behind the primary street setback, and the eaves, gutters and roof are set back at least 450 mm from the boundary
Patio counting as open space	Only if it is no more than 0.5 m above natural ground, unenclosed on at least two sides, and covers no more than 10% of the site area or 50 m², whichever is lesser

That 450 mm gutter setback is the one that catches renovators. People build to the fence, put the gutter over it, and discover they have a development application and an unhappy neighbour.

Your council can also modify the outbuilding and street setback clauses through a local planning policy without state approval, so read the policy as well as the code. The R-Codes lesson covers how to find both.

Question 2: does it need a building permit?

Different Act, different list. Schedule 4 of the Building Regulations 2012 is the complete set of exemptions, and for a suburban garden it is short:

A freestanding Class 10a building of 10 m² or less and 2.4 m or less in height
A pergola associated with a house, 2.4 m or less high, covering 20 m² or less
A retaining wall retaining 0.5 m or less that is not associated with other building work
A fence built under a local law, or where there is no local law, masonry to 0.75 m or other materials to 1.8 m
A water tank of 5,000 litres or less

Three traps live in that list.

“Pergola” is defined narrowly. In the Building Regulations a pergola is an open structure that does not have a roof, but may have a covering of open weave permeable material. In the R-Codes, a pergola may have operable louvred roofing. So a louvred-roof structure can be a pergola for planning and a patio for building — planning-exempt and permit-required at the same time. Anything sheeted in Colorbond or polycarbonate is a patio. It gets no exemption at any size.

“Freestanding” means freestanding. A 9 m² storeroom bolted to the house is not covered by the 10 m² exemption.

Decks are not on the list at all. Treat every deck as requiring a permit unless your council tells you otherwise in writing. Councils publish their own triggers — height over 500 mm, area over 20 m², proximity to a boundary — and they are not identical.

Everything else needs a permit. For a Class 1a or Class 10 building you may lodge an uncertified application (BA2) and let the council’s building surveyor assess it, or a certified application (BA1) with a certificate of design compliance you have paid a private building surveyor to produce. Uncertified costs 0.32% of the estimated value; certified costs 0.19%; the minimum is $121 either way. Add the Building Services Levy — $61.65 for work of $45,000 or less, 0.137% above that — and, if the whole project exceeds $100,000, the 0.2% Construction Training Fund levy, payable before you start. Allow 25 business days for a decision; the permit lapses after two years unless it says otherwise.

Building without a permit is an offence under section 9 of the Building Act carrying a $50,000 fine for a first offence. Fixing it afterwards means applying for a building approval certificate for unauthorised work at 0.38% of the value — double the certified permit fee — and the council can refuse, in which case the structure comes down.

Question 3: who is legally allowed to build it

This is where the 1 July 2026 change lands, and it is narrower than the headlines suggest.

Question	Threshold	Answer for a $30,000 patio
Registered building contractor required?	Class 10a: $50,000 or more. All other building work: $20,000 or more	No — since 1 July 2026
Owner-builder approval required?	Permit required and value over $20,000 — but not for Class 10a under $50,000	No
Building permit required?	Unchanged by the reform	Yes
Home indemnity insurance required?	Associated work alone — pool, carport, fence, pergola, landscaping — is excluded even over $20,000	No

Read the second row carefully. The exemption is for Class 10a work. Enclose that patio into a studio and it stops being Class 10a, the $20,000 threshold returns, and you need either a registered contractor or Building Services Board owner-builder approval — which takes about six weeks and is generally available only once every six years.

Read the fourth row carefully in the other direction. Home indemnity insurance is excluded for standalone landscape structures, but if your patio sits inside a single contract for a house renovation over $20,000, the insurance applies.

Bushfire, and the safety you cannot delegate

Check your address on the DFES bush fire prone areas map before you design. If your block is in a designated area, a Class 10a building or deck sited less than 6 metres from the house attracts bushfire construction requirements and the BAL must be provided with the application. That changes materials, detailing and price. The bushfire lesson goes further.

Three hazards on this work are serious enough to name plainly:

Asbestos. Patio roofs, eaves and shed walls built before about 1990 should be assumed to contain it. More than 10 m² of non-friable material, or any friable material, is licensed removal work.
Overhead powerlines. Carports and patios near the front boundary sit under service cables. Assume nothing about clearances; contact Western Power before lifting anything long into that space.
Electrical work. No permit exemption and no registration change makes it legal for you to run a circuit to a new structure. That is a licensed electrician, always.

Trench collapse, silica dust from cutting footings into limestone, and working alone at height in a Perth summer are covered in site establishment and safety.

Existing structures with no paperwork

Every unpermitted structure you inherited is either regularised or removed. Ask the council for the property’s building records early — before you design around a patio that may not be allowed to stay. Carry the outcome back into your garden audit as a KEEP, REPLACE or REMOVE with a cost against it.

What happens to this next

You now have, for every structure in your concept: whether it needs development approval, whether it needs a building permit, which application type, who may build it, and the fees and levies attached. Those fees are real money and belong in the budget alongside materials — quantity take-offs will ask for them, and structures, pergolas and screens assumes the approval is already in your hand.

The next lesson does the same job for pools and pool fencing, where the barrier requirements are stricter, the inspection regime is ongoing, and the consequences of getting it wrong are not financial.

Checklist

List every structure in your concept and its dimensions
Check each against the exemptions in the Building Regulations and your council
Confirm bushfire (BAL) requirements if your block is in a designated area
Allow realistic time in your programme for approvals

Where to go deeper

Every link below was fetched and checked before it shipped. Nothing here is a guess.

Freegovernment20 minPerth / WA
Building or renovating your home — Class 10a builder registration threshold Q&As
Building and Energy, Department of Local Government, Industry Regulation and Safety
Why this oneThe regulator's own plain-English answer to the 1 July 2026 change, and the only page that states all three consequences together. It confirms that Class 10a buildings valued at less than $50,000 no longer need a registered building contractor, that patios count as Class 10a in WA, and that a homeowner can build one themselves without owner-builder approval. It also states clearly that building permit requirements are unchanged, which is the part people get wrong.
Link checked 2 Aug 2026
Freegovernment10 minPerth / WA
Builders' registration
Building and Energy, Department of Local Government, Industry Regulation and Safety
Why this oneThe current statement of both registration thresholds in one place: $50,000 or more for Class 10a buildings, $20,000 or more for all other building work, and only where a building permit is required and the work is in the Building Services Board's prescribed area. Registration sits under the Building Services (Registration) Act 2011, not the Building Act, which is why it is a genuinely separate question from your permit.
Link checked 2 Aug 2026
Freegovernment20 minPerth / WA
Building approvals — forms, fees and building classifications
Building and Energy, Department of Local Government, Industry Regulation and Safety
Why this oneWhere the BA1 (certified) and BA2 (uncertified) application forms live, plus the current fee tables you need to budget the approval itself. It publishes the Building Services Levy rates — $61.65 flat for work of $45,000 or less, 0.137% above that, and double for unauthorised work — and the Building Act application fees. It also gives the NCC classification definitions, which is how you work out whether your structure is Class 10a at all.
Link checked 2 Aug 2026
Freegovernment30 minPerth / WA
Building Regulations 2012 (WA) — Schedule 4
Parliamentary Counsel's Office / WA Legislation
Why this oneThe actual, legally operative list of building work that does not require a building permit. Schedule 4 clause 2 is short and readable, and it is the only place the exemptions are stated exactly — including the statutory definition of a pergola, which is narrower than the one used in planning. Read the Schedule rather than a council summary of it, then use the council summary to interpret.
Change this for Perth
Check the currency date at the top of the page before relying on it. The version consulted for this lesson was 04-ae0-01, current at 23 July 2026. Schedule 4 clause 1 also exempts whole rural local government districts, none of which are in Perth or Peel.
Link checked 2 Aug 2026
Freestandard60 min for the relevant clausesPerth / WA
Residential Design Codes Volume 1 (April 2026)
Western Australian Planning Commission / Department of Planning, Lands and Heritage
Why this oneThe deemed-to-comply numbers that decide whether you need development approval. For a suburban single house read Part B: clause 5.1.3 for lot boundary setbacks (including the nil-setback allowance for patios and carports), 5.4.3 for outbuildings, and the definitions of patio, pergola, building and open space in Appendix A1. Version 3, published 10 April 2026, is the current one.
Change this for Perth
Part B applies to single houses coded R40 and below and grouped dwellings R25 and below; denser codings use Part C, which has different outbuilding numbers. Your local government can also modify the outbuilding and street setback clauses through a local planning policy without state approval, so check the policy as well as the code.
Link checked 2 Aug 2026
Freegovernment20 minPerth / WA
Planning and Development (Local Planning Schemes) Regulations 2015 — Schedule 2 clause 61
Parliamentary Counsel's Office / WA Legislation
Why this oneClause 61 of the deemed provisions is the table that says when development approval is not required. Item 7 covers outbuildings, patios, pergolas, verandahs, decks, garages, carports and boundary walls on the same lot as a single house — exempt if the R-Codes apply, the works comply with the deemed-to-comply provisions, and the site is not heritage-protected. Item 1 does the same for demolishing them.
Link checked 2 Aug 2026
Freegovernment15 minPerth / WA
Home indemnity insurance fact sheet
Building and Energy, Department of Local Government, Industry Regulation and Safety
Why this oneSettles the question people most often get wrong about landscape structures. The fact sheet states that where the work is associated work alone — a swimming pool, carport, fence, pergola or landscaping under a separate contract — home indemnity insurance is not required even if the work is over $20,000. It also sets out the cover limits ($200,000 for defective work, $40,000 for deposit) and the owner-builder trap of selling within seven years.
Link checked 2 Aug 2026
Freegovernment15 minPerth / WA
Owner-builder approval
Building Services Board / Building and Energy
Why this oneIf your structure is not Class 10a — an enclosed studio, a habitable conversion, an extension — and the value exceeds $20,000, you cannot simply put your own name on the permit. This page sets out the Building Services Board approval you need first, the once-every-six-years limit, and the evidence required including a white card. Allow roughly six weeks; it is the approval most likely to blow out a programme.
Link checked 2 Aug 2026
Freetool5 min for your addressPerth / WA
View a map of bush fire prone areas
Department of Fire and Emergency Services (DFES)
Why this oneThe free, official viewer for the designated bush fire prone area map, which is the switch that turns on AS 3959 construction requirements for a shed, patio or deck near your house. Type in your address before you design anything, because BAL-rated construction changes materials, detailing and cost, and it changes what your building surveyor will certify.
Change this for Perth
Designation is by the FES Commissioner and the map is reissued periodically, so check it again if your project spans a year or more. Being in the mapped area is the trigger; the BAL rating itself is determined for your specific building site.
Link checked 2 Aug 2026
Freegovernment10 minPerth / WA
An introduction to the CTF Levy
Construction Training Fund
Why this oneThe training levy is a real line in your approval budget and the threshold has just moved. This page confirms the rate is 0.2% of the estimated value of construction and that from 1 July 2026 the threshold rose from $20,000 to $100,000, which takes most single-structure landscape jobs out of it entirely. It also confirms the levy is payable before construction starts whether or not a permit is required, and that soft landscaping is excluded.
Change this for Perth
The old $20,000 threshold still applies where construction commenced before 1 July 2026, and some wa.gov.au pages had not been updated when this was checked. Work out your total project value, not just the structure, before you assume you are under.
Link checked 2 Aug 2026
Freearticle10 minPerth / WA
Decks — approvals guide
City of Joondalup
Why this oneA worked example of how one Perth local government actually applies the rules to decks, which is useful because decks are the structure the Building Regulations exemptions do not mention. Joondalup publishes its triggers plainly — over 20 square metres, higher than 500 mm, closer than 900 mm to a boundary, in a bushfire prone area, or with privacy screens — plus the 7.5 metre privacy screen rule that catches raised decks.
Change this for Perth
This is one council's interpretation and its own thresholds, not state law. Use it to understand the shape of the question, then get your own council's answer in writing before you build.
Link checked 2 Aug 2026

The rules, with sources

WA regulation changes. Each point below names its primary source and the date it was last checked — always confirm with your own council before you build.

A person must not do building work unless a building permit is in effect for it or the work is exempt. The penalty is a fine of $50,000 for a first offence, $75,000 for a second, and $100,000 plus 12 months imprisonment for a third or subsequent offence.
Building Act 2011 (WA) section 9 ↗ · checked 2 Aug 2026
From 1 July 2026, construction of a Class 10a building — a shed, carport, private garage, patio or the like — valued at less than $50,000 does not have to be carried out by a registered building contractor in Western Australia. The threshold was previously $20,000 and remains $20,000 for all other building work. Building permit requirements are unchanged.
Building and Energy, Department of Local Government, Industry Regulation and Safety ↗ · checked 2 Aug 2026
A homeowner can build a Class 10a building themselves without obtaining owner-builder approval if the work is valued at less than $50,000. Owner-builder approval is otherwise required where a building permit is required and the estimated value of the building work exceeds $20,000, and an owner-builder can generally only be granted a building permit once every six years.
Building and Energy / Building Services Board ↗ · checked 2 Aug 2026
Home indemnity insurance is not required where the work is associated work performed alone under a separate contract — such as a swimming pool, carport, fence, pergola or landscaping — even if the work is over $20,000. It is also not required where a building permit is not required.
Home indemnity insurance fact sheet, Building and Energy ↗ · checked 2 Aug 2026
A building permit is not required for: a freestanding Class 10a building with a floor area not exceeding 10 square metres and no more than 2.4 metres in height; a pergola associated with a Class 1 building no more than 2.4 metres high covering no more than 20 square metres; a retaining wall retaining ground no more than 0.5 metres high and not associated with other building work; a fence built under a local law, or where there is no local law, masonry no more than 0.75 metres high or other materials no more than 1.8 metres high; and a water storage tank of 5,000 litres or less. All are conditional on the site not being in wind region C or D as defined in AS 1170.2.
Building Regulations 2012 (WA) Schedule 4 clause 2 ↗ · checked 2 Aug 2026
For the purposes of the building permit exemption, a pergola means an open structure that does not have a roof but may have a covering of open weave permeable material.
Building Regulations 2012 (WA) Schedule 4 clause 2 ↗ · checked 2 Aug 2026
Development approval is not required for the erection of, or alterations or additions to, an outbuilding, patio, pergola, verandah, deck, garage, carport or boundary wall or fence on the same lot as a single house or grouped dwelling, provided the R-Codes apply, the works comply with the deemed-to-comply provisions of the R-Codes, and the works are not located in a heritage-protected place.
Planning and Development (Local Planning Schemes) Regulations 2015 Schedule 2 clause 61, item 7 ↗ · checked 2 Aug 2026
Under R-Codes Volume 1 Part B clause 5.4.3, a small outbuilding is deemed to comply if there is no more than one per dwelling site, it has no more than two boundary walls, it does not exceed 10 square metres in area or a wall height of 2.7 metres, and it is not in the primary or secondary street setback area. Large and multiple outbuildings must not exceed 60 square metres or 10 per cent of the site area in aggregate, whichever is lesser, a wall height of 2.4 metres and a ridge height of 4.2 metres.
Residential Design Codes Volume 1, Version 3, 10 April 2026 ↗ · checked 2 Aug 2026
Under R-Codes Volume 1 Part B clause 5.1.3, lot boundary setbacks for carports, patios, verandahs or equivalent structures may be reduced to nil to the posts where the structure is not more than 10 metres in length and 2.7 metres in height, is located behind the primary street setback, and has eaves, gutters and roofs set back at least 450 mm from the lot boundary.
Residential Design Codes Volume 1, Version 3, 10 April 2026 ↗ · checked 2 Aug 2026
In a designated bushfire prone area, bushfire performance requirements apply to a Class 10a building or deck that is, or is proposed to be, located less than 6 metres from a Class 1, Class 2, Class 3 or Class 9 vulnerable use building, and the BAL for the building site must be provided with the application.
Building Regulations 2012 (WA) regulation 18A ↗ · checked 2 Aug 2026
Building permit application fees from 1 July 2026 are 0.32% of the estimated value for an uncertified application and 0.19% for a certified application for a Class 1 or Class 10 building, in each case not less than $121.00. An application for a building approval certificate for a structure on which unauthorised work has been done costs 0.38% of the estimated value of that work, not less than $121.00.
Building Regulations 2012 (WA) Schedule 2, as inserted by SL 2026/95 ↗ · checked 2 Aug 2026
The Construction Training Fund levy is 0.2% of the estimated value of construction. From 1 July 2026 the value threshold rose from $20,000 to $100,000, and the levy must be paid by the project owner before construction commences whether or not a permit is required. Soft landscaping is excluded.
Construction Training Fund ↗ · checked 2 Aug 2026
The responsible person named on a building permit must give a notice of completion to the permit authority within 7 days of completing the work, with a penalty of $10,000. A building permit has effect for 2 years from the day it is granted unless the permit sets out a different period or an extension is approved.
Building Act 2011 (WA) sections 32 and 33 ↗ · checked 2 Aug 2026