{{ propApi.closeIcon }}
Our industry
Our industry $vuetify.icons.faArrowRight
Economic research and forecasting Economics Housing outlook Tailored market research Economic reports and data Inspiring Australia's building professionals HOUSING The only place to get your industry news Media releases Member alerts Submissions See all
Business support
Business support $vuetify.icons.faArrowRight
Become an apprentice host Hire an apprentice Why host a HIA apprentice? Apprentice partner program Builder and manufacturer program Industry insurance Construction legal expenses insurance Construction works insurance Home warranty insurance Tradies and tool insurance Planning and safety services Building and planning services How can HIA Safety help you? Independent site inspections Solutions for your business Contracts Online HIA Tradepass HIA SafeScan HR Docs Trusted legal support Legal advice and guidance Professional services Industrial relations
Resources & advice
Resources & advice $vuetify.icons.faArrowRight
Building it right Building codes Australian standards Getting it right on site See all Building materials and products Concrete, bricks and walls Getting products approved Use the right products for the job See all Managing your business Dealing with contracts Handling disputes Managing your employees See all Managing your safety Falls from heights Safety rules Working with silica See all Building your business Growing your business Maintaining your business See all Other subjects COVID-19 Getting approval to build Sustainable homes
Careers & learning
Careers & learning $vuetify.icons.faArrowRight
A rewarding career Become an apprentice Apprenticeships on offer Hear what our apprentices say Advice for parents and guardians Study with us Find a course Get your builder's licence Learn with HIA
HIA community
HIA community $vuetify.icons.faArrowRight
Join HIA Sign me up How do I become a member? What's in it for me? Get involved Become an award judge Join a committee Partner with us Get to know us Our members Our people Our partners Mates rates What we do Mental health program Charitable Foundation GreenSmart
Awards & events
Awards & events $vuetify.icons.faArrowRight
Awards Australian Housing Awards Awards program National Conference Industry networking Events Building and Renovation Home Show HOMEFEST
HIA products
HIA products $vuetify.icons.faArrowRight
Shop @ HIA Digital Australian Standards Contracts Online Shipping and delivery Purchasing terms & conditions Products Building codes and standards Hard copy contracts Guides and manuals Safety and signage See all
About Contact Newsroom
$vuetify.icons.faMapMarker Set my location Use the field below to update your location
Change location
{{propApi.text}} {{region}} Change location
{{propApi.successMessage}} {{region}} Change location

$vuetify.icons.faPhone1300 650 620

Boundary walls and dividing fences in WA

In Western Australia, boundary walls have been employed as part of Class 1a (residential houses) and Class 10 (carports, garages, patios, sheds and outbuildings) buildings for many years.

The changing lot typologies across new housing estates, along with infill lots in existing suburbs, are triggering design solutions that may utilise (sometimes multiple) boundary and retaining walls.

Historically, continuing access and rights issues across adjoining properties to construct a boundary or retaining wall resulted in the Building Commission’s introduction of Form BA20 (Notice and request for consent to encroach or adversely affect) and Form BA20A (Notice and request for consent (response notice): Protection structures, party walls, removal of fences, access to land).

The associated access issues that boundary and retaining walls present are continually causing some confusion at both approvals and construction stages of building, with many checklists for Building Permit applications often requesting additional permissions from adjoining landowners prior to the assessment of a permit application.

These forms are used by owners and builders to formally seek consent from an adjoining landowner to gain access for the erection of scaffolding, access for avoiding overhand bricklaying methods, flashing, waterproofing, soil stabilisation, retaining wall maintenance, surveys etc – essentially any works that is shown to affect or encroach on an adjoining land for the purposes of construction and/or maintenance purposes.

Updated BA20 and BA20A forms

Building and Energy have recently updated the BA20 and BA20A forms, for work affecting other land, at the request of HIA and the wider industry in general.

A welcome and specific change is the addition of an advice note at Part 4 of the BA20A form, providing greater clarity where consent or a court order is not required for the removal of fences.

Other changes in the updated forms provide additional guidance for owners of affected land and general wording improvements in the forms.

What’s the difference between the two forms?

Form BA20

A completed Form BA20 demonstrates consent by an adjoining property owner for the subject works of a building or demolition permit to either encroach or adversely affect the adjoining property.

An application for a building permit will highlight this encroachment, and the completed form BA20 will likely be required prior to the issuance of a building permit.

It may also be necessary to secure a signed BA20 from an adjoining property owner after a permit is issued; for example, demolition or excavation works may expose the need to encroach on neighbouring land, or adversely affect the land with the removal of trees and retaining walls etc.

Form BA20A

A completed form BA20A demonstrates consent by an adjoining property owner for the subject works of a building or demolition permit to access adjoin properties, beyond the boundaries of the subject land, to conduct surveys (unless vacant) or work to party walls, place a protection structure (such as scaffolding or barriers) to remove a fence/gate, underpinning works etc.

What’s the issue?

A form BA20A notes ‘some circumstances’ where consent is not required per Section 80(1)(d) of the Building Act 2011 – these circumstances can be overlooked when boundary or retaining walls, and even brick fences, are proposed as part of a building permit.

The title for a BA20A (Protection structures, party walls, removal of fences, access to land) is easily read that this form is to be used for all matters relating to those outlined – including any buildings or works that may trigger the need to remove a fence (such as a boundary or retaining wall).

However, Section 80(1)(d) is very clear and informs when a BA20A is not required to remove a fence (either on, or beyond, the boundaries of the proposed works), being;

“… (i) the removal is required for a close wall;

(ii) a building permit for the close wall is in effect;

(iii) the person responsible for the work has given at least 7 business days’ notice …”

The exemptions listed at 80(1)(d) are not able to be applied in isolation of each other and/or at the exclusion of each other.

The definition of a ‘close wall’ at Section 80(2A) of the Building Act 2011 is;

“… a wall, fence, post or column, whether free-standing or attached to, or forming part of, a building or structure, that is so close to a boundary of the land on which the wall or fence is located that it is not reasonably practicable to build a separate dividing fence along the boundary …”

The construction of a boundary or retaining wall (as commonly referred) would meet this definition of a ‘close wall’ at Section 80(2A) – and with a valid building permit in place, Section 80(1)(d) may be applied for a boundary or retaining wall in the absence of other considerations.

It may also be applied to a brick fence if a valid building permit covers such.

What else do I have to consider?

This information sheet only pertains to the requirements and exemptions listed under Section 80 of the Building Act 2011.

There may be a Local Planning Policy, Local Authority control or other legislation that limits (or does not exempt) the removal of fences for the construction of what would otherwise be defined as a ‘close wall’. Any proposal for such must be further investigated with the relevant Local Government and against other relevant legislation.

The exemptions at Section 80(1)(d) of need for consent to remove a fence (as a BA20A would otherwise require) does not exempt a person responsible for constructing a ‘close wall’ to provide notice to the adjoining landowner (per Section 80(1)(d)(iii)) of the timeframes surrounding fence removal, construction and/or any replacement schedule.

While the Building Act 2011 is silent on the issue, the definition of a ‘close wall’ provided at Section 80(2A) does not necessarily mean that a boundary or retaining wall (when replacing a fence in location) actually forms a dividing fence itself.

It would be prudent of a person responsible for constructing a ‘close wall’ that is subject to consent exemptions at Section 80(1)(d) to remove as little fence as practically possible in order to necessitate construction; and it may also be a requirement of any other policy, control or legislation to do so.

To find out more, contact HIA’s Building Services team.

Email us

Share with your network:

More articles on:

{{ tag.label }} {{ tag.label }} $vuetify.icons.faTimes
Find guides, how-tos, resources and more

Managing your business


Can’t find what you need, check out other resources that might be closer to the mark.

Explore resources

Carports & Pergolas - Design & Construction Manual

This construction manual is suitable for any design and construction work with timber carports and pergolas. It contains clear and concise information...

Hancock's Roof Cuts & Rafter Lengths

Hancock’s Roof Lengths and Rafter Lengths is well known throughout the building industry as the Little Red Roofing Book. No self-respecting roofer sho...

Pocket Span Table Book

The Pocket Span Table Book comes in an easy-to-carry, pocket-sized (A5), durable book in a spiral-bound format. It includes span tables for commonly u...

Timber Decks Design and Construction Manual

The Timber Decks Design and Construction Manual is an illustrated guide to the design and construction of low-maintenance timber decks for domestic ap...