Common Boundaries Regulation 2024

Compliant fence: defined in section 3(2) as a fence that complies with all the swimming pool safety requirements each party to the application for a determination must comply with. This is a conjunctive definition: it requires the fence to meet the highest standard applicable to any party. If one neighbour has a regulated pool and the other does not, the compliant fence must satisfy the pool-owning neighbour’s obligations. If both have pools but with different exemptions, the fence must meet the stricter of the two sets of requirements. The cost of a compliant fence is the baseline against which the cost of a non-compliant fence is compared under section 3(1)(b).

Party with a greater extent of compliance: not defined directly, but section 3(1)(c)(i)-(iv) and the examples identify two scenarios. First, the party who must maintain a safety barrier for a regulated swimming pool on their land, when the other party has no such pool. Second, the party who must maintain a safety barrier when the other party has been granted a ministerial exemption or benefits from a standing exemption for a pool on their land. In essence, the party with the stricter legal obligation to maintain a pool safety barrier is the one with a greater compliance burden. This concept is key to cost adjustment.

Regulated swimming pool, safety barrier, ministerial exemption, and standing exemption: all defined by cross-reference to the Building Act 2004. The regulation does not restate those definitions, so practitioners must consult the Building Act. A regulated swimming pool is one to which Part 5A of the Building Act applies, generally any pool capable of being filled with water to a depth of more than 300 millimetres, including spas. A safety barrier is a fence, wall, or other structure that restricts access to the pool to prevent drowning, especially of young children. A ministerial exemption is granted under Building Act section 83(1) and may relieve a pool owner from some or all safety barrier requirements. A standing exemption is automatic for certain pools, such as those constructed before a certain date or those already covered by other safety provisions. The regulation specifically references these distinctions to capture cases where one party’s compliance burden is reduced by exemption, making them less disadvantaged than the pool-owning party without an exemption.

Determination types: the regulation categorises ACAT determinations under four heads: (i) under Act section 10(2)(d) - cost contribution for erecting a fence where one party is the erecting party; (ii) under Act sections 11(3)(e) or 12(3)(a) - proportion of repair or replacement costs; (iii) under Act sections 12(2) or 13(2) - whether the non-applicant should contribute to the applicant’s cost of erecting, repairing, or replacing; (iv) under Act section 13(3)(a) where the circumstance in section 13(4)(b) applies - adjustment of the amount for the same reasons. Each type triggers a slightly different cost-adjustment question: for some, the regulation asks whether the amount should be adjusted; for others, whether one party should bear a greater proportion; for others, whether it is reasonable to require contribution at all.

The role of ACAT: ACAT is the tribunal that hears disputes under the Common Boundaries Act when neighbours cannot agree on fence proposals, costs, or contributions. The regulation does not confer new jurisdictional power; it only directs how ACAT must exercise existing powers when the application involves a dividing fence that is also a safety barrier for a regulated swimming pool.

Neighbours with shared fences and at least one regulated swimming pool: This is the primary group. The regulation only applies where a dividing fence (the boundary fence between two parcels of land) also functions as a safety barrier for a regulated swimming pool. That typically means one neighbour has a pool, and the fence between them forms part of the safety barrier required by the Building Act. The regulation affects both the pool-owning neighbour (who must comply with pool safety requirements) and the neighbour without a pool (who may be asked to contribute to a more expensive fence than they otherwise would need). The regulation potentially shifts the cost burden away from the pool owner and onto the non-pool neighbour if the tribunal decides it is reasonable. Conversely, it may protect the non-pool neighbour from being forced to pay for upgrades they do not need, if the pool owner is the one with the greater compliance obligation.

Occupiers who request a fence under Division 2.1 of the Act: The regulation applies to any application under that division. Any occupier who initiates proceedings for a new fence, or for repair or replacement of an existing fence, and who has a pool on their land, will be subject to these additional factors. Similarly, if the non-applicant neighbour has a pool, the tribunal must consider the compliance disparity.

ACAT members and registrars: They must now apply the regulation in any relevant proceeding. This adds a procedural and analytical step. Tribunal members will need to understand the Building Act definitions, determine which party has a greater compliance burden, and decide whether adjusting costs is appropriate. This increases the complexity of what was often a relatively straightforward fencing dispute. It may also increase the need for expert evidence about pool safety compliance and fence costs, especially if the parties disagree.

Property conveyancers and real estate agents: The regulation does not directly regulate them, but they may need to advise clients about potential future fencing disputes when a property with a pool adjoins a property without a pool. The cost allocation risk may affect property valuations or negotiations. A buyer of a pool-side property might face a future fencing dispute where their neighbour argues they should not pay extra for a compliant fence. Conversely, a buyer of a non-pool property next to a pool might face a demand to contribute to a more expensive fence.

Fencing contractors and builders: They will need to quote for fences that comply with both the Common Boundaries Act (as to location and type) and the Building Act safety barrier requirements. The regulation does not impose direct obligations on them, but the cost differential between a compliant and non-compliant fence (section 3(1)(b)) becomes a central factual issue. Contractors may be called to give evidence in ACAT proceedings about those costs.

ACT Government agencies: The regulation affects the ACT Planning and Land Authority and the Building Act regulator indirectly, as they administer the pool safety regime. The regulation creates an additional intersection between two regulatory systems: fencing law and pool safety law. The ACT Government may also face increased ACAT workload as parties argue over cost adjustments.

People renting: Tenants are occupiers and can apply for fence orders under the Act. If a tenant with a pool faces a fencing dispute with a neighbour, the regulation applies. However, the tenant may not be the party ultimately responsible for compliance with pool safety requirements (that may be the landlord). The regulation does not address this distinction; it only asks about the party’s compliance obligation, which may be uncertain in a tenancy.

Duty on ACAT: The only duty created by the regulation is on ACAT. Under section 3(1), ACAT must take into account the listed matters in making a determination under Division 2.1 of the Act. This is mandatory language: “must take into account”. Failure to do so would likely be an error of law, giving grounds for appeal or review. The duty applies to each determination type listed in subparagraphs (c)(i)-(iv), but only when the cost of a compliant fence exceeds the cost of a non-compliant fence. If the costs are equal, subparagraph (c) does not apply, and ACAT need not consider adjustments - but it still must consider subparagraphs (a) and (b) (whether parties must comply with pool safety requirements, and the cost differential). So the duty to consider the cost adjustment only arises after the threshold of higher cost is met.

Right of a party to argue for cost adjustment: The regulation does not create a new right, but it gives parties a statutory basis to argue that the usual equal sharing should be departed from. A pool-owning applicant can argue that because they bear a greater compliance burden, the non-applicant should contribute a larger share (or that it is reasonable to require contribution at all). Conversely, a non-pool applicant can argue that because the other party has a greater compliance burden, the cost should be adjusted in their favour. The regulation does not say who bears the burden of proof on these issues; that will be determined by ACAT practice and the general law on cost and contribution.

Right to an adjusted amount: The regulation contemplates that ACAT may adjust the amount contributed by a party (subparagraphs (i) and (iv)), may adjust the proportion borne (subparagraph (ii)), or may determine whether it is reasonable to require any contribution at all (subparagraph (iii)). These outcomes are discretionary; the regulation does not mandate a particular adjustment, only that ACAT must consider whether an adjustment is appropriate.

No new duty on neighbours: The regulation does not itself require any neighbour to install a safety barrier or comply with pool safety requirements. Those duties arise under the Building Act, not this regulation. The regulation only comes into play if the fence is also a safety barrier. If a fence is not used as a safety barrier (e.g., because the pool has a separate barrier or is exempt), the regulation does not apply.

Interaction with the Act’s existing cost-sharing provisions: The Common Boundaries Act generally presumes equal contribution for fences that serve both properties equally. But the regulation overrides that presumption by directing ACAT to consider a disproportionate compliance burden. It does not, however, completely displace equal sharing; it only adds a factor. The tribunal must still apply the Act’s provisions and may decide that equal sharing remains appropriate despite the disparity.

No duty on the parties to provide information: The regulation does not require parties to disclose their pool compliance status or costs. However, in proceedings, a party seeking adjustment would ordinarily need to adduce evidence of the compliance disparity and the cost differential. ACAT has power to make orders for discovery or exchange of information under its procedural rules, but the regulation does not create any additional disclosure obligation.

The regulation itself imposes no penalties and creates no offences. It is purely procedural. Enforcement of any non-compliance with the regulation would be through appeal or judicial review of an ACAT determination, not through any separate penalty proceeding.

The penalty unit values noted in the republication ($160 for an individual, $810 for a corporation) apply to offences under the enabling Act or other laws, not under this regulation. The regulation does not contain any offence provisions.

If a person fails to comply with an ACAT order made after the regulation is applied, that non-compliance could lead to enforcement under the ACT Civil and Administrative Tribunal Act 2008, including possible contempt proceedings or enforcement orders. But the regulation itself is not the source of that enforcement.

The Building Act 2004 (which defines regulated swimming pools and safety barriers) contains its own penalty provisions for failure to maintain a compliant safety barrier. Those penalties are not part of this regulation, but they provide the context that makes a compliant fence more expensive and thus triggers the regulation. A pool owner who fails to maintain a safety barrier may face fines or orders under the Building Act, and that enforcement risk drives their incentive to seek a compliant fence. The regulation then determines how the cost of that compliance is shared with a neighbour.

Enforcement of the regulation in ACAT proceedings is through the tribunal’s own enforcement mechanisms. If ACAT fails to take into account the prescribed matters, a party may apply to the ACT Supreme Court for judicial review under the Administrative Decisions (Judicial Review) Act 1989 (ACT), or under the tribunal’s own review provisions. The error would be jurisdictional or legal error.

Because the regulation is new (commenced 13 September 2024), there is no enforcement history. The only practical enforcement scenario is a party challenging an ACAT decision that did not consider the regulation’s factors. Given the narrow scope, such challenges are likely to be expensive and rare.

Common Boundaries Act 1981: The regulation is made under section 13A(2) of that Act. It operates entirely within the framework of the Act. It only applies to determinations under Division 2.1 of the Act (fences requested by occupiers). It does not affect other divisions of the Act, such as fence notices (Division 2.2) or boundary line adjustments. The regulation modifies the tribunal’s decision-making but does not amend the Act’s substantive provisions. The Act’s general principles (equal sharing, reasonableness, types of orders) remain intact; the regulation adds a new mandatory consideration.

Building Act 2004, Part 5A (Regulated swimming pools): This is the most critical interaction. The regulation directly cross-references Building Act definitions: “regulated swimming pool”, “safety barrier”, “ministerial exemption”, and “standing exemption”. It also refers to “the swimming pool safety requirements” which are the requirements under Part 5A. This means that the regulation’s operation depends entirely on the Building Act’s scope and definitions. If the Building Act is amended to change the definition of a regulated swimming pool or to alter safety barrier requirements, the regulation’s effect may shift. Practitioners must therefore read the regulation together with the current Building Act.

Legislation Act 2001: The regulation is a subordinate law made under the Legislation Act. The republication notes refer to part 11.3 (editorial changes) and section 133 (penalty units). The regulation’s validity depends on compliance with the Legislation Act’s requirements for making regulations. The Act’s section 75 on commencement and section 89 on omission of spent provisions also affect the regulation’s status.

ACT Civil and Administrative Tribunal Act 2008: The regulation affects ACAT’s substantive decision-making powers but does not change ACAT’s procedures, jurisdiction, or appeal rights. ACAT must apply the regulation as part of the law it is required to apply. The regulation does not confer or remove jurisdiction.

Common law on fences and boundaries: The Common Boundaries Act largely codifies common law principles of fencing and cost sharing. The regulation introduces a statutory overlay that departs from the common law’s usual equal cost approach by mandating consideration of disproportionate pool compliance burdens. However, the common law still informs the concept of “reasonable” contribution where the regulation uses that term (e.g., in subparagraphs (iii) and (iv)).

Other ACT laws: The regulation does not interact directly with other laws like the Planning Act or the Residential Tenancies Act. But in practice, a fencing dispute may involve issues under those laws, such as planning approval for fence height or tenancy obligations for swimming pool safety. The regulation only applies to the cost-sharing aspect; it does not override planning or tenancy laws.

No interaction with Commonwealth laws: There is no federal dimension. The regulation is purely ACT law.

The Common Boundaries Regulation 2024 is a new regulation, made on 12 September 2024 and effective from 13 September 2024. Its amendment history, as shown in the republication, is empty. The regulation has not been amended since commencement. The only change noted is that section 2 (commencement) was omitted by operation of Legislation Act section 89(4) once the regulation commenced, which is a standard mechanical removal of spent provisions.

Because the regulation is so recent, any amendment history will be prospective. The regulation was made to implement section 13A(2) of the Common Boundaries Act, which appears to have been inserted or amended at some point to allow regulations to prescribe additional ACAT considerations. The regulation itself does not amend the Act; it is a standalone instrument.

The legislation history note shows the regulation was notified on the ACT legislation register on 12 September 2024, with sections 1 and 2 commencing that day, and the remainder (section 3) commencing 13 September 2024. This is a typical staged commencement.

There is no indication of any policy change or prior regulations replaced. The regulation appears to be the first of its kind under section 13A(2). If the Act is later amended to expand or restrict the regulation’s scope, the regulation would need to be updated accordingly.

Given the narrow focus, future amendments are unlikely unless the Building Act definitions change significantly or if ACAT’s application of the regulation reveals unintended consequences requiring clarification. For instance, if the regulation leads to increased litigation or confusion about what constitutes a “greater extent of compliance”, the Executive may amend the regulation to provide more detailed criteria or examples.

The regulation commenced on 13 September 2024, so there is no litigation history yet. No ACAT decisions have applied the regulation, and no court decisions have interpreted it.

However, we can anticipate likely litigation themes:

• Disputes over whether the fence is also a safety barrier: The regulation only applies if the dividing fence is a safety barrier for a regulated swimming pool. If one party argues the fence is not the safety barrier (e.g., the pool has a separate fence, or the pool is exempt), the regulation may not apply. ACAT may need to determine that threshold question.

• Disputes over which party has a “greater extent of compliance”: The examples in the regulation clarify two scenarios, but others may arise. For instance, if both neighbours have pools but one has an exemption that covers only part of the required barrier, the comparative compliance burden may be unclear. ACAT may develop case law on this.

• Disputes over the cost of a compliant fence vs a non-compliant fence: This is likely to be the key factual contest. Parties may obtain competing quotes, and ACAT will need to decide which quotes are reliable and whether the difference in cost is material. The regulation does not set a threshold for materiality.

• Appeals from ACAT decisions: A party who loses on cost allocation may argue that ACAT failed to take into account the regulation’s matters, or that it took them into account incorrectly (e.g., by giving them too much weight, or by misinterpreting a Building Act definition). The ACT Supreme Court may review such decisions under the ACT Civil and Administrative Tribunal Act.

• Interpretation of “reasonableness”: In subparagraphs (iii) and (iv), the regulation uses the term “reasonable” for requiring contribution. This invites legal argument about the criteria for reasonableness beyond the compliance disparity. ACAT will need to develop a test.

• Interaction with other ACAT decisions: ACAT may have existing decisions under the Common Boundaries Act about fencing costs where pool safety was not an issue. The regulation may create tension with those earlier precedents. How ACAT reconciles them will be significant.

Given the regulation’s youth and narrow scope, litigation is likely to be infrequent, but the first few decisions will set precedent and be closely watched by property lawyers and the ACT Government.

Cost differential threshold: The cost adjustment provisions only apply if the compliant fence is more expensive than a non-compliant fence. If they cost the same, section 3(1)(c) does not apply. However, section 3(1)(a) and (b) still apply, so ACAT must still consider compliance requirements and cost differential. But if no cost differential exists, there is no basis for adjustment. Practitioners should not assume a cost differential automatically exists. A compliant fence may be achieved by upgrading an existing fence at minimal extra cost, or a non-compliant fence may be more expensive for other reasons.

Definition of “compliant fence” is conjunctive: The fence must comply with all the swimming pool safety requirements each party must comply with. That means if one party has a ministerial exemption for some requirements, the compliant fence need only meet the requirements not exempted for that party, but still must meet all requirements of the other party (if any). This could lead to a fence that is compliant for one party but not for the other, which is then not a “compliant fence” under the definition. That seems to create an all-or-nothing approach: the fence must satisfy both parties’ minimum obligations. If one party has no obligations, the fence must satisfy the other party’s obligations. This could push up cost.

Examples may mislead: The examples give two clear cases: one party with a pool, the other without; or one party with an exemption, the other without. But many other scenarios exist: both parties have pools with different barrier requirements; one party has a pool but the fence is not the required barrier; a party has a pool but it is not regulated (e.g., depth less than 300 mm). The regulation does not address these, and ACAT will have to fill gaps.

No guidance on what “reasonable” means: Subparagraphs (iii) and (iv) use “reasonable” for requiring contribution or adjusting the amount. The regulation provides no guidance. This invites subjective decisions and possible inconsistency. A party may think it unreasonable to pay for a pool safety fence when they have no pool and no children; another party may think it entirely reasonable because the fence benefits both by making the pool safer for visitors. The regulation leaves this open.

Reliance on Building Act definitions that may change: The regulation uses definitions from the Building Act. If the Building Act is amended to expand or contract the definition of regulated swimming pool, the regulation’s scope changes automatically. A pool that is regulated today may not be regulated tomorrow, or vice versa, possibly after a fence has been erected and costs allocated. This could create retrospective issues.

No presumption of adjustment: The regulation merely says ACAT must take the matters into account. It does not create any presumption that costs should be adjusted or that the pool-owning party should pay more. A tribunal could consider the factors and decide to stick with equal sharing. Parties should not assume they will get a cost adjustment.

Counsel will need Building Act evidence: To satisfy the regulation, a party will likely need to lead evidence about the Building Act compliance status of each party, including whether any exemptions apply. This may involve obtaining certificates from the ACT Planning and Land Authority or expert evidence about the fence’s compliance. This adds expense and delay to what could have been a minor dispute.

Application to existing fences: The regulation applies to determinations about repair or replacement of existing fences (sections 11 and 12 of the Act) as well as new fences. So if an existing fence is also a safety barrier, and a neighbour wants to replace it, the regulation applies even if the fence was built before the regulation commenced. The regulation is procedural, so it applies to all proceedings commenced after its commencement, regardless of when the fence was built.

For parties in a fencing dispute: If you own a regulated swimming pool adjoining a boundary fence, and you need to erect, repair, or replace that fence, you should be aware that the regulation may allow you to argue that your neighbour should contribute a higher proportion of the cost, because the fence must also be a compliant safety barrier. Conversely, if you are the neighbour without a pool, you may argue that the cost should be adjusted to reflect your lower compliance burden. In either case, you should gather evidence of: (a) whether each party must comply with Building Act pool safety requirements (e.g., have a regulated pool, or an exemption); (b) the cost of a fence that meets all those requirements (the compliant fence) versus a fence that does not (the non-compliant fence, which might be a standard fence of similar materials); (c) the difference in cost, if any. This means obtaining at least two quotes from fencing contractors - one for a compliant fence and one for a non-compliant fence. You should also gather any documents showing the pool’s regulation status (e.g., pool safety compliance certificates, exemption letters).

For a party applying to ACAT: In your application, you should explicitly refer to the regulation and state whether you believe there is a disparity in compliance obligations. You should be prepared to lead evidence on the matters in section 3(1). If you are the party with the greater compliance burden, you might argue for adjustment. If you are the other party, you might argue that no adjustment is warranted. You should also consider whether the fence truly is a safety barrier for the regulated swimming pool - if the pool has a separate safety barrier and the dividing fence is not part of it, the regulation may not apply.

For ACAT members: When hearing a fencing dispute, you must first determine whether the fence in question is a safety barrier for a regulated swimming pool as defined in the Building Act. You must then consider whether each party must comply with pool safety requirements and whether any exemptions apply. You should then compare the cost of a compliant fence (meeting all parties’ requirements) with the cost of a fence that is not compliant (perhaps a standard fence). If the compliant fence costs more, you must consider the specific adjustment questions under section 3(1)(c) for the determination type before you. You should give reasons showing you have taken these matters into account to avoid appeal.

For legal practitioners: When a client consults you about a fencing dispute involving a pool, start by checking the Building Act definitions to confirm the pool is regulated and the fence is a safety barrier. Obtain evidence of exemptions. Advise your client on the likely costs of litigation given the need for expert evidence on fence costs. Consider settlement possibilities: the regulation may encourage negotiation where parties share the cost differential in a mutually agreeable way, avoiding ACAT proceedings entirely.

For conveyancers and property professionals: When acting for a buyer of property adjoining a pool, advise them of the potential liability to contribute extra fencing costs. For a seller, disclose any pending fencing disputes. The regulation may affect property value if the neighbour is likely to demand contribution for a new compliant fence. There is no statutory duty to disclose such matters, but prudent practice may suggest doing so.

For fencing contractors: When asked to quote for a boundary fence that adjoins a pool, clarify with the client whether the fence must be a compliant safety barrier. Quote separately for compliant and non-compliant options. Note that the regulation may affect who pays, but that does not affect your contractual relationship with your client. You may be asked to provide written evidence of the cost difference, so document your quotes clearly.

General strategy: Because the regulation is new and untested, parties should consider alternative dispute resolution before ACAT proceedings. A mediated agreement that allocates the additional cost of a compliant fence in some agreed proportion (e.g., 50-50, or 70-30) may save legal fees and avoid the risk of an unpredictable ACAT decision. The regulation gives a framework for negotiation, but it does not dictate the outcome.