ACAT Neighbour Disputes: Fence, Tree, and Property Damage Claims

A neighbour who refuses to share the cost of a dividing fence, a tree that dropped a branch on your roof, or a renovation that cracked your retaining wall — these disputes land at ACAT more often than most people expect. The good news: ACAT handles civil claims up to $25,000 without requiring a lawyer. The challenge: neighbour disputes follow slightly different pre-action rules depending on whether the problem is a fence, a tree, or general property damage.

Fence Disputes and the Common Boundaries Act

Boundary fence disputes in the ACT are governed by the Common Boundaries Act 1981, not just the general ACAT civil jurisdiction. This matters because the Act imposes a mandatory pre-action step before you can file at ACAT: you must serve a formal Notice to Discuss Fence on your neighbour.

The notice sets out the dispute, invites your neighbour to discuss it, and asks for a response. For a new fence or a planned repair or replacement, give the notice at least 30 days before applying to ACAT. If you have already urgently repaired or replaced the fence and are seeking a contribution, give the notice 14 days before applying.

ACAT's Fence Disputes List handles these applications separately from the general civil disputes list. Use the separate Fence Dispute Application form and attach the Notice to Discuss Fence. Under DI2026-112, the Common Boundaries Act application fee is $195 for an individual or $392 for a corporation; corporations with turnover under $200,000 in the preceding financial year or registered not-for-profits can apply for the individual rate by lodging a Statement as to Nature and Turnover of a Corporation. The tribunal applies the cost-sharing principles in the Common Boundaries Act, not just general contract or tort law.

Keep records of the fence condition before and after any work. Dated photographs, written quotes from fencing contractors, and a copy of the existing survey plan (available from Access Canberra) strengthen your position significantly.

Tree Damage Claims

If a neighbour's tree caused damage to your property — a fallen branch, root invasion cracking your slab, or leaf litter blocking your drainage — the claim goes through ACAT's general civil disputes jurisdiction as a tort (negligence or nuisance) or, in some cases, trespass.

The key question is whether your neighbour knew or should have known the tree was a hazard. Evidence of prior complaints (emails, letters) about overhanging branches or visible root damage helps establish this. If you warned them in writing and they did nothing, your position is stronger.

Before filing, send a standard letter of demand describing the damage, attaching photos and repair quotes, and requesting reimbursement within 14 days. ACAT expects evidence that you attempted direct resolution before applying to the tribunal.

Filing fees follow the standard civil disputes schedule. A tree-damage claim for $8,000 in repairs falls into the $3,001–$15,000 tier: $195 for an individual. You can also claim pre-judgment interest calculated at the RBA cash rate plus 4% per annum from the date the damage occurred until ACAT makes an order.

General Property Damage Between Neighbours

Renovation noise that cracked a shared wall, water runoff from a raised garden bed, a contractor working next door who scratched your car — these fall under ACAT's general civil disputes jurisdiction as claims for damages (negligence, nuisance, or trespass).

The process is the same as any other ACAT civil dispute:

1. Send a letter of demand with the exact amount claimed and supporting evidence
2. File a Civil Dispute Application if the demand is ignored or rejected
3. ACAT generally serves the application on your neighbour by prepaid post
4. Attend the initial Directions Hearing, where ACAT clarifies the issues, explores settlement, and sets directions
5. Attend any conference ACAT directs, then proceed to a hearing if the dispute is not resolved

Name the right respondent. If the damage was caused by a contractor working on your neighbour's property, you may need to claim against the contractor (the individual trading under a business name or the company under its registered name and ACN), your neighbour, or both. Check the ASIC Business Name Search to confirm the contractor's legal identity.

When ACAT's General Civil Disputes List Is Not the Right Route

Some neighbour disputes fall outside ACAT's civil jurisdiction:

• Noise complaints and antisocial behaviour — compliance or public-safety complaints may be handled by Access Canberra or ACT Policing. A claim for damages based on nuisance can fall within ACAT's general civil disputes jurisdiction.
• Development and planning objections — the ACT Planning and Land Authority handles these through a separate ACAT administrative review pathway
• Claims over $25,000 — generally go to the ACT Magistrates Court. You can abandon the excess on the application form to stay in ACAT, permanently waiving that amount, or all participating parties can agree in writing for ACAT to decide the full claim.
• Residential tenancy disputes (damage deposits, bond claims between landlord and tenant) — these go to ACAT's separate Residential Tenancies Division under the Residential Tenancies Act 1997

Practical Tips for Neighbour Disputes

Neighbour disputes are personal in a way that a debt recovery claim against a business is not — you still have to live next to this person. ACAT convenors are experienced at mediating between neighbours during the preliminary conference, and many fence and tree disputes settle at that stage without a formal hearing.

Before filing, consider whether the Conflict Resolution Service (CRS), a free community mediation service in the ACT, could resolve the issue. CRS mediators can sometimes broker a fence-sharing agreement or damage reimbursement plan without any tribunal involvement. If mediation fails, having a CRS record strengthens your ACAT application by showing genuine effort to resolve the dispute.

The ACAT Civil Dispute Claim Guide walks through the full filing sequence — demand letter, forms, fees, service, evidence preparation, and the hearing — with worksheets tailored to ACT property and neighbour disputes.

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