For anyone planning a home, extension or small development on or near a former landfill or old tip in Victoria. Last reviewed June 2026.
Yes — building on or near a former landfill is common and is usually manageable, provided the site is properly assessed and any gas protection measures are designed into the building. The main concern is landfill gas migrating through the ground into enclosed or below-ground parts of a new building. In Victoria, your council will typically require a landfill gas risk assessment as part of the planning permit, and where a risk is found, well-established design measures keep the building safe. The rest of this guide explains the real risks, what Victoria requires, and how the problem is solved in practice.
Old tips and closed landfills continue to generate gas as buried organic waste breaks down. Landfill gas is approximately 50% methane (CH₄) and approximately 50% carbon dioxide (CO₂), plus trace gases such as hydrogen sulphide and volatile organic compounds. The two hazards that matter for a building are:
The key word is enclosed. Outdoors, landfill gas disperses harmlessly. The concern is gas finding its way into the sealed, below-ground or poorly ventilated parts of a building — which is exactly why the design of a new build matters so much, and why it can be controlled.
Gas moves away from a landfill under pressure and by diffusion, travelling along pathways in the ground. Permeable materials — sand, gravel and loose fill — let gas move laterally, and service trenches and underground conduits are a very common preferential pathway, effectively piping gas towards a building. By contrast, low-permeability ground such as clay or basalt resists lateral migration. Geology is therefore one of the biggest factors in whether a nearby development is actually at risk.
Time matters too. Gas generation is highest when a landfill is young and falls over decades; a roughly 30-year aftercare period is a common benchmark, and by 50-plus years generation is usually low. That said, many old tips are poorly documented, so age alone is never decisive — it is one input into the assessment, not a free pass.
Risk also depends on what you are building. Below-ground and sensitive uses raise the concern most — homes with basements, childcare and aged care. A single-storey home on a well-ventilated slab is lower concern than a development with a basement car park; open space lower still.
If you propose development on or near a current or former landfill — particularly residential or other sensitive uses — your council, as the planning authority, will typically require a landfill gas risk assessment as part of your planning permit. The driver is the planning permit process combined with EPA Victoria's guidance, not a single fixed distance.
The current framework is EPA Victoria's landfill buffer guideline (2024) — Publication 1950, with the related separation distance guideline (Publication 1949), both finalised in August 2024. These superseded the older Publication 1642. The approach is staged and risk-based: depending on the landfill (waste type, size, age) and the development proposed, the outcome is one of three — (a) no further assessment, (b) a landfill gas risk assessment, or (c) an environmental audit (currently a Part 8.3 environmental audit under the Environment Protection Act 2017; the legacy term some people still use is a "section 53V audit").
One point of confusion worth clearing up: you may read that landfills carry buffers of up to 1,500 metres. That figure is about siting a brand-new landfill away from homes — it is not the distance that triggers an assessment when you develop near an existing one. For developing near a former landfill, historically around 500 metres has been the distance within which gas risk is typically considered. Treat that as a guide only: your council and the EPA guideline, applied to your specific site, determine what is actually needed.
A landfill gas risk assessment asks a single practical question: can gas migrate from the source, along a pathway, to a receptor (you and your building)? It uses the Source–Pathway–Receptor model and the CIRIA C665 risk framework. Typical stages are:
The result is a report with clear conclusions and, where needed, recommended gas protection measures designed for your building. Many sites resolve at the desktop stage; only some need monitoring.
This is the reassuring part: where a risk is identified, building near a former landfill is a well-understood engineering problem with standard, proven solutions. Measures are layered so that no single component carries the whole job, and are matched to the assessed risk level. Common measures include:
For most homes and small developments the protective measures are modest and built in during construction, where they are far cheaper and simpler than retrofitting later. The earlier you know what your site needs, the easier it is to design around.
If your council has asked for a landfill gas assessment, or you simply want to know where your site stands before you design, Automated Environmental can scope it for your site — request a free LFG RA quote or read more about our landfill gas risk assessments.
In most cases, yes — provided the site is properly assessed and any required gas protection measures are designed into the building. The risk is landfill gas migrating into enclosed or below-ground spaces, and it is controlled with proven measures such as gas-resistant membranes and ventilated subfloors. A landfill gas risk assessment establishes whether your specific site needs them.
Building directly on a former landfill is more complex than building nearby, but it is done regularly with the right engineering. It requires a thorough assessment of gas, settlement and contamination, and typically a more robust set of gas protection and ground-improvement measures. In Victoria it may also trigger an environmental audit. It is manageable, but get it assessed early so the design and budget reflect what the site actually needs.
Often, yes. If you propose development on or near a current or former landfill — especially homes or other sensitive uses — your council will commonly require a landfill gas risk assessment as part of the planning permit, guided by EPA Victoria's landfill buffer guideline. Whether your specific site needs one depends on the landfill, your proposal and the guideline applied to your site, so it is best confirmed early.
The common measures are gas-resistant membranes beneath the slab, ventilated subfloors or a passive venting layer that lets gas escape safely, careful sealing of service entries where pipes and cables enter the building, particular attention to enclosed spaces such as basements, and verification or monitoring on higher-risk sites. They are layered and matched to the assessed risk, and are far easier to build in during construction than to retrofit.
Start with Victoria Unearthed, the free Victorian Government online map that searches a property for potentially contaminated land and current or former landfills. Be aware that many old or closed tips are poorly documented or unregistered, so a clear map result is not a guarantee. A professional desktop review goes further, checking historical aerial photographs and other records to confirm what was once on or near your site.
Related reading: Is it safe to live near a landfill? · How to check if your property is near a former landfill · Do I need a landfill gas risk assessment for a planning permit?
This article is general information, not legal or professional advice. EPA Victoria guidance should be read in full and professional advice obtained for your specific site and circumstances.