Natural Gas vs LPG for Residential Builds in Australia

What it is

Natural gas and LPG are the two main gaseous fuels supplied to Australian dwellings. Natural gas is mostly methane delivered through a reticulated street network at low pressure. LPG is propane or a propane-butane blend stored in cylinders or bulk tanks on the property. Both fuels run through AS/NZS 5601.1 for installation rules and rely on AS/NZS 5263 for appliance compliance.

For a builder, the choice between the two affects the meter or tank location, the appliance selection and the building approval pathway. In Victoria the choice is also constrained by the gas connection ban on most new residential planning permit applications lodged from 1 January 2024.

Natural gas supply

Natural gas connects from the street main through a service line to a regulator and meter at the property boundary or building wall. The distributor owns the assets up to and including the meter. Beyond the meter the consumer piping falls under AS/NZS 5601.1 and the gasfitter who installs it.

Reticulated natural gas is available in most metropolitan areas of NSW, Victoria, South Australia, Queensland and parts of Western Australia. The Victorian network is the densest. Connection charges and lead times vary by distributor. APA, Jemena, AusNet and ATCO all run the major distribution networks.

LPG supply

LPG arrives in either 45 kg exchange cylinders or a bulk tank from 0.5 to 7.5 kilolitres. Twin 45 kg cylinder installations are the standard for residential use, with an automatic changeover valve so supply continues when one cylinder empties. Bulk tanks suit rural homes with high gas demand or limited cylinder access.

The cylinder or tank is supplier owned but the slab, location, signage and pipework are the builder responsibility. AS/NZS 1596 sets the storage and handling rules for LP gas. Setback distances apply from ignition sources, windows, drains and property boundaries.

AS/NZS 5601.1

AS/NZS 5601.1 General installations covers pipework, appliances, flues, air ducts and ventilation for any gas installation. The 2022 edition is the current adopted version in most states. AS/NZS 5601.2 covers caravans and boats.

The standard sets sizing tables for pipework, isolation valve placement, appliance clearances and ventilation openings. A gasfitter must hold the appropriate licence in the state of work and a Type A appliance must hold AS/NZS 5263 approval. The compliance plate carries the certification mark and the model number.

Regulator placement

Regulator placement follows AS/NZS 5601.1 Section L. The 2022 edition raises the regulator height above ground level to 1500 millimetres in most cases and sets exclusion zones around vents. The exclusion zone is centred on the regulator vent or on the service riser depending on the regulator type.

The exclusion zone keeps ignition sources, electrical fittings, opening windows and air intakes clear of vented gas. The builder needs to coordinate the regulator location with the air conditioning condenser, hot water heat pump and any electrical sub-board. Late changes drive expensive rework.

Ventilation

A gas appliance consumes air for combustion. AS/NZS 5601.1 requires either fixed ventilation openings or proven natural ventilation in the room containing the appliance. Continuous flow water heaters and ducted gas heaters typically sit outside the building envelope so the rule applies mainly to indoor cooktops, indoor space heaters and storage water heaters located inside.

Open flued gas appliances inside negative pressure environments are a special case. Range hoods, bathroom exhaust fans and clothes dryers can create enough negative pressure to draw flue gases back into the room. The Victorian Building Authority and Energy Safe Victoria publish testing requirements for these situations.

Victorian new build restrictions

From 1 January 2024 a planning permit for a new Class 1 dwelling in Victoria can no longer include a natural gas connection in most cases. The change sits in Planning Practice Note 90 and amendments to the Victorian Planning Provisions. Existing dwellings, alterations and additions are not captured. LPG is also restricted in many cases. Builders in Victoria need to design new homes for full electrification with heat pumps for hot water and space heating, plus induction or electric cooking.

The restrictions do not apply to Class 2 to Class 9 buildings on the same scale and rural areas have specific exemptions. Check the planning scheme amendment text and the local council overlay before locking in a fuel choice on a Victorian build.