Plumbing & Drains — Who's Responsible?

There's a practical rule for plumbing in NSW strata: a pipe that serves only your lot and sits inside your lot is usually yours. Shared pipes, and pipes inside the wall or floor structure, are common property. It solves most plumbing disputes once you know which pipe you're looking at.

What we're talking about

Plumbing in a townhouse scheme generally covers:

• Water supply from the meter to and through each townhouse
• Hot and cold pipes inside the lot
• Toilets, basins, baths, showers, sinks (the fixtures themselves)
• Waste pipes from each fixture
• Waste stacks that run between floors
• The sewer line that takes wastewater out to the council main
• Stormwater drains and downpipes

The rule — where the pipe sits and what it serves

Common property is any part of the scheme that isn't inside a lot (Strata Schemes Development Act 2015, s4), and unless your plan says otherwise your lot ends at the inner surface of the walls, the upper surface of the floor and the under surface of the ceiling (s6). For pipes, that means:

• If the pipe is inside the wall, floor or ceiling structure — it's outside your lot, so it's common property.
• Shared stacks, mains and pipes serving more than one lot — common property.
• If the pipe serves only your lot and sits inside your lot's space (not in the wall or floor) — it's yours.

This sounds simple. In practice, working out which pipe is which takes a plumber, a torch, and sometimes a borescope.

Typical position

Grey areas and common disputes

Blocked drains

The classic "who pays the plumber" question. The honest test:

• If the blockage is in a fitting or pipe inside your lot that serves only your lot, it's your problem.
• If it's in a shared line, or a pipe inside the wall or floor structure, it's the OC's problem — and if one owner caused it, the OC can recover the cost from them (s132 or s120).
• If you don't know where it is when the plumber turns up, get them to identify and document the location before they start work. Whoever pays the bill is the person whose pipe was blocked.

A good emergency rule: if more than one lot is affected, it's almost certainly common property. If only your toilet is backed up, it's almost certainly yours.

Flexible hoses

The plumbing industry's least favourite product. Flexible hoses under sinks burst with worrying frequency, often when no one's home. The hose itself is lot property. Damage to the lot is the owner's problem (and the owner's insurance). Damage to common property may also fall back on the owner — particularly if the hose was clearly old, worn or never replaced. Replace them every 5-10 years. Check them every 12 months.

Hot water systems

Hot water systems are usually lot property in townhouse schemes — each townhouse has its own. See Hot water systems for the full picture.

Sewer roots and old earthenware pipes

Many older townhouse schemes have terracotta or earthenware sewer mains, sometimes 50+ years old. Tree roots get in through the joints. CCTV inspection of the main sewer is one of the best capital works investments a small scheme can make, particularly if blockages are recurring. Once you know what's in the line, you can budget properly.

Insurance and water damage

If a burst pipe damages your lot or your neighbour's, two separate questions need answering:

• Who's responsible for the pipe itself? (Lot or OC, per the rules above.)
• Whose insurance pays for the resulting damage?

The OC's strata insurance covers the building structure and common property. Your contents and your fixtures inside the lot are covered by your contents insurance (or landlord insurance if you rent it out). Talk to both insurers as soon as a claim is on the cards.