Bathroom Renovation Plumbing.Done Right.

Two visits

Plumbers work in two stages on a bathroom. Rough-in is first, when pipes and drains are placed. Fit-off is last, when taps, toilets, showers and basins are installed.

Getting rough-in right

Mistakes at rough-in are hard to fix once the tiles are down. We check positions against your fixtures and the plans before closing up.

Waste and falls

Drains need the right fall and the right position. We set up floor wastes and shower drains so water leaves the room.

Where plumbing fits in a bathroom renovation

Plumbing runs through a bathroom job twice. First comes the rough in, when the old fixtures come out and new pipes, drains and wall frames are set before the walls are lined and waterproofed. Then comes the fit off, when the tiles are done and we connect the toilet, basin, shower, taps and any heated rail or bidet. Both visits matter. If the rough in is wrong, the only fix is cutting into new tiles.

Decisions to make before the work starts

Where does the shower go and what sort of floor waste do you want? Do you want a wall hung toilet with an in-wall cistern, which needs a frame and access? Will the vanity sit on the same wall as the old one? Will you keep the existing hot water system or does a bigger bathroom need more capacity? Taps, basins and toilets have different pipe positions, so pick fixtures early and give us the model details.

Checking what is behind the old walls

When walls open, we look at the condition of the existing pipes. Old galvanised pipes with rust inside, brittle plastic fittings and drains with the wrong fall are cheap to replace now and expensive to replace later. You should be told what is found and given the choice.

Working with your builder and waterproofer

Waterproofing in wet areas is a separate licensed trade. We set pipe and drain positions so the waterproofer can do a clean job, and we return after the tiling to finish. We are happy to work to your builder's timeline or run the job for you.

Paperwork and finish

Some of this work needs a compliance certificate. The licensed plumber lodges it and you should receive a copy. Every outlet should be tested for leaks and flow before the job is finished. Ask where the isolation valves are.

What changes the price and the schedule

Moving the toilet, shower or floor waste costs more than swapping fixtures in the same spots, because walls or slabs may need to be opened. Wall hung toilets need a frame. Old galvanised pipes found behind the wall can add work. Plumbing has two stages, rough in before the walls are lined and fit off after tiling, so the order of trades matters. Ask for both stages to be listed in the quote.

How a bathroom plumbing job usually runs

Strip out comes first. Old fixtures, wall and floor linings and sometimes the old waste pipes come out. The plumber then does the rough in: water supply to the shower, basin and toilet position, the toilet and basin waste, and the shower floor waste, set to the right falls so water runs to the drain. Then the waterproofer, tiler and builder do their part. Fit off comes last: taps, shower rail or mixer, toilet, basin and any heated rail or bidet are connected and tested.

The order matters because a mistake behind tiles is expensive. A wrong waste position can mean cutting new tiles. Agree the fixtures and the layout drawing before rough in starts, and ask for a pressure test of the new pipework before the walls close.

Mistakes that cost homeowners money

Buying fixtures after rough in, so the positions do not match. Moving the toilet without checking the floor and the drain. Letting the tiler start before the plumber has signed off the rough in. Leaving out an isolation valve for the shower so the next repair means shutting off the house. Forgetting to plan the heated towel rail power, which is an electrician job.

Ask who coordinates the trades. If you are your own project manager, write the order down: strip out, rough in, waterproof, tile, fit off. Skipping a step is how leaks start behind a finished wall.

Waterproofing and plumbing together

Waterproofing in a bathroom is done by a licensed waterproofer, and plumbing penetrations such as the waste and shower outlet need to be sealed into the membrane. Leave plumbing positions marked and tell the waterproofer where the outlets are.

Fixtures and compliance

Taps, basins, toilets and showers should suit the water supply and the layout. Keep manuals, warranties and plumbing compliance certificates with your renovation records.

Hot water for a new bathroom

A larger bath, a rain shower or a second bathroom adds demand for hot water. Check whether the existing system can supply the new fixtures, and how far the pipe runs from the system to the bathroom. A long run wastes water while you wait for it to heat.

Drain and floor waste planning

Moving a shower or toilet changes the drain route. Floor waste position affects tiling falls. Plan layout with the plumber before design is final.

Get position changes confirmed in writing.

Fixtures and supply fittings

Check that taps, mixers and showers are suitable for your water pressure and hot water type. Some rain showers need higher pressure.

Provide model numbers to the plumber before ordering.

Questions to ask your plumber

Ask when the plumber will be on site, who orders the fixtures, how changes are handled, what is tested and what paperwork you get. Ask how the plumber works with the waterproofer and tiler.

Get quotes in writing, with inclusions and exclusions. A clear quote helps you compare.

Guides worth reading

• Renovation Plumbing: What to Plan Before You Start

Related plumbing services

• Kitchen and Laundry Plumbing: Plumbing for new and renovated kitchens and laundries.
• Renovation Plumbing: Plumbing for renovations, extensions and layout changes.
• New Home Plumbing: Plumbing for new homes from slab stage to final fit-off.
• Emergency plumbing is available 24 hours a day, 7 days a week

Talk to GSA Plumbing Services

Call 0401 041 103 or send an enquiry on the contact page. We work across Geelong, Melbourne and surrounding suburbs.