Having a functional shower drain is crucial to avoiding floods and the potential health risks from mould and stagnant water. If you’ve recently bought a new property, the existing shower drain might need to be replaced.
The process isn’t overly complicated, but it’s wise to know a few details before starting. With these tips, the installation or replacement should take only a few hours.
This guide will cover all the essential points for your shower plumbing project. If it still seems daunting, don’t hesitate to call for professional help.
Let’s dive in!
Things To Know Before Installing A Shower Drain
1. Eliminate Any Pipe Size Issues
One key point to remember is that pipe sizes must meet national trade standards. Under AS/NZS 3500.2, standard shower waste outlets in Australian homes are DN50 (50mm), while high-capacity linear drains or double-shower configurations often require DN65 or DN80 pipework to prevent water backing up over the hob or frameless screen.
Whether installing a classic point drain, a tile-insert smart waste, or a sleek linear trench grate, ensuring your drain diameter matches showerhead flow rate is essential to stop pooling. A licensed plumber will ensure the waste and trap sizing comply with Sydney drainage requirements.
2. Working With Tight Spots
You might have difficulty using thick pliers in tight spots that might not have enough space to fit well. When working with a properly installed shower drain, the person might have to cut through the ceiling below the shower floor. There could be a lot of pipes and wires, making it difficult to use the water pliers on the nut that attaches to the pipes and drain flange.
So, if you cannot remove the nut or reach the drainpipe, you might have to pull up the entire shower base to get to the drain body. That would require a lot of plumbing work, making it time-consuming.
However, there is a way to prevent this from happening. You can permanently attach a lock nut-style drain, which can be put in place by jacking screws from the bottom with the help of a screwdriver; you will not need water pliers. The screwdriver will quickly enter tight spots and tighten the screws from underneath, securing the rubber sealing washer and rubber gasket effectively when you install a shower drain.
3. Cut Through The Ceiling
You might need to cut through the ceiling beneath the shower. If there’s any leakage, it might be necessary to remove and replace both the drain and the plasterboard underneath.
Replacing plasterboard is relatively straightforward when cutting an access hatch through the ceiling below. This can be covered with an air grill that can be removed to access the plumbing.
You will not have to dig a hole in the ceiling if the shower base and the drain are replaced. Instead, remove the existing shower pan and then the installed drain. Next, attach the new shower pan with the latest drain before setting it.
We feel that “friction” or “compression” drains work the best for this job. They have a gasket inside the body of the drain, which should be removed and coated with a plumber’s soap. And after the shower base is put in place, you can slide the gasket back. The compression nut will need to be tightened to seal it, and you can do that with the help of a screwdriver.
4. Replacing The Trap
When installing a new shower drain, the old drain pipe must be cut to remove the old drain. This usually shortens the drain pipe a little, which needs to be extended later to install the new drain.
Sometimes, this process of extending may become difficult as well as time-consuming. Hence, many just cut the drain trap and replace it to simplify the process. Keep this in mind before you start working with the new shower drain.
5. Keep Weep Holes Open
If you have a tiled bathroom floor, replacing the shower drain could mean changing the entire flooring. After all, tiles are placed on a mortar bed on top of a waterproof membrane placed on another. In other words, the shower drain is cemented, making drain installation challenging.
Tiled floors pose another problem involving grouts, which can crack, causing water to leak. Holes must be in the middle to allow the water to pass through.
Under Australian Standard AS 3740 (the national code governing the waterproofing of domestic wet areas to protect structural timber and subfloors from catastrophic water damage) and AS/NZS 3500.2, shower waste connections must integrate a certified puddle flange with clear weep holes. This allows any subsurface moisture penetrating tile grout to drain directly into the waste pipe rather than pooling on the membrane. Ensuring weep holes remain free of screed and mortar is vital for long-term waterproofing integrity.
Replacing Your Shower Drain
As shower drains age, replacing them becomes trickier. Metallic or stainless steel pipes can corrode, complicating removal. Plus, differences between old and new models can mean extra work. You might need to swap out rusted parts, like the top flange or drain assembly.
The tips above highlight the careful planning needed to replace shower drainage without compromising waterproofing membranes. Operating under NSW Fair Trading Contractor Licence 305428C, Fixed Today is the established plumbing service Sydney households have trusted and relied on since 2011 across more than 15 years.
When you contact us about a shower drain project, our team asks a couple of practical diagnostic questions about your bathroom structure (such as concrete slab vs timber subfloor and existing tile membranes) before dispatch so our technicians arrive equipped with compliant puddle flanges, linear drain fittings, and diagnostic cameras. We explain every installation step clearly on site, backed by honest pricing and a $0 call-out fee on approved work. Speak with our Sydney shower drainage team today.
