Written by JSW Plumbing | Published on June 2025
Yes, you can move a shower drain during a bathroom renovation. It requires cutting into the floor slab or subfloor, repositioning the drainage pipe, and making sure the new location still meets fall and venting requirements. This article covers the process, costs, what can go wrong, and what homeowners across Hornsby, Thornleigh and the Hills District need to consider before starting work.
Understand what moving a shower drain actually involves
Moving a shower drain is not a surface-level job. The drain connects to a waste pipe buried beneath your floor, and shifting it means physically relocating that pipe.
For homes built on a concrete slab, a plumber needs to cut or core into the concrete, reposition the pipe, and then patch the slab afterwards. For homes with a suspended timber subfloor, the process is generally easier since pipes run underneath the floor and can be accessed from below.
Either way, this is licensed plumbing work. In New South Wales, all drainage work must be carried out by a licensed plumber and drainer. Unlicensed drainage work is illegal and will create serious problems when you try to sell your home.
The key things that determine how complex the job is include:
- Whether your home is on a concrete slab or a suspended subfloor
- How far you need to move the drain (even 300mm makes a difference)
- The direction of the existing pipe run and whether it conflicts with other services
- The depth of the slab and access to the underfloor space
- Whether the new drain location can still achieve the required 1-in-60 fall to the sewer
Know the NSW regulations that apply to shower drain relocation
In New South Wales, residential drainage work is regulated under the Plumbing and Drainage Act 2011 and must comply with AS/NZS 3500, the Australian standard for plumbing and drainage systems.
Any drainage work that involves moving or extending a drain requires a plumbing permit in most council areas. For homeowners in Hornsby Shire and The Hills Shire, this means your plumber needs to notify the relevant authority and the work needs to be inspected before the floor is closed up.
JSW Plumbing handles all permit applications and inspections as part of the job. You do not need to chase councils yourself.
Critical compliance points for drain relocation in NSW include:
- The waste pipe must maintain a minimum fall of 1:60 toward the sewer
- The drain must be properly trapped to prevent sewer gases entering the home
- All joints and connections must use approved materials and methods
- The work must be inspected before concrete or floor coverings are reinstated
- A certificate of compliance is issued by the licensed plumber upon completion
Compare the costs of moving a shower drain in the Hills District
Cost depends heavily on your floor type and how far the drain needs to move. Below is a realistic breakdown for homes in the Hornsby, Thornleigh and Hills District area based on typical job conditions in 2025.
| Job Type | Typical Cost Range | Notes |
|---|---|---|
| Move drain on timber subfloor (minor, under 500mm) | $600 to $1,200 | Easier access, no concrete cutting needed |
| Move drain on timber subfloor (major, 500mm or more) | $1,200 to $2,500 | May involve re-routing longer pipe sections |
| Move drain on concrete slab (minor) | $1,500 to $2,800 | Includes concrete cutting and patching |
| Move drain on concrete slab (major) | $2,800 to $5,500+ | Deep slabs or complex reroutes cost more |
| Permit and inspection fees | $150 to $400 | Varies by council and scope of work |
These figures do not include tiling, waterproofing, or any builder work to reinstate the floor finish. Those costs are separate and depend on your bathroom renovation scope.
If your renovation involves a full bathroom gut and retile, combining the drain relocation with the broader project can reduce overall costs. Talk to JSW Plumbing early in the planning stage so the plumbing is coordinated with your builder or tiler.
Explore how slab versus subfloor changes everything
The single biggest factor in a shower drain relocation project is what sits under your bathroom floor. Homes in the Hills District and Hornsby area include a real mix of both construction types, so it is worth knowing which applies to your property before getting quotes.
| Floor Type | Access Method | Complexity | Cost Impact |
|---|---|---|---|
| Concrete slab on ground | Must cut into slab from above | High | Higher cost, longer timeline |
| Suspended timber subfloor | Access from below (subfloor crawl space) | Moderate | Lower cost, faster turnaround |
| Suspended concrete (upper floor) | May need ceiling access from below | High | Higher cost, affects room below |
Many older homes in Thornleigh, Beecroft and Pennant Hills sit on suspended timber subfloors, which makes drain relocation more manageable. Newer homes and those in flat-land estates across Castle Hill or Baulkham Hills are more likely to be slab on ground.
If you are not sure which applies to your home, a plumber can confirm this quickly during a site visit. Getting this detail wrong at the quoting stage leads to budget blowouts mid-renovation.
Identify when moving the drain is worth it versus when to redesign the layout
Not every renovation calls for drain relocation. Sometimes a small shift in your shower design can avoid the need entirely. Other times, moving the drain is the only way to achieve the layout you want.
Moving the drain is generally worth it when:
- You are converting a bath space into a walk-in shower and the drain position does not align
- You are changing from a shower recess to a level-entry or barrier-free shower
- Your current drain is in a corner and you want a centre drain or linear drain for aesthetics
- The existing drain location conflicts with new wall or partition positions
Reconsidering the layout may be smarter when:
- The drain only needs to move a small amount and the tiler can handle it with screed
- Your home is on a concrete slab and the budget is tight
- The pipe fall direction means a new location would be very difficult to drain properly
- Other structural or heritage constraints limit what changes are possible
A good plumber will give you an honest answer on whether the move makes practical sense. JSW Plumbing regularly advises clients on this during pre-renovation consultations, often saving them money by suggesting alternatives they had not considered.
Understand the timeline for a shower drain relocation project
Timeline matters when you are coordinating a bathroom renovation with multiple trades. Plumbing rough-in needs to happen before waterproofing and tiling, so delays in the drain relocation can hold up the whole project.
Here is a typical sequence for a drain relocation in the Hills District:
- Site visit and quote (usually within 2 to 5 business days of contact)
- Permit application lodged with the relevant authority (allow 5 to 10 business days)
- Demo and excavation day (1 day for most jobs on timber subfloor, 1 to 2 days on slab)
- Pipe relocation and rough-in inspection (inspection booked within 1 to 3 days of completion)
- Slab or subfloor reinstatement (concrete cure time of 3 to 7 days if applicable)
- Waterproofing and tiling can begin after reinstatement is complete
Total plumbing time for the drain relocation itself is typically 1 to 3 days of active work. The waiting periods for permits and inspections add time but are unavoidable under NSW law.
Book your plumber early in the renovation planning process. Trying to fit in drain relocation after other trades have already started creates coordination problems and sometimes forces costly rework.
FAQs on moving a shower drain during a renovation
Do I need council approval to move a shower drain in NSW?
Yes, in most cases. Drainage work in NSW requires notification to the relevant plumbing authority, and the work must be inspected before it is covered up. Your licensed plumber handles the permit application as part of the job. Councils in Hornsby Shire and The Hills Shire both follow this process.
How far can you move a shower drain?
Can I move a shower drain myself to save money?
No. Drainage work in New South Wales must be carried out by a licensed plumber and drainer. DIY drainage work is illegal and will invalidate your home insurance. It also creates serious problems with property sales and council inspections. The cost of professional work is much lower than the cost of fixing unlicensed drainage later.
Will moving the drain affect my waterproofing?
Yes. Any time the floor is cut or the drain is moved, the waterproofing membrane needs to be reapplied in the affected area. In most bathroom renovations involving drain relocation, the entire shower floor is stripped back and fully re-waterproofed to AS 3740 standards. This is non-negotiable in a wet area.
How much extra does it cost to move a drain on a concrete slab compared to a timber floor?
Expect to pay roughly $800 to $2,000 more for slab work compared to a timber subfloor job of the same complexity. The difference comes from concrete cutting, disposal of rubble, and the time required to patch and cure the slab before the next trade can start.
Can a linear drain be installed when relocating a shower drain?
Yes, and many renovation clients in the Hills District choose this option. A linear drain sits along one wall and creates a sleek, modern look with large-format tiles. It does require the floor to be graded correctly toward the channel. Your plumber and tiler need to coordinate closely on the fall direction and screed depth to get this right.
Wrap up and next steps
Moving a shower drain is completely achievable during a bathroom renovation, but it is not a small job. The floor type, distance of the move, permit requirements and trade coordination all affect cost and timeline. Getting the right advice early saves you money and delays.
JSW Plumbing works with homeowners across Thornleigh, Hornsby and the Hills District on exactly these kinds of renovation plumbing projects. We handle permits, inspections and all licensed drainage work so your renovation stays on track.
Call JSW Plumbing today or request a quote online to get a clear, honest assessment of your shower drain relocation before your renovation begins.