Renovating a bathroom inside an existing Castle Hill house usually needs no council approval, whether your lot is in The Hills Shire or the Hornsby Shire part of the suburb. Townhouses and apartments are different: work that touches the waterproofing needs approval from the owners corporation.
What are Castle Hill bathrooms like?
Castle Hill grew from orchards and market gardens into suburban streets over several decades, so the housing spans a wide range. Single-storey brick-veneer homes from the 1970s and 80s usually have a main bathroom, a separate toilet and a small ensuite. Two-storey homes from the late 1980s to the 2000s put the main bathroom and ensuite upstairs, above the living areas, which changes what can go wrong.
About a quarter of Castle Hill's homes are townhouses, semis or apartments, according to census data. Many townhouse complexes date from the 1990s and 2000s, with compact bathrooms stacked over each other. Since the metro opened in 2019, more apartments have been built around Castle Hill and Hills Showground stations.
| Home type | What you usually find | Usual scope |
|---|---|---|
| Two-storey brick veneer (late 1980s–2000s) | Main bathroom and ensuite upstairs over living areas | Full rebuild, new membrane, check the floor framing and the ceiling below for old leaks |
| Single-storey family home (1970s–80s) | Main bathroom, separate toilet, small ensuite | Combine the toilet, enlarge the ensuite, keep fixtures near existing drains on the slab |
| Townhouse in a strata or community scheme | Compact bathrooms, shared walls and driveways | Scheme approval and by-law conditions, full membrane replacement |
| Newer apartment near the metro | Bathroom less than ten years old | Upgrade finishes; check defects and warranty first |
A general guide only. Many Castle Hill homes have been renovated before.
Which council: The Hills Shire or Hornsby?
Castle Hill is split between two councils. Most of the suburb is under The Hills Shire Council, but the north-eastern corner, roughly beyond Old Northern Road and Castle Hill Road towards Cherrybrook, is under Hornsby Shire Council. Check your rates notice. For a bathroom renovation inside an existing house, neither council needs a development application, provided the structure and exterior don't change.
If the bathroom is part of an extension or a first-floor addition, the two councils apply different development control plans, so the right one matters. Lots backing onto bushland, such as along Bidjigal Reserve and Darling Mills Creek, may be on the bush fire prone land map, which affects new external walls and windows.
Townhouse owners: check whether your complex is strata or community title, then ask the manager for the renovation by-law before you book trades. In a strata scheme, a bathroom renovation that changes the waterproofing is a major renovation that needs a special resolution of the owners corporation.
What should a Castle Hill bathroom plan allow for?
- Upstairs leaks. In two-storey homes, a failing shower often shows first as a stain or bubbling paint on the ceiling below. Ask the trades to inspect the floor framing and replace damaged sheeting before the new membrane goes down.
- Tiled shower bases from the 1980s and 90s often have no membrane or one that has failed. Regrouting won't fix that; a strip-out will.
- Townhouse logistics. Shared driveways, visitor parking and complex rules on skip bins and working hours all affect the job. Mention them up front.
- Parking near the town centre. Around Castle Towers and the station precincts, street parking can be time-limited, so say where a trade vehicle can park.
- Planning to stay? Many long-term owners ask for a step-free shower and wall sheeting strong enough for a future grab rail. Both are easiest during a rebuild.
What should you tell the crew?
Say whether it's a house, townhouse or apartment, roughly when it was built and which bathroom you're renovating. Mention ceiling stains, leaks, mould or cracked tiles, and whether there's a second bathroom you can use. For townhouses and apartments, tell the trades who manages the scheme and whether you want help with the approval paperwork.
We don't publish suburb prices, because scope drives cost. Our Sydney bathroom renovation cost guide explains what moves the price, our small bathroom guide suits townhouse bathrooms, and the bathroom renovations page covers licences and contracts. See also trades in Castle Hill and the wider Hills District. When you're ready, describe the job to MyTradeCrew and we'll send it to up to three vetted local trades from our crew, who quote you directly.
Common questions
Is Castle Hill in The Hills Shire or Hornsby Shire?
Both. Most of Castle Hill is under The Hills Shire Council, while the north-eastern corner, roughly beyond Old Northern Road and Castle Hill Road towards Cherrybrook, is under Hornsby Shire Council. It rarely matters for a bathroom renovation inside the house, but it does matter for extensions, because each council has its own development control plan. Your rates notice will tell you.
Do I need approval to renovate the bathroom in my Castle Hill townhouse?
Usually, yes, from the scheme rather than the council. In a strata scheme, a bathroom renovation that touches the waterproofing is a major renovation and needs a special resolution of the owners corporation. Community title schemes have their own rules. Ask your manager for the by-laws, and expect to provide the scope and the trades' licence and insurance details.
Why is there a stain on the ceiling under my upstairs bathroom?
The most common causes are a failed shower membrane, a leaking waste pipe or a cracked seal around the bath or shower base. Have a plumber or leak detection specialist find the source before you choose a fix. If the membrane has failed, a full strip-out and new membrane is the reliable repair, and the ceiling below can be patched afterwards.
My apartment near the metro is new and the bathroom leaks. What should I do?
Raise it as a defect first. In NSW, builders are responsible for major defects for six years and other defects for two years from completion, and apartment buildings may also have a building bond. Tell your strata manager in writing, because the membrane is usually common property. Don't renovate over a defect the builder may have to fix.
More on bathroom renovations
Scope checklists, price drivers and quote comparisons are on the main Bathroom renovations in Sydney page. For costs, read Bathroom Renovation Cost Sydney: 2026 Price Guide.