Renovating a Sydney apartment involves a layer that house renovations do not: you do not own most of the building you are altering. The walls, floors, ceilings, windows and services that define your apartment are, in large part, common property belonging to the owners corporation. What you own is essentially the airspace within, and the fixtures inside it.
This does not prevent renovation. Sydney apartments are renovated constantly and well. It does mean the process runs through the owners corporation before it runs through a builder, and that projects which ignore this sequence get stopped mid-demolition by a strata manager’s letter.
Understanding What You Own
Under NSW strata legislation, the boundary between lot property and common property is generally the inner surface of the structural walls, floors and ceilings — though the registered strata plan is the authority and can vary this.
Typically:
- Lot property — internal non-structural walls, floor coverings, wall linings and paint, kitchen and bathroom fixtures and fittings, internal doors, light fittings, and the pipes and wiring that serve only your lot
- Common property — structural walls and slabs, the building envelope, windows and external doors, balconies (usually), the waterproofing membrane, the plumbing stacks, the main electrical infrastructure, and anything serving more than one lot
The consequence: replacing a kitchen is largely your business, while removing a wall, altering a window, changing a balcony surface, or touching the waterproofing membrane is not.
The Three Categories of Strata Renovation
NSW strata law divides renovation work into three tiers, each with a different approval requirement.
Cosmetic work — no approval needed
Work you can carry out without permission, provided you take responsibility for any damage. This includes:
- Painting internal walls
- Filling minor holes and cracks
- Laying carpet
- Installing or replacing built-in wardrobes
- Installing or replacing internal blinds and curtains
- Hanging pictures, shelves, handrails and similar fixtures
You must still repair any damage to common property caused by the work.
Minor renovations — approval by ordinary resolution
Work requiring approval by a majority vote of the owners corporation, or of the strata committee where the by-laws delegate that power. This category commonly includes:
- Renovating a kitchen
- Changing recessed light fittings
- Installing or replacing wood or hard floors
- Removing carpet to expose underlying floorboards
- Installing a reverse-cycle split system air conditioner
- Removing non-structural internal walls
- Installing rails, wiring, cabling or recessed light fittings
Approval cannot be unreasonably refused. Applications must include details of the work, the contractors, timeframes, and arrangements for cleaning and rubbish removal.
Major renovations — special resolution and a by-law
Work affecting common property or the building’s external appearance requires a special resolution at a general meeting — 75 per cent of votes cast — and usually a registered common property rights by-law. This includes:
- Any bathroom or laundry renovation, because it disturbs the waterproofing membrane, which is common property
- Removing or altering structural walls
- Altering windows, external doors or balcony enclosures
- Changing balcony tiling or waterproofing
- Relocating plumbing that connects to the common stacks
- Installing external air conditioning condensers
- Anything altering the external appearance of the building
The by-law is the key document. It records what you are permitted to do, and — critically — allocates ongoing responsibility for maintaining and repairing the altered common property to you and to every future owner of your lot. Preparing and registering a by-law costs $1,200 to $3,500 in legal and registration fees.
The Approval Process in Practice
A realistic sequence for a Sydney apartment renovation:
- Obtain the strata plan and the by-laws. Order a strata search or request them from the strata manager. Read the renovation by-laws specifically — many Sydney buildings have detailed ones covering work hours, lift protection, floor covering acoustic ratings and contractor insurance.
- Speak to the strata manager early to establish which category your work falls into and what the building requires.
- Prepare the application. Scope of work, drawings, contractor details, licences, insurance certificates, a work program, and arrangements for waste and access.
- Have a by-law drafted by a strata lawyer where major works are involved.
- Get it on a meeting agenda. This is where timing bites. A general meeting requires notice, and if the AGM has just passed, an extraordinary general meeting must be convened — which the owners corporation may charge you for.
- Obtain the resolution and register the by-law with NSW Land Registry Services.
- Then consider council approval, which is a separate question.
Allow three to six months from first enquiry to approval for major works. Buildings with engaged committees and clear by-laws move faster; buildings in dispute can take a year.
Council Approval Is Separate
Strata approval is not planning approval, and vice versa. Most internal apartment renovations in NSW are exempt development requiring no council approval, provided they do not affect structure, fire separation or external appearance. However, you will need council or certifier involvement where you:
- Alter or remove a structural wall
- Change the external appearance of the building
- Alter fire-rated construction or fire safety measures
- Enclose a balcony
Fire safety is the item most often overlooked. Apartment buildings have fire-rated separations between lots and to common corridors, and penetrating them — for a rangehood duct, a recessed light, or a relocated service — compromises a system the building’s annual fire safety statement depends on. Our guide to council approval in Sydney covers the pathways.
The Practical Constraints of Apartment Work
Concrete slabs
Most Sydney apartments sit on post-tensioned or conventionally reinforced concrete slabs. This has three consequences:
- Plumbing cannot easily move. Waste pipes are cast into or run beneath the slab. Relocating a toilet, shower or kitchen sink may require core drilling, which in a post-tensioned slab is dangerous without a scan to locate tendons, and may be prohibited outright. Where it is permitted, expect $4,000 to $8,000 and an engineer’s involvement.
- Floor levels are fixed. There is often no set-down available for a hobless shower, forcing either a raised floor across the bathroom or a step.
- Chasing walls for electrical is limited where walls are concrete rather than framed.
Acoustic requirements
Most Sydney strata by-laws impose a minimum acoustic rating for hard floor coverings — commonly requiring a specified impact insulation performance. Replacing carpet with timber or tile without the required acoustic underlay is one of the most common sources of strata disputes, and the remedy is removal of the floor.
For more detail on this part of the project, see Acoustic Underlay for Apartment Flooring: What to Check Before Buying.
Access and logistics
- Lift bookings and lift protection, often with a bond of $500 to $2,000
- Restricted work hours, typically weekdays only, commonly 8am to 4pm
- No access to common areas for material storage
- Waste removal via the lift and out through the building, adding significant labour
- Loading dock restrictions and street parking permits in inner Sydney
These constraints commonly add 15 to 25 per cent to the labour component of an apartment renovation compared with the same work in a house.
Ventilation
Apartment bathrooms and kitchens usually vent into a shared shaft with a mechanical system serving multiple lots. You generally cannot install your own external discharge, and you must not disturb the shared system. Rangehood selection is often limited to recirculating units.
What an Apartment Renovation Costs in Sydney
- Cosmetic refresh — paint, floor coverings, light fittings, tapware: $12,000 to $30,000
- Kitchen renovation — $20,000 to $50,000
- Bathroom renovation — $25,000 to $45,000, higher than an equivalent house bathroom because of access, waste handling and slab constraints
- Full two-bedroom apartment renovation — $80,000 to $180,000
- High-end apartment renovation — $200,000 to $600,000
Add the strata costs: by-law preparation and registration at $1,200 to $3,500, potential EGM convening costs, lift and building bonds, and in some buildings a levy toward the owners corporation’s legal review of your application.
Waterproofing Is the Critical Risk
In a house, a failed bathroom membrane damages your own property. In an apartment, it damages the lot below, and you will be pursued for it by the affected owner, the owners corporation, and potentially both insurers.
Because the membrane is common property, altering it without a registered by-law can also leave you personally liable for consequential damage without the protection of the owners corporation’s insurance.
The non-negotiables for a Sydney apartment bathroom:
- A licensed waterproofer and a certificate of compliance
- Comprehensive photographs of the completed membrane before tiling
- A flood test before tiling, without exception
- A registered by-law covering the alteration and allocating maintenance responsibility
- Contractor public liability insurance naming the owners corporation, which most by-laws require
See our detailed guide to waterproofing and wet area compliance in Sydney.
Making It Go Smoothly
- Read the by-laws before you buy, if the apartment is a renovation project. Some Sydney buildings have restrictive by-laws that make meaningful renovation impractical.
- Talk to the committee, not just the strata manager. The committee votes. A neighbour who understands your plans and your timeline is far less likely to object.
- Present a professional application. Drawings, licences, insurance, a program and a waste plan. Committees approve applications that look managed and defer ones that look improvised.
- Commit to the constraints in writing — work hours, lift protection, corridor cleaning, and a completion date.
- Use a builder who works in strata regularly. The logistics are a specialised skill and a builder unfamiliar with them will underquote and then struggle.
- Notify neighbours directly before work starts. Most apartment renovation complaints are about surprise, not noise.
Apartment renovation in Sydney is slower and more procedural than house renovation, but the constraints are knowable in advance. The projects that go badly are almost never stopped by the strata scheme itself — they are stopped by an owner who started demolition before finding out what the strata plan said they owned.
Flooring: The Most Common Strata Dispute
Replacing carpet with a hard floor is the single most frequent source of conflict in Sydney apartment buildings, because impact noise transmits through concrete slabs far more readily than most owners expect.
Almost every Sydney strata scheme with by-laws written in the last two decades imposes an acoustic performance requirement on hard floor coverings. The requirement is expressed as a measured impact insulation performance, and it applies to the finished floor system — the covering plus its underlay — not to the underlay alone.
Practical requirements:
- Obtain the by-law’s specific acoustic requirement before selecting any product
- Use an acoustic underlay tested as a system with your chosen floor covering, and obtain the test certificate
- Include perimeter isolation so the floor does not bridge to the walls, which short-circuits the acoustic separation
- Retain the certificate and the installer’s declaration for the owners corporation
- Consider a post-installation acoustic test where the by-law requires one, at $800 to $2,000
The consequence of getting this wrong is severe: the owners corporation can require the floor to be removed and replaced at your cost, and neighbours can pursue the matter through NCAT. This is not a theoretical risk; it happens regularly across Sydney.
Balconies and External Areas
Balconies are almost always common property, even where the by-laws grant the lot owner exclusive use. That means the slab, the balustrade, the waterproofing membrane and the drainage all belong to the owners corporation.
What this means in practice:
- Re-tiling a balcony disturbs common property waterproofing and requires a special resolution and a by-law
- Balustrade changes alter the building’s external appearance and require approval, plus compliance with current safety standards
- Pedestal-mounted decking tiles laid over the existing surface are often a practical alternative, as they are removable and do not disturb the membrane — but check the by-laws, as some schemes prohibit any added load or covering
- Enclosing or glazing a balcony is a major alteration requiring both strata approval and council approval, and frequently affects the building’s fire engineering
- Planters and heavy pots can exceed the balcony’s design load and trap moisture against the membrane
Air Conditioning
Installing a split system in a Sydney apartment involves the external condenser unit, which sits on common property and is visible from outside the building. This is a major alteration in most schemes.
A related guide to consider while planning this work is Kitchen Renovation Costs in Sydney: What You Actually Pay in 2026.
The considerations the owners corporation will weigh: the location and visibility of the condenser, noise to neighbouring lots, condensate drainage, the penetration through the building envelope, and whether the building has a designated location or a nominated system type. Many Sydney buildings have adopted a standard approach — a specified brand, a designated condenser location, and a pre-approved installation detail — precisely to avoid dealing with each application individually. Ask before designing anything.