Two projects, one timeline
A knock-down-rebuild looks like one project. It is really two, run back to back, with the demolition as the hinge. The demolition is short. Everything around it is long — and most of the delay lives in the handover between them.
This is the sequence that actually works in Sydney.
Stage 1 — Feasibility (weeks 0–6)
Before choosing a builder or a design:
- Planning certificate for the lot: zoning, heritage items or conservation areas, bushfire, flood and other overlays.
- Survey of the block: levels, boundaries, trees, services, neighbouring structures.
- Tree check against council's controls.
- Asbestos likelihood — if the house is pre-1990, assume it is present.
- Budget that includes demolition, asbestos, disconnections, temporary accommodation and site costs.
A heritage conservation area or a protected tree can change the entire project. Find out now.
Stage 2 — Design and builder selection (months 2–5)
Working drawings, engineering, BASIX and the documents needed for approval. The builder's contract should state its site requirements: exactly what the block must look like when handed over.
Typical requirements:
- House, slab, footings and piers removed.
- Paths, driveway and crossover removed if relocating.
- Retaining walls in the new footprint removed.
- Trees within the building envelope removed (with approval).
- Services capped at the boundary.
- Block level and clear.
Stage 3 — Approval (months 4–8+)
Depending on the site, the new home — and usually the demolition — is approved as complying development by an accredited certifier or through a development application to council. See CDC or DA for a Sydney demolition.
A CDC can move relatively quickly once documents are complete. A DA depends on the council, the proposal and whether neighbours object.
Do not book the demolition against a guessed approval date.
Stage 4 — Demolition contract (as approval nears)
Price the demolition from an inspection, matched line by line to the builder's site requirements. See house demolition cost in Sydney.
Stage 5 — Disconnections (start immediately on approval)
The most underestimated stage:
- Electricity — service removal by Ausgrid or Endeavour Energy, depending on location, usually booked through a Level 2 electrician.
- Gas — disconnection and meter removal.
- Water — meter and supply arrangements.
- Sewer — capping by a licensed plumber.
- Telecommunications — where present.
Lead times vary and none can be forced. Start them the day the approval is issued.
Stage 6 — Move out
Only now. Asbestos removal and disconnection work generally require the house to be vacant.
Stage 7 — Asbestos (1–3 weeks)
Survey where not already done, licensed removal by a separately licensed asbestos removalist, regulatory notification by the removalist where required, and clearance. See asbestos before demolition.
Stage 8 — Pre-demolition (days)
- Dilapidation reports on neighbouring properties, where required or sensible.
- Neighbour notification as the approval requires.
- Site set-up — fencing, erosion and sediment controls, tree protection, any footpath or road permits.
Stage 9 — Demolition (typically 1–2 weeks on site)
Soft strip, structure, slab and footings, sorted disposal. Single-storey houses often take three to seven working days; double brick, two storeys or difficult access take longer.
Stage 10 — Handover to builder
The block, as defined in the builder's site requirements, with waste disposal records and asbestos clearance documentation available.
Where the weeks go
| Stage | Commonly underestimated because |
|---|---|
| Approval | DAs run on council's timetable |
| Disconnections | Separate operators, separate lead times |
| Asbestos | Survey, removal and clearance are sequential |
| Trees | Separate permit or approval conditions |
| Neighbours | Dilapidation reports need access and scheduling |
Common traps
Booking the machine before approval. It cannot legally start.
Moving out before disconnections are booked. Rent while nothing happens.
Scope mismatch. The builder expects the driveway gone; the demolition quote left it in.
Assuming a tree can go. Council says no, and the design has to change.
Ignoring asbestos on a brick house. Eaves and wet areas.
Where this matters most
Knock-down-rebuilds are especially common across the Hills District, Ryde, the Sutherland Shire, St George, Bankstown and Parramatta.
Call 02 5943 7968 or send the job details through.
More from Demolition Guides
- Asbestos before demolition in SydneyAsbestos before a Sydney demolition — where it hides in pre-1990 houses, the survey, licensed removal and clearance sequence, and cost.
- CDC or DA for a Sydney demolitionCDC or DA? How a Sydney demolition's approval pathway is decided, what heritage and trees change, and what to check before you sign.
- House demolition cost in Sydney, line by lineWhat it costs to demolish a house in Sydney in 2026 — the bands, every line in a proper quote, and how to compare quotes fairly.
Questions people ask before they commit
How long does a knock-down-rebuild take in Sydney?
From the start of design to moving into the new house, commonly 12 to 18 months or more. The demolition itself is a few weeks of that. Design, approval and construction take most of the time, and disconnection lead times regularly add weeks that people do not expect.
When do I move out?
Only once the approval is issued and the disconnections and demolition are booked. Moving out too early costs rent; moving out too late holds up disconnections and asbestos removal, which cannot happen while the house is occupied.
Does the builder handle demolition?
Some volume builders include it, some subcontract it with a margin, and some leave it to the owner. If the owner arranges it, the demolition contract needs to match the builder's site requirements exactly — what must be removed and when the block must be ready.
Is a knock-down-rebuild cheaper than buying new?
It can be, because you avoid stamp duty and agent fees on a new purchase and keep a location you like. But demolition, approvals, temporary accommodation and site costs such as retaining walls or trees need to be included in the comparison.
What can hold up the demolition?
Approval not issued, disconnections not completed, asbestos not cleared, tree approvals outstanding, or neighbours' dilapidation reports not done. Each is avoidable with early planning.