Knockdown Rebuild: The Real TimelineFrom demo to handover — from someone actually doing it.
By Alex Snaith·March 5, 2026·14 min read·Updated as the build progresses
Every knockdown rebuild timeline on the internet is written by someone selling you a house. This one is written by someone building one — right now, as an owner-builder, updating it as each stage actually happens.
The build
252 square metres. Two-storey knockdown rebuild. Lakefront block on the Central Coast, NSW. Prefab steel frame. Owner-builder managed — meaning I coordinate every trade, every inspection, every invoice, and every decision myself.
I started planning in mid-2025. As of writing this, I'm into the framing stage. This article will be updated as each phase completes, so what you're reading is a living document — not a retrospective.
Why this matters:Most KDR timelines give you a single number ("12 months") without explaining what goes into it. The reality is that a knockdown rebuild involves 7 distinct phases, each with its own dependencies, risks, and delays. Understanding each one is how you avoid being the person who budgets 9 months and finishes in 18.
The full timeline — expected vs actual
Tap each phase to see every step, what I expected it to take, what it actually took (or is taking), and what I learned. Phases marked "upcoming" will be updated as I get there.
Planning & Approvals
Expected: 2–4 monthsActual: 5 months
Complete
Architect / building designer — plans + working drawings
4–8 weeks→ 6 weeks
Multiple revisions. Don't rush this — changes on paper are free, changes on site cost thousands.
Structural engineer
2–3 weeks→ 3 weeks
Depends on complexity. Two-storey with steel beams takes longer than single-storey slab-on-ground.
Soil / geotechnical report
1–2 weeks→ 1 week
Book early. The result affects your slab design and therefore your engineer's timeline.
BASIX certificate
1 week→ 4 days
Energy assessor turns this around quickly. Needed before CDC/DA application.
CDC or DA application + approval
4–10 weeks→ 8 weeks
CDC is faster than DA but not every build qualifies. My certifier handled the CDC. Council can take 40+ days for DA.
Owner-builder permit
2–4 weeks→ 3 weeks
NSW Fair Trading. Need to complete the OB course + White Card first.
Insurance (construction all-risk + public liability)
1 week→ 3 days
Don't leave this to the last minute. You can't start any site work without it.
Demolition & Site Prep
Expected: 2–4 weeksActual: 4 weeks
Complete
Groundwork & Slab
Expected: 3–5 weeksActual: 5 weeks
Complete
Framing & Roof
Expected: 3–6 weeksActual: In progress
In Progress
Enclosed / Lock-Up to Fit-Off
Expected: 8–14 weeksActual: Not started
Upcoming
Internal Fit-Off & Finishing
Expected: 6–10 weeksActual: Not started
Upcoming
Completion & Handover
Expected: 2–4 weeksActual: Not started
Upcoming
Expectation vs reality
Before I started, I mapped out a best-case timeline. Here's how it's tracking against reality — and the pattern is the same one every owner-builder I've spoken to describes.
Reality Check
What They Tell You vs What Actually Happens
Phase
"Should take"
Actually takes
Why
Planning & Approvals
2–4 months
3–6 months
CDC/DA takes longer than you think. Engineers have backlogs. Architects need revisions.
Demolition
1 week
2–4 weeks
Asbestos removal, service disconnections, and booking the demo crew all take longer than the actual demolition.
Slab
2 weeks
3–5 weeks
Rain delays, inspection rebooking, cure time. One week of rain can push everything out by two.
Frame to lock-up
6 weeks
8–12 weeks
Window lead times, inspection delays, weather. The frame goes up fast — everything after it is slower than you expect.
Internal fit-off
8 weeks
10–16 weeks
Trade coordination is the killer. One late trade pushes every trade after it. Tiling alone can take 3 weeks.
Completion to OC
2 weeks
3–6 weeks
Service connections, certificate chasing, final inspection rebooking. The last 5% takes 20% of the time.
Every owner-builder I've spoken to says the same thing: add 50% to whatever timeline you think is realistic.
Timelines are based on the founder's 252m² KDR on the Central Coast, NSW and conversations with other owner-builders. Your project will vary.
The delays nobody warns you about
The big delays aren't the dramatic ones. They're the boring, bureaucratic ones that eat weeks without you even noticing:
Weather
You can't pour a slab in the rain. You can't paint in the rain. You can't do external cladding in the rain. One bad week pushes everything out, and the trades you've booked for the following week may not be available again for another 2–3 weeks.
Trade availability
Good trades are booked 4–8 weeks out. If your framing is delayed by 2 weeks, your roofer's window might close and you're waiting another month. This cascading effect is the single biggest cause of blowouts.
Inspection rebooking
Your certifier isn't sitting around waiting for your call. If you fail an inspection or need to reschedule, the next available slot might be 4–7 days away. That's 4–7 days of dead time.
Service connection lead times
Ausgrid, Sydney Water, NBN — each has its own application process and its own timeline. Some take 6+ weeks. If you don't apply early enough, you're waiting for a connection while the house is otherwise finished.
Decision fatigue
This one's on you. Tiles, taps, paint colours, benchtops, handles, light fittings, flooring — hundreds of decisions, each with a lead time. Every decision you delay pushes the trade that needs it. Decide early, decide once.
What I'd tell someone about to start a KDR
If you're reading this before you've broken ground, here's what I wish I'd known:
1
Add 50% to your timeline estimate. If you think 12 months, plan for 18. You'll probably land somewhere in between — and you won't be stressed about it.
2
Book trades 6–8 weeks ahead, not 2 weeks. Especially framing, roofing, and electrical. The good ones are booked out and won't wait for you.
3
Apply for service connections the moment your slab is poured. Some authorities take 6+ weeks. Don't be the person with a finished house and no power.
4
Make all your finish selections (tiles, taps, flooring, cabinetry) before the frame goes up. Lead times on materials are 4–8 weeks. You don't want your tiler waiting because your tiles haven't arrived.
5
Keep a running list of every certificate you need. Start collecting them from the first trade. Chasing paperwork at the end is miserable and delays your OC.
6
Accept that you will lose time. Rain, inspection fails, trade no-shows, material delays — something will go wrong. Build buffer into your plan and your budget so it doesn't break you when it does.
This article will keep updating
As each phase of my build completes, I'll update the timeline above with actual dates, actual costs, and actual lessons. Bookmark this page and check back — or follow the build on our socials.
If you're about to start your own KDR and want to plan it properly from day one, Bildr builds your entire timeline — week by week, trade by trade — from a 2–3 hour AI conversation about your specific project.
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Get a personalised build timeline before you break ground.
Budget, timeline, trade schedule, compliance tracker — all generated from one AI conversation about your specific build.
Disclaimer: Some names, figures, timelines, and details in this article may have been changed, simplified, or fictionalised for illustrative and storytelling purposes. While based on real owner-builder experiences, individual scenarios, costs, and outcomes will vary depending on your location, build type, market conditions, and other factors. This content is general guidance only and should not be relied upon as professional financial, legal, or construction advice. Always consult qualified professionals before making decisions about your build.
A
Alex Snaith
Founder of Bildr. Currently owner-building a 252m² knockdown rebuild on the Central Coast, NSW. This article updates as the build progresses.
Timelines in this article are based on the founder's personal experience on a 252m² knockdown rebuild on the Central Coast, NSW, and conversations with other owner-builders. Every build is different — your timeline will vary based on build size, complexity, location, weather, trade availability, council processes, and dozens of other factors. This article is general guidance only and does not constitute professional construction or project management advice. Always work with your certifier, engineer, and trades to establish timelines specific to your project. All prices are in AUD and inclusive of GST unless stated otherwise.