Renovate when the existing structure is sound and you only want to change how the inside works. Extend when the house is sound but too small, and the block has room in the right direction. Knock down and rebuild when the bones are failing, the floor plan fights the site, or the compromises needed to keep the old building cost more than starting again. On the Sunshine Coast the deciding factor is usually not taste — it is the condition of the existing slab, frame and roof, the orientation of the block, and what the Sunshine Coast Planning Scheme 2014 or the Noosa Plan 2020 will let you build. This guide sets out how to work through those three options in order, what each one triggers in approvals and contracts, and where the real money and time go.
The short answer: work through the three options in order
Most people arrive at this question having already fallen in love with one answer. The useful discipline is to test all three in sequence, cheapest first, and only move up when the cheaper option genuinely fails.
Start with renovate. Can you get the result you want by reworking what is already there — moving a wall, opening the rear to the north, redoing the kitchen and bathrooms, replacing windows and cladding? If yes, that is almost always the fastest and least regulated path. If the house is fundamentally the wrong size, move to extend: an extension keeps the parts of the building that still work and adds the floor area you are missing, and its price depends less on the new work than on the condition of what you are attaching it to.
Only if both of those fail should you price a knock down and rebuild. That failure usually looks like one of four things: the frame or slab is compromised, the house sits wrong on the block and cannot be reoriented, the level changes make an extension structurally silly, or the sum of the compromises produces a house nobody would design on purpose.
Tom Roebuck has been running residential jobs on the Sunshine Coast for more than 20 years, and the honest position is this: we build either way, so the only thing worth arguing about is which option gets you a house you would still be happy with in fifteen years.
The three-way decision matrix
Use this to compare the three paths on the four things that actually differ. The cost column deliberately describes drivers rather than dollar figures, because a rate per square metre quoted without knowing your slab, your slope and your finishes is worse than no number at all. For sourced cost ranges, see cost to build a house on the Sunshine Coast and renovation cost per square metre in Queensland.
| Option | What drives the cost | What drives the timeline | Approval path | Disruption |
|---|---|---|---|---|
| Renovate within the existing footprint | Number of wet areas touched, whether plumbing and structural walls move, and what is found once linings come off. Roof, slab and external walls stay, so you carry no new footing or frame cost. Building work valued over $3,300 must be contracted with a QBCC-licensed contractor, and QBCC states that home warranty insurance “only needs to be paid on projects valued at $3300 and above”. | Trade sequencing in a confined space, not approvals. Waterproofing cure times, tiling, joinery and appliance lead times usually control the critical path. Latent conditions behind old linings are the main variable. | Often building approval only, and sometimes none. Sunshine Coast Council’s guidance is that “a private building certifier can advise whether you need a development building work permit”, and that “some minor building work may be accepted development or exempt building work”. A planning application is only triggered if an overlay or character control applies. | Highest per week if you stay in the house. You are living inside a working site, with dust, noise and no kitchen or bathroom for stretches of it. |
| Extend | New floor area carries footings, frame, roof and the tie-in back to the existing building. Slope, site access and the load capacity of the existing structure drive the number more than the finishes do. Re-roofing or re-stumping the old half to match is a common and underestimated cost. | Longer than a renovation, because design, structural engineering and energy compliance documentation sit in front of construction, and a development application adds an assessment period wherever the extension breaches setbacks, height or site cover. | Building approval, plus a development application to Sunshine Coast Council or Noosa Shire Council where the work does not meet the accepted development requirements of the Sunshine Coast Planning Scheme 2014 or the Noosa Plan 2020. QBCC lists five mandatory inspection stages for a dwelling — excavation, footing, slab, frame and final — and these apply to the new work. | Moderate to high. The new zone can usually be sealed off, but the tie-in weeks — roof penetration, services, matching floor levels — are the hard part and often force you out. |
| Knock down and rebuild | The largest total spend of the three, because you pay for demolition, service disconnections and a full new slab, frame, roof and services rather than reusing any of them. What you stop paying for is working around existing structure: no allowance for the unknown behind old linings, and no compromise imposed by a wall that has to stay. Contracted as a New Home Construction Contract under the QBCC framework. | Longest end to end, because the stages run in sequence rather than overlapping: demolition, then approvals, then full construction. Under QBCC’s contract rules your contractor must give you the commencement notice within 10 business days of work starting on site. | The most steps. Demolition approval where the planning scheme requires it, service disconnections, a new building development approval, and a development application where overlays or siting provisions apply. Business Queensland states that a building development approval “is needed before construction can start on most types of domestic building work”. | Lowest day to day, because you move out — but it runs longest and you carry rent or alternative accommodation for the whole period. The Queensland Home Warranty Scheme includes a sub-limit of “a maximum of $5,000 for alternative accommodation, removal costs, storage costs”, rising to $10,000 where optional additional cover has been taken out, and that is a claim limit, not a budget. |
Two things fall out of that table that people rarely expect. First, the disruption column runs the opposite way to the cost column — the cheapest option is the one that makes your life worst while it is happening. Second, the approval path, not the construction, is usually what determines whether you finish this year or next.
When renovating is the right call
Renovation wins when the structure is sound and the problem is the layout, the finishes, or the way the house meets the outdoors. On the coast that last one is the most common brief we get: a 1990s or 2000s house with the living areas facing the street and the good aspect wasted on bedrooms and a laundry.
You are a good candidate if the slab is level and uncracked, the frame is straight and termite-free, the roof has life left in it, and the house already sits in roughly the right place on the block. Under those conditions your entire budget goes into the parts you will see and use every day rather than into structure nobody will ever look at.
The pressure test is what happens when the linings come off. Older Sunshine Coast housing stock hides three recurring problems: under-braced walls that were never designed for the opening you now want, waterproofing that failed years ago behind a serviceable-looking bathroom, and electrical or plumbing runs that have to be replaced wholesale rather than extended. None of these are reasons not to renovate. They are reasons to carry a contingency and to use a builder who prices allowances honestly. Our renovation building service pages set out how we scope that work before a price goes on paper.
Contractually, renovation work sits in one of two QBCC categories. QBCC sets a Level 1 Renovation, Extension and Repair Contract for work priced from $3,301 to $19,999, and a Level 2 contract for work priced at $20,000 and over. For a Level 2 contract, QBCC requires the contractor to give the homeowner “a QBCC-approved consumer building guide before the homeowner signs the contract”. If a builder wants to start a $60,000 bathroom-and-kitchen job on a quote and a handshake, that is a licensing and contract problem before it is anything else.
When extending is the right call
Extending wins when the house is structurally sound but simply too small, and the block has capacity in the direction you need it. That capacity is a planning question as much as a physical one — a five-metre side yard is no use to you if the setback, height or site cover provisions of the planning scheme say you cannot build in it without a development application.
The Sunshine Coast Planning Scheme 2014 was adopted by council on 14 April 2014 and commenced on 21 May 2014, and Sunshine Coast Council describes it as regulating “the way land, buildings and structures are used and developed on the Sunshine Coast”. Noosa Shire Council administers the separate Noosa Plan 2020. Which one applies depends purely on which local government area your lot sits in — Coolum Beach and Yaroomba fall under Sunshine Coast Council, while Noosa Heads and the Noosa hinterland sit under Noosa Shire Council. We cover the mechanics in building approvals on the Sunshine Coast and in Noosa.
The technical trap in extensions is the junction. Every extension has a seam where new work meets old, and that seam is where the budget goes: matching floor levels across a slab-on-ground original and a suspended new floor, tying a new roof into an existing one without creating a valley that leaks in a February downpour, and getting old structure to carry loads it was never designed for.
Extending upwards deserves its own warning. A second storey on a single-storey house means an engineer must confirm the existing footings and frame can carry the new load, and frequently the answer is that they cannot without underpinning or new internal structure. That does not kill the idea, but it can shift the arithmetic decisively towards a rebuild. On a block that falls away — common through Ninderry, Yaroomba and the Noosa hinterland — retaining and engineered footings land on both sides of the comparison, so price them before assuming an extension is cheaper.
When knocking down and rebuilding wins
A rebuild wins when the compromises stack up. Individually each one looks tolerable — the ceilings are a bit low, the bedrooms are on the view side, the roof needs replacing in five years, the slab has a step in the wrong place. Together they produce a house that costs renovation money and delivers a compromised result.
The clearest signals we see on the Sunshine Coast are a slab with structural cracking or significant differential movement, extensive termite or moisture damage to the frame, asbestos-containing materials distributed through the building rather than isolated in one area, and a house whose orientation cannot be fixed without effectively rebuilding it anyway. Add any case where you want a fundamentally different envelope — more height, a different roof form, a pool integrated into the ground floor — and the rebuild case makes itself.
The counter-intuitive part is what your money buys. A rebuild is a bigger total, but every dollar goes into new structure rather than into patching around old: no allowance for the unknown behind the linings, no premium for working around existing finishes, no compromise imposed by a wall that has to stay. Whether that trade is worth it is an arithmetic question to answer on your own house, with real prices in front of you. See our knock down rebuild service for how we structure that comparison, and renovate or knock down rebuild for the head-to-head.
One practical caution: demolition is not a free action. You will need service disconnections arranged with the relevant authorities, an asbestos assessment and, where the material is present, licensed removal. Whether the demolition itself needs planning approval depends on your zone, your overlays and whether any character or heritage provisions attach to the building. Ask your certifier and the council before you book a machine.
What the site decides for you
On the Sunshine Coast, the block often makes the decision before the building does. Sunshine Coast Council publishes development fact sheets covering acid sulfate soil, bushfire management, flood information relevant to building work, earthworks, retaining walls, vegetation clearing requirements and secondary dwellings, among others — that list is a fair map of the constraints that turn up on coastal and hinterland lots here. Noosa Shire Council separately publishes flood mapping and coastal hazards mapping for its shire.
Those constraints affect the three options unevenly, and this is the part most people miss. A renovation inside an existing footprint usually does not trigger an overlay assessment, because you are not changing the building’s relationship to the hazard. An extension may trigger one, because you are adding floor area — possibly into a flood or bushfire-affected part of the lot. A rebuild almost certainly triggers a full assessment, because you are starting from scratch and current provisions apply to the whole building rather than just the new bit.
That asymmetry cuts both ways. If your house sits below a current flood or storm tide level, a rebuild forces you to lift it to comply — an expense, but also a permanent fix a renovation would never deliver. If your lot is heavily vegetated or steeply sloped, a rebuild means engineering the whole site rather than a corner of it. Get an informed answer on your specific lot before you compare prices, not after.
What each option means for your contract and your protection
The three options are not just different buildings. They sit under different contract frameworks and different consumer protections.
Licensing first. QBCC requires a licence for building work valued over $3,300, with lower or nil thresholds for specific work — over $1,100 where the work involves hydraulic services design, and any value at all for plumbing and drainage, gas fitting, fire protection, building design and site classification. An owner carrying out work on their own property is exempt where that work is valued at no more than $11,000, or beyond that under an owner-builder permit. Check the licence before the quote: our guide on how to check a QBCC licence walks through the register search.
Deposits are capped by contract value. QBCC sets the maximum deposit at 10% of the contract price for Level 1 contracts ($3,301 to $19,999) and 5% for Level 2 contracts ($20,000 and over), with up to 20% permitted where substantial customised work or prefabrication is carried out away from the site and represents more than half the contract value. QBCC warns that if you pay more than the lawful maximum, “you will not be entitled to recover the excess you have paid in the event you need to make a claim under the Queensland Home Warranty Scheme for refund of deposit”. You also get a cooling-off period: QBCC sets it at five business days, beginning the day after you receive a signed copy of the entire contract including any plans and specifications, and withdrawing during it costs you $100 plus an amount equal to any out-of-pocket expenses the contractor reasonably incurred before you withdrew.
Insurance cover matters most on a rebuild, because the numbers are biggest. QBCC caps Queensland Home Warranty Scheme cover at $200,000 for each category of loss covered, increasing to $300,000 where optional additional cover has been taken out. Cover runs 6 years 6 months from whichever is earliest of the date you pay the premium, the date you agree to a contract, or the date work starts. For a structural defect you must first become aware of it within that 6 years 6 months and make the claim within 3 months after the day you first become aware; for a non-structural defect you must first become aware within 6 months after the day the work is substantially complete and make the claim within 7 months after that same date. If your rebuild is a substantial one, that $200,000 ceiling is worth knowing about before you sign, not after.
Finally, variations. QBCC requires that before the contractor commences variation work, “you must present the variation to the home owner in writing” and “the home owner must agree to it in writing”, with a written copy given to the owner before the earlier of the variation work starting or 5 business days from the day both parties agree. QBCC says failing to properly and accurately record and approve variations before they are implemented “is one of the most common causes of serious building disputes”. Renovations produce the most variations because they produce the most surprises, which is exactly why the contract framework matters more on a renovation than most people assume.
A worked example: Grandview Drive, Coolum Beach
Our Grandview Drive project at Coolum Beach is the clearest illustration we have of the middle path done properly. It was delivered as a major renovation and remodelling of an existing home rather than a rebuild, and it won three awards at the Master Builders Queensland 2025 Sunshine Coast Housing & Construction Awards, presented on 15 August 2025 at The Events Centre, Caloundra: Home Renovation/Remodelling Project over $1 million, Best Residential Swimming Pool, and Best Use of Innovation.
The reason that job stayed a renovation is worth stating plainly: the existing structure could carry the new work, and the site’s aspect was already right. Keeping the building meant the budget went into the pool, the innovation and the finished result rather than into replacing structure that was doing its job. Had the building been the wrong shape or the aspect wrong, the same money would have bought a much poorer outcome. You can see the detail on the Grandview Drive, Coolum Beach project page.
We work with architects including K Architecture and Reitsma & Associates on jobs of that scale, and the renovate-versus-rebuild call is one we prefer to make jointly with the designer and an engineer, on site, before anyone draws anything.
How to make the decision without guessing
Get four things before you commit. A structural assessment of the existing slab, frame and roof from an engineer, not an opinion from a builder standing in the driveway. A planning check on your specific lot against either the Sunshine Coast Planning Scheme 2014 or the Noosa Plan 2020, including every overlay that applies. A concept design tested against both a renovation or extension scenario and a rebuild scenario. And a builder’s price against each, with allowances and exclusions written out rather than a single number.
That preliminary work costs money and takes weeks. It is also the cheapest insurance available on a decision of this size, and it is the step people skip most often. A price built on an engineer’s report and a planning check is a price that can hold; a price built on a walk-through is a starting position.
If you would like that assessment done on your Sunshine Coast or Noosa property, call Roebuck Concepts on 0477 333 386 or come and see us at Unit 1/18 Lomandra Place, Coolum Beach.
Frequently asked questions
Is a knock down rebuild cheaper than a renovation on the Sunshine Coast?
Not in total. A rebuild carries demolition, service disconnections and full new structure, so the headline number is bigger. What it removes is the cost of working around existing structure, the allowances for unknowns behind linings, and the compromises imposed by walls that have to stay. Whether that trade is worth it depends on the condition of your existing building and how badly it fights the site, and the only way to settle it is to price both options on your own house.
Do I need council approval to demolish a house on the Sunshine Coast?
It depends on your zone, your overlays and whether any character or heritage provisions attach to the building under the Sunshine Coast Planning Scheme 2014 or the Noosa Plan 2020. You will separately need service disconnections and, where asbestos is present, licensed removal. Sunshine Coast Council’s guidance is that “a private building certifier can advise whether you need a development building work permit”, and that is the right first call.
What contract should a renovation be under in Queensland?
QBCC sets a Level 1 Renovation, Extension and Repair Contract for work priced from $3,301 to $19,999, and a Level 2 contract for work priced at $20,000 and over. For a Level 2 contract the contractor must give you a QBCC-approved consumer building guide before you sign the contract, and QBCC sets the maximum deposit for a Level 2 contract at 5% of the contract price.
Does a renovation get home warranty insurance in Queensland?
Yes. QBCC states that home warranty insurance “only needs to be paid on projects valued at $3300 and above”, and that the insurable value excludes the QBCC premium itself. Cover runs 6 years 6 months from whichever is earliest of the date the premium is paid, the date you agree to a contract, or the date work starts, and is capped at $200,000 for each category of loss covered, or $300,000 where optional additional cover has been taken out.
How many building inspections are required in Queensland?
QBCC lists five mandatory inspection stages for a dwelling: excavation, footing, slab, frame and final. Business Queensland notes that inspection requirements are addressed in section 44 of the Building Regulation 2021 and in the building development approval itself, so the approval issued for your particular job is the document that sets out exactly what must be inspected and when.
Will building codes change before I start?
Possibly. The ABCB published NCC 2025 on 1 May 2026 and lists Queensland’s adoption date for it as 1 May 2027. If your project spans that date, ask your designer and certifier which edition your approval will be assessed under, because it affects energy performance documentation and therefore your design.
Which councils cover the Sunshine Coast and Noosa?
Two. Sunshine Coast Council administers the Sunshine Coast Planning Scheme 2014, which council adopted on 14 April 2014 and which commenced on 21 May 2014. Noosa Shire Council administers the Noosa Plan 2020. Suburbs such as Coolum Beach, Yaroomba, Pelican Waters and Cotton Tree sit under Sunshine Coast Council; Noosa Heads, Marcus Beach and the Noosa hinterland sit under Noosa Shire Council.