Best builders & renovation companies in Stirling & Scarborough, WA (2026)
Table of Contents
These are the best-rated builders and renovation companies working Stirling and Perth’s north-coastal corridor: Scarborough, Karrinyup, Balcatta, Osborne Park, Innaloo and Trigg. They’re ranked on real Google reviews, not on who paid us. Building is a service-area trade, run off a ute, a site office and a project schedule rather than a shopfront, so this is an honest read of the operators genuinely working this stretch, whether you’re after a knock-down-rebuild, a second storey, a beachfront renovation, or a kitchen and bathroom refresh. One thing to know up front: builders collect far fewer Google reviews than plumbers or pest controllers, because most people build or renovate once or twice in a lifetime, so the review counts here look smaller than on our other trade pages. The corridor has its own build profile: older brick-and-tile homes in Karrinyup, Balcatta and Innaloo suit knock-down-rebuilds and full renovations, while beachfront and near-coastal properties around Scarborough and Trigg add salt-air durability and coastal-building-code considerations to the mix. Below you’ll find what building and renovation work actually costs in 2026, why WA caps a builder’s deposit at 6.5%, what home indemnity insurance protects you from, and a quick checklist before you sign anything.
Featured builders
These spots are for Stirling and north-coastal builders and renovators who want to stand out on this page. None are taken yet, so the full review-ranked list is right below. That ranking is earned off Google reviews and never for sale. Are you a registered builder or renovation company working Scarborough, Karrinyup or Osborne Park? Featured spots start at $50 a year.
How we ranked these builders
- Google reviews do the ranking. We start with every builder’s live Google star rating and the number of reviews behind it, pulled fresh from Google Maps.
- Rating, weighted by volume. A 5.0 off one or two jobs isn’t proof yet, so we weight the score by review count. A proven rating from a solid client base counts for more than a perfect score from a handful, which is why Welch Homes, with the deepest 5.0 record on the page, leads the list. Homebuilders IQ – Perth carries by far the biggest review base of anyone here (219) at a still-strong 4.8, and sits just below the 5.0-rated builders under our rating-first rule.
- Fewer reviews than other trades, on purpose. People build or renovate rarely, so builders gather far fewer Google reviews than a plumber or a pest controller doing dozens of jobs a week. A builder with 30-50 genuine reviews already has a strong track record for this trade. We’ve judged these on the builder yardstick, not against the review counts you’d see on our plumbing or pest control pages.
- Serving the north-coastal corridor, honestly framed. Building is a mobile trade and most builders list a head office rather than a shopfront on the strip. Homebuilders IQ – Perth is based right on Cedric St in Stirling, and Renovation Capital works out of Osborne Park; the rest are established Perth builders who regularly take on jobs across the corridor. We’ve flagged the locally based ones.
- Builders, not tradies or suppliers. We only counted businesses doing the actual building or renovation project management, not individual trades (electricians, tilers) or building-material suppliers.
Welch Homes
Welch Homes backs a perfect five-star average with the deepest genuine review base of any 5.0-rated builder on this page, covering new builds and renovations across Stirling and the north-coastal suburbs.
Amerex Renovations
Amerex Renovations holds a perfect five-star average across a solid 44 reviews, with a focus on custom home renovations for the established brick-and-tile pockets of the corridor.
Homebuilders IQ – Perth
A genuinely local outfit, based right on Cedric Street in Stirling, and by far the deepest review base of any builder on this page at 219 reviews, backed by a strong 4.8 average.
5.0(7 reviews)
5.0(5 reviews)
4.8(58 reviews)
4.8(37 reviews)
4.6(17 reviews)
4.5(43 reviews)
A note on the order: builders earn far fewer Google reviews than most trades, so the counts here are smaller than on our plumbing or pest pages, and that’s expected, not a red flag. We weight the star rating first and use review volume as the tie-break, the same rule as every other trade page on this site.
What building and renovation work actually costs in Stirling & the north-coastal suburbs (2026)
Real ranges for the Perth metro area in 2026. Always get at least two written, like-for-like quotes.
| Service | Typical cost | What changes the price |
|---|---|---|
| Bathroom renovation (full strip-out and refit) | $18,000-$40,000 | Layout changes, waterproofing, tiling area, fixtures and tapware, moving plumbing, second-storey access |
| Kitchen renovation (full) | $22,000-$60,000 | Cabinetry and stone, appliances, moving services, structural wall removal, high-end finishes |
| Room addition / rear extension (ground floor) | $2,500-$4,500 / m² | Site access, footings on sandy or limestone ground, matching the existing roofline and brickwork, finishes |
| Second-storey addition | $280,000-$600,000+ | Engineering, existing footings, staying in the house during the build, structural upgrades, ocean-view glazing |
| Whole-house renovation (cosmetic to structural) | $120,000-$400,000+ | Extent of structural work, kitchen and bathrooms, re-wire and re-plumb, age and condition of the home |
| New custom home (build only, per m²) | $2,200-$4,000+ / m² | Single vs double storey, spec level, block slope and soil, coastal exposure, bespoke design |
| Knock-down-rebuild (demolition + new home) | $450,000-$900,000+ | Demolition and site clearing, asbestos removal on older homes, home size and spec, coastal block |
| Granny flat / ancillary dwelling | $120,000-$260,000 | Size, kitchen and bathroom fit-out, connecting services, site access, whether it’s transportable or built on site |
| Patio, alfresco or outdoor living | $8,000-$40,000 | Size, roof type, decking, flooring, whether it ties into the house structure |
| Home indemnity insurance (builder arranges, on work over $20k) | Built into contract | Contract value; legally required in WA and passed on in the build price |
The northern suburbs carry their own building conditions worth pricing in. The established suburbs, Duncraig, Kingsley, Woodvale, Greenwood, Padbury, Hillarys and Sorrento, are full of 1970s to 1990s brick-and-tile homes that renovate and extend well, but on an older home budget for surprises once the walls open up: asbestos in eaves, fences and old sheeting, dated wiring and plumbing that a good builder will flag before you sign, not after. Out in the growth corridor, Banksia Grove, Tapping, Butler, Alkimos, Eglinton and Yanchep, the work is mostly new homes and knock-down-rebuilds on sandy coastal blocks, where site works, footings and fill can add real money on a sloping or reactive site. Anywhere near the coast, from Ocean Reef and Mullaloo up to Mindarie and Alkimos, salt air is a genuine factor, so quality external fixings, finishes and glazing that stand up to it are worth paying for rather than cutting. And whatever the job, the big cost driver is scope creep: every change once the build starts is a variation, and variations are where a tidy fixed price quietly becomes an open cheque. Lock the scope and the finishes down in the contract before a shovel hits the ground.
Don’t get ripped off: red flags
- Not a registered builder. In WA, residential building work over a set value must be carried out by a builder registered with the Building Services Board. Ask for the registration number and check it on the Building and Energy (DMIRS) register before you sign. An unregistered “builder” leaves you with no proper comeback.
- A deposit over the legal cap. Under WA’s home building contract rules the deposit is capped at 6.5% of the contract price. Anyone asking for 10, 20 or 30 per cent up front is breaking the rules and putting your money at risk. Walk away.
- No home indemnity insurance. For residential work over $20,000, the builder must take out home indemnity insurance and give you the certificate before they take a deposit or start. It protects you if they die, disappear or go insolvent mid-build. No certificate, no start.
- No written contract, or a vague one. Building work over the WA threshold needs a proper written contract with a fixed scope, a fixed price or a clear pricing basis, and a schedule of progress payments. A one-page quote with “the rest TBC” is how disputes start.
- Progress payments not tied to stages. You should pay in stages against work completed, deposit, slab, plate height, lock-up, fit-out, practical completion, not big lump sums ahead of the work. Paying well ahead of the build leaves you exposed if it stalls.
- The quote is thousands cheaper than everyone else. On a build, the lowball quote is usually the most expensive in the end, either it’s missing scope that comes back as variations, or the finishes are stripped down to hit the number. Compare quotes on identical scope and specification.
- Cash discounts and “start Monday” pressure. A builder pushing a cash deal, no contract, or urgency to sign today is a builder to avoid. Good builders have a waitlist and work to a contract.
- Vague on the building permit. Nearly all structural work needs a building permit from the local council or a private certifier. If a builder shrugs off permits or offers to “do it without”, you wear the risk when you sell or insure.
- No allowances spelled out. Watch for “prime cost” and “provisional sum” allowances set artificially low, for tiles, tapware, flooring or site works, so the headline price looks sharp and blows out later. Ask what each allowance assumes.
- Won’t give references or show finished work. A builder proud of their work will happily point you to a recent finished home or a client to ring. Reluctance is a tell.
Before you hire: quick checklist
- Registered builder. Confirm the builder or company holds current registration with the WA Building Services Board and check the number on the Building and Energy register. It’s a legal requirement for residential work, not a nice-to-have.
- Written contract on the right terms. Get a proper written building contract with a fixed scope, the price or pricing basis, the progress-payment schedule and the finish allowances all spelled out before any money changes hands.
- Deposit within the cap. Check the deposit is no more than 6.5% of the contract price, the WA legal maximum. Anything higher is a warning sign.
- Home indemnity insurance certificate. For work over $20,000, sight the home indemnity insurance certificate before you pay a deposit or let work start.
- Building permit sorted. Confirm who’s obtaining the building permit and that it’s in place before structural work begins.
- Right builder for the job. Match the builder to the project, a volume new-home builder, a custom builder and a renovation specialist each suit different work. Ask to see a recent finished job like yours.
- Allowances and variations. Understand every prime-cost and provisional-sum allowance, and how variations are priced and approved, before you sign. This is where budgets blow out.
- Recent, specific reviews and references. Look for recent reviews that mention the actual build or reno, and ask for a client or two you can call. A steady stream beats one old burst of five stars.
Frequently asked
How did you rank these builders?
By their live Google star rating and the number of reviews behind it, pulled from Google Maps. We rank by star rating first, and break ties by review volume, which is why Welch Homes (5.0 from 95 reviews) leads the page ahead of Homebuilders IQ – Perth, which actually has the biggest review base on the page (219) at a strong 4.8. Building is a service-area trade, so rather than insisting every business sits inside the cluster, we checked each one genuinely services Stirling and the north-coastal suburbs, and flagged the locally based operators (Homebuilders IQ – Perth, Renovation Capital).
Which areas does this cover?
Stirling, Scarborough, Karrinyup, Balcatta, Osborne Park, Innaloo and Trigg. Every business on this page was checked to genuinely service this stretch of Perth’s north-coastal corridor.
Are these paid placements?
No. This list is ordered on Google review data. Businesses can pay for a “Featured” spot at the top, which is clearly labelled, but paying never changes the review-based order below. As of this update, no spots are sold.
Why are the review counts lower than your other trade pages?
Because building is a once-or-twice-in-a-lifetime purchase, so builders simply don’t collect the volume of Google reviews a plumber or pest controller does over the same period. A builder with 20 or 30 genuine reviews already has a strong record for this trade. We weight for that, and we judge these on the builder yardstick rather than against the counts you’d see on our plumbing pages.
Does my builder have to be registered in WA?
Yes. Residential building work over a set value in Western Australia must be carried out by a builder registered with the Building Services Board, administered by Building and Energy within DMIRS. You can check a builder’s registration on the public register. Always confirm registration before you sign, and be wary of anyone who can’t give you a number. This is general information, not legal advice, so check your specific job with Building and Energy WA if you’re unsure.
How much deposit can a builder ask for?
Under WA’s home building contract rules, the deposit on a residential building contract is capped at 6.5% of the contract price. If a builder asks for more up front, that’s a warning sign. After the deposit you should pay in stages against completed work, not in large lump sums ahead of the build. Again, general information rather than legal advice, so check the current rules with Building and Energy WA.
What is home indemnity insurance and do I need it?
Home indemnity insurance protects you, the owner, if your builder dies, disappears or becomes insolvent before the work is finished or a warranty issue arises. In WA it’s required for residential building work over $20,000, and the builder must arrange it and give you the certificate before taking a deposit or starting work. Don’t let a build begin without sighting that certificate.
Should I get a fixed-price contract?
For most home builds and renovations, a fixed-price contract on a clearly defined scope is the safest way to keep control of your budget. The catch is variations: any change once the build starts is priced as a variation, and that’s where a tidy fixed price can blow out. Lock the scope, the finishes and the allowances down in the contract before work begins, and make sure the contract sets out how variations are priced and approved.
How often is this page updated?
Monthly. Ratings and review counts move, new builders earn their spot, and we re-pull the data so the list stays honest and current. As northern-suburbs builders build up reviews, expect this list to shift.
Are you a builder in Stirling or the north-coastal suburbs?
Get in front of homeowners who are ready to build or renovate. Claim your free listing, or ask about a Featured spot on this page.
Last updated: July 2026