Best granny flats & home extensions builders in Perth metro

Why it ranks first

With 284 reviews at a 4.9 average, this is the highest-volume, highest-confidence result on the list, built on a reputation for solving installs other trades turn down. Named technicians like Will, James, Matt and Stuart show up repeatedly in reviews for patient, transparent work on everything from compact kitchen hoods to roof-mounted external motor systems.

Pros

• ✓CSIRO-certified BAL-rated roof vents for bushfire zones
• ✓Takes on complex installs competitors decline
• ✓Fast appointment slots and same-day fixes
• ✓Consistent, named technicians praised across reviews

Why it ranks second

Every recent review tells the same story: Rob's team turns up on schedule, finishes on budget, and keeps the site tidy from a laundry refresh through to a 12-week full-house job. It's a smaller review base than the top spot, but the perfect 5.0 average across 50 reviews and consistent daily communication make it a strong, low-risk pick.

Pros

• ✓On-time and on-budget delivery track record
• ✓Clear daily communication throughout the job
• ✓High standard of trades and site cleanliness
• ✓Handles complex older homes and strata requirements

Why it ranks third

Independent Building Advice isn't a builder itself, it's a design and advisory service that pairs clients with vetted builders and stays involved from concept through post-completion inspection. Consultants Behan, Dom, Amanda and Andy are named repeatedly for listening closely and steering projects through complex approvals.

Pros

• ✓Personalised design that can cut build costs through efficiency
• ✓Vetted builder selection matched to budget and needs
• ✓Support from pre-design through to final inspection
• ✓Clients report savings of 20% or more versus major builders

Why it ranks fourth

Kev Renovations holds a perfect 5.0 across 20 reviews, with clients in the Perth Hills praising the team for consulting at every decision point during months-long jobs. The confidence is medium given the review count, but the pattern of on-time, on-budget delivery on structurally complex homes is consistent.

Pros

• ✓Perfect 5-star record across all reviews
• ✓Client consulted at every major decision point
• ✓Delivers on quoted timelines and budgets
• ✓Handles structural challenges and non-plumb older homes

Why it ranks fifth

Willetton Cabinets has an in-house factory and a track record of quality design work when jobs go smoothly, backed by owner Sam and supervisor Travis. It's best suited to smaller, well-scoped projects where expectations are managed closely up front.

Pros

• ✓Custom cabinetry built to exact space and spec
• ✓Long-term aftercare, including free hinge replacement after 20 years
• ✓Experienced project management under Travis
• ✓In-house factory gives design flexibility

Why it ranks sixth

Marcus personally oversees every job at MJD Projects, from selection through handover, and reviewers over an eleven-month run gave nothing but five stars. One reviewer, a tradie himself, called out the quality and attention to detail as exceptional, though the review base is still small.

Pros

• ✓Owner-managed oversight on every project
• ✓Transparent communication about decisions and costs

Why it ranks seventh

Add Value Building Group earns consistent praise for Ciaran's hands-on leadership, with clients and trade partners alike crediting the team for hitting deadlines and budgets. The review count is modest, but the willingness to return and fix issues months after handover stands out.

Pros

• ✓Consistent on-time and on-budget delivery
• ✓Ciaran's direct communication and professionalism
• ✓Well-organised, professional site management
• ✓Responsive support even after handover

Why it ranks eighth

Lasting Impressions runs a tight, family-based team of licensed trades, including in-house electricians, and reviewers highlight speed and fair pricing on kitchen and bathroom work. One early complaint about slow quoting is worth noting against an otherwise solid record.

Pros

• ✓Custom cabinetry made on-site
• ✓Licensed electricians as part of the core team
• ✓Family-run business with longstanding staff
• ✓Delivers on budget and to timeline

Why it ranks ninth

Every one of Petit Home Improvement's 12 reviews is five-star, with Geoff Petit's team praised for finishing extensions and second-storey additions ahead of schedule even through Covid delays and council approval hurdles. The review count is small, but the consistency of the feedback on minimising disruption in occupied homes is notable.

Pros

• ✓Delivers projects early and within budget
• ✓High-quality finishes and attention to detail
• ✓Minimises disruption while clients remain in the home
• ✓Clear communication and cost control

Why it ranks tenth

Nautilus Co is led by Brett Walters, a licensed plumber and tiler, and all 17 reviews give five stars for his craftsmanship and attention to detail on bathroom and kitchen work. The all-in-one plumbing, tiling and building service is a genuine point of difference for bathroom-focused extension work.

Pros

• ✓All-in-one plumbing, tiling and building service
• ✓Licensed plumber and gas fitter
• ✓Meticulous attention to detail
• ✓On-time delivery and cost awareness

Why it ranks #11

SOL Construction is led personally by Nick Del Borrello, praised in most reviews for hands-on supervision and finish quality on custom builds and SDA villas. One recent review alleging delays and overcharging stands in contrast to the older glowing feedback, so the mixed signal is worth weighing.

Pros

• ✓Owner-led projects with personal supervision
• ✓Specialist experience in custom builds and SDA villas
• ✓Strong finish quality and attention to detail
• ✓Flexible and listens to client needs

Why it ranks #12

Persona Homes attracts repeat clients who return for multiple builds, with reviewers pointing to design flexibility, budget control and reliable handover timelines. Site conduct and defect follow-up have been sticking points for a portion of reviewers, which pulls down an otherwise capable track record.

Pros

• ✓Long-term track record with repeat clients
• ✓Direct engagement from designers and supervisors
• ✓Custom design work with budget control
• ✓Consistent on-time completion

Why it ranks #13

Peter's shower regrouting and tiling work draws praise for finish quality and a clean site, though the evidence is thin: just three five-star reviews spread over seven years. Useful for a small, well-defined tiling job rather than a full extension.

Pros

• ✓Meticulous tiling finishes
• ✓Keeps work sites clean and tidy

Why it ranks #14

Eldridge Homes is built around Jensen's hands-on supervision and honest, transparent pricing with documented variations, though the review base is limited to three. Clients who've used the business describe a design-led approach and repeat satisfaction.

Pros

• ✓Jensen's on-site presence and personal involvement
• ✓Transparent pricing with documented variations

Why it ranks #15

Perth Homes Construction holds a perfect five-star average across 16 reviews, with staff member Bander singled out for going beyond the brief on extension design thinking. Verification and completeness scores are lower here, so it's worth doing your own due diligence alongside the review record.

Pros

• ✓Perfect 5-star rating across all reviews
• ✓Keeps projects on budget
• ✓Honest, upfront advice
• ✓Staff praised for going above and beyond