Vetted, listed for free

Find Vetted Custom Granny Flat Builders in Your Area

A custom build offers ultimate flexibility. The first step is finding a local, licensed builder who understands your vision.

A custom build offers ultimate flexibility. The first step is to find a local, licensed builder who understands your vision. Select your state below to see who is active in your area.

Is it worth the premium?

The “Turnkey” Premium

Why a managed build costs more, and when that extra is money well spent.

You are paying for risk management

A custom builder charges a premium (typically a 20 to 30% margin), but that premium covers project management and risk: workplace safety, trade coordination and the mandatory 6-year structural warranty (Home Building Compensation Fund). If you are time-poor or inexperienced, this premium is often worth it.

Directory disclaimer: This is a curated list of Australian builders specialising in secondary dwellings, listed for free to help you start your research. We verify that businesses appear active and reputable, but The Granny Flat Guide does not endorse or guarantee their work. Do your own due diligence, check licences, and request insurance certificates before signing.

Granny Flat Solutions

Sydney / Coast

$$$

NSW custom builder that lodges CDC/DA in-house. High-end bespoke designs; confirm site-cost allowances on sloping or access-constrained lots before you treat the display price as turn-key.

Award WinningCustom DesignCDC/DA help

02 9481 7443

Cubitt’s Granny Flats

NSW Wide

Operating since 1994, Cubitt’s is one of the only builders serving regional NSW. Known for reliable, classic designs and fixed-price contracts.

Family OwnedCountry NSWClassic Styles

1300 721 150

Backyard Grannys

Newcastle / Hunter

Newcastle’s dedicated specialist. They do not build main homes, only granny flats, so project management stays on secondary dwellings.

SpecialistHunter ValleyGranny flats only

02 4947 2800

5 Star Granny Flats

Sydney Metro

Offers a massive display village in Seven Hills. Great for investors looking for standard, proven designs with fast turnaround times.

TurnkeyFast BuildShowroom

1300 843 900

Rescon Builders

Sydney

Specialises in rental-oriented builds with a streamlined process. Timeline to a tenant still depends on approvals, site works and the local rental market.

InvestorsRental buildsStreamlined

1300 044 863

Acrow Investments

Central Coast

Central Coast locals. They excel at difficult sites and sloping blocks that major volume builders often reject.

LocalSloping BlocksCustom

02 4323 3223

Premier Homes (Vic)

Bayswater

$$$

Market leaders in Dependent Person Units (DPUs). They have a large display village and offer high-end finishes.

DPU ExpertsDisplay VillageFamily Homes

03 9761 6699

Superior Granny Flats

VIC Wide

Offers both transportable homes and traditional slab-on-ground builds. Flexible options for difficult access sites.

RelocatableConcrete SlabCustom

03 9720 0141

Todd Devine Homes

Melbourne

$$$

High-quality transportable homes and granny flats. Popular for retirement living and holiday parks.

TransportableLifestyleRetirement

03 9720 1686

Dependable Granny Flats

Melbourne

Focuses on accessibility and elderly-care designs. They help with Victorian planning-permit paperwork; council still decides the outcome.

Disabled AccessPermit helpOne Stop

03 9800 2777

Willow Grove Homes

Mornington

Mornington Peninsula specialists. Beautiful weatherboard-style relocatable homes perfect for coastal blocks.

CabinsPeninsulaRelocatable

03 5979 1197

Granny & Co Homes

Brisbane

$$$

Premium Brisbane custom builder using in-house architects for small-home designs. Whether it lifts sale value depends on the lot, finish and local market.

ArchitecturalCustomDesigner

07 3180 2681

Vision Granny Flats

Brisbane / GC

Investor-focused builds with low-maintenance finishes. Yield depends on your rent, vacancy and costs; model the numbers before you treat a brochure figure as income.

InvestorsRentalsTurnkey

1300 096 878

Superior Granny Flats QLD

SEQ Wide

Operating for over 30 years. A safe pair of hands for standard designs and reliable construction in SEQ.

30+ YearsExperienceReliable

07 3801 3858

Lifestyle Granny Flats

Brisbane

Known for modern, box-style designs with clever floor plans. Good for narrow blocks in inner-city Brisbane.

ModernFastStylish

07 3367 8222

The Granny Flat Experts

Sunshine Coast

Sunshine Coast locals. They understand the specific council overlays of the Noosa/Maroochy regions.

LocalCoastalPersonal

0423 596 306

Granny Flats WA

Perth Metro

$$$

Perth’s leading custom builder. They excel at tight access sites and matching the granny flat to your main home.

CustomDifficult SitesPremium

08 9329 9888

Summit Granny Flats

Perth / SW

Part of the massive Summit Homes Group. Offers the security of a large builder with advanced steel frame technology.

Major BuilderSteel FrameReliable

08 9312 0145

Dale Alcock

Perth

$$$

The biggest name in WA building. They build high-spec masonry (brick) granny flats that feel like permanent homes.

MasonryQualityReputation

08 9242 9200

Classic Granny Flats

Perth

WA’s most experienced small home builder. They have a dedicated showroom in Joondalup.

ExperiencedShowroomRange

08 9301 2122

Fox Modular

WA Wide

$$$

Stunning architectural modular designs. Built in Gnangara and trucked to site. Very modern aesthetic.

ModularArchitecturalFast

08 6117 5714

Adelaide Granny Flats

Adelaide

$$$

South Australia’s premier custom builder. Known for high-quality brick veneer and rendered finishes.

CustomLocalQuality

08 8352 6661

Hurst Constructions

SA Wide

A family-owned business offering fixed-price contracts. Great personal service for first-time builders.

Family OwnedFixed PricePersonal

0438 064 456

Austral Constructions

Adelaide

They specialise in traditional concrete-slab construction, not transportables. Permanent-look brick work; sale or rental outcome still depends on the lot and market.

Concrete SlabBrickSolid

08 8251 5919

Sarah Homes

SA Wide

Iconic SA brand. Famous for holiday homes and lifestyle shacks. They offer both build and kit options.

LifestyleHolidayKit/Build

08 8301 8888

Kookaburra Homes

Murray Bridge

The experts for regional SA. They build transportable homes perfect for farms and acreage.

RegionalTransportableRural

08 8531 3333

Tasbuilt Homes

Westbury

$$$

Tasmania’s leading modular builder. They build high-end homes in Westbury and deliver statewide.

PremiumModularStatewide

03 6393 1013

Rainbow Building Solutions

Sorell

Specialists in steel frame construction. They offer custom designs and handle the challenging TAS terrain.

Steel FrameCustomLocal

1300 737 910

Cunic Homes

Hobart

$$$

A major Hobart builder offering bespoke architectural designs for small dwellings.

ArchitecturalHobartCustom

03 6231 8181

Prime Design

Launceston / Hobart

While primarily designers, they partner with trusted local builders to deliver the full package.

DesignDraftingPermits

03 6332 3790

How to read this custom builder directory

What is different from a prefab module?

Custom builders usually pour a slab on your lot and run the full CDC or DA path. That can cost more than a trucked module, but it handles sloping, heritage and tight-access sites that factories often refuse.

Who signs off energy and structure?

Your private certifier, against the National Construction Code. The ABCB publishes the NCC; we do not. Ask the builder for the NatHERS assessor name, not a marketing star rating.

How should I use these cards?

Call with overlays, sewer distance and whether you want a rental or family occupancy. The Granny Flat Guide Team lists public builder details; we are not a builder and we do not take a commission on the jobs you book.

Primary sources

Size caps, approval pathways and dollar bands on this page are planning ranges. Check the current official page before you lodge or sign.

See our editorial standards for how we research and update guides.

Avoid the trap

The “Prime Cost” Trap

The single most common way a fixed-price quote turns into a moving target.

Convert PC items to fixed allowances

Beware the Provisional Sum or Prime Cost (PC) item. Builders estimate low allowances for tapware, tiles and cabinetry to make a quote look attractive. If your real choice costs more, you pay the difference plus margin (around 20%). Ask for a detailed inclusions list, and convert PC items to fixed allowances based on real products. That turns a vague quote into a fixed price contract.

Don’t Start Building Without a Budget

Material costs and council fees shifted again in 2026. Avoid budget blowouts with our free granny flat feasibility calculator.

Estimate site costs (excavation, slab, crane)
Compare kit, modular and custom build types
Four-phase breakdown with instant results

Open the free cost calculator

Have a budget? Get free quotes to compare against your estimate.

Compare the alternatives

Weighing Up Another Build Method?

The right path comes down to your budget, timeline and how hands-on you want to be. Compare the other two options.

Prefab & Modular Homes

Factory-built and craned to site for speed and cost certainty.

Explore this option

DIY Kits

The owner-builder route. Save the builder margin on steel or timber kits.