Frankston’s specialist granny flat & second-dwelling builders.
1-bedroom, 2-bedroom, dual-occupancy and NDIS SDA second dwellings across Frankston City and the Mornington Peninsula. VicSmart fast-track where eligible, full planning permit where required. VBA-registered builder, NCC 2022 / 7-star NatHERS compliant. Free design consultation and fixed quote in 7 days.
Five granny flat & second-dwelling formats.
Every block, every family, every budget is different. We design and build five distinct second-dwelling formats — from sub-25m² garden studios with no council permit needed, through to full NDIS SDA-compliant homes worth $500K+ on completion.
1-Bedroom granny flats
35–50m². The classic ageing-in-place or adult-child solution. Open-plan kitchen/living, one bedroom, bathroom. $90K–$180K depending on modular vs custom and Peninsula coastal-finish requirements.
See 1-bedroom →2-Bedroom granny flats
60–90m². For couples, parents with a teen, or long-term rental. Two bedrooms, one bathroom, full kitchen, living, often a small study nook. $140K–$220K.
See 2-bedroom →Dual-occupancy second dwellings
90–130m². Full second dwelling designed to be subdivision-ready (separate title in future). Independent services, entry, parking. $180K–$280K. Best for Frankston South / Mt Eliza larger blocks.
See dual-occupancy →Garden studios & home offices
12–25m². Below the 25m² / 3.6m height threshold = no planning permit needed in most zones. Home office, teen retreat, hobby workshop. $25K–$95K depending on plumbing.
See garden studios →NDIS SDA granny flats
Specialist Disability Accommodation, SDA-compliant to NDIA Design Standard. Improved Liveability through High Physical Support categories. $300K–$600K. Eligible for SDA rental income through registered SDA provider.
See NDIS SDA →Three things every Frankston & Peninsula granny flat needs to get right.
The right council pathway.
Frankston City Council and Mornington Peninsula Shire have very different planning frameworks. Frankston City allows one second dwelling per lot ≥300m² with VicSmart fast-track (10 business days) for builds under 60m² that meet ResCode. The Peninsula Shire has overlays — DDO (Design and Development), HO (Heritage), ESO (Environmental Significance), BMO (Bushfire Management) — that can each require a separate permit condition. We’ve lodged in both councils for years and know the shortcuts.
The right thermal design (NCC 2022 / 7-star NatHERS).
Every new dwelling in Victoria from 1 May 2023 must achieve a 7-star NatHERS energy rating. For small granny flats this is harder, not easier — less thermal mass and higher surface-area-to-volume ratio means insulation, glazing and orientation have to be spot-on. We design with a NatHERS assessor from day one rather than discovering at permit stage that the window/wall ratio is wrong.
The right siting on Peninsula coastal blocks.
Mt Eliza, Mornington, Mt Martha and the southern Peninsula sit in AS 4312 salt-spray zones. Specifying stainless fixings, hot-dip-galvanised structural steel, marine-grade cladding sealants and elevated subfloor ventilation adds 4–8% to build cost but doubles the structural life. We do this as standard within 3km of Port Phillip or Western Port Bay.
Where we build.
We service the full Frankston City and Mornington Peninsula Shire municipalities. Coastal-zone homes within 3km of the bay get salt-spray-rated specifications as standard — not as an upsell.
From enquiry to keys — 5 stages.
Free consultation
On-site visit. Site survey, soil check, services audit, council zone check. 60 min, no obligation.
Design & fixed quote
Concept drawings, NatHERS pre-assessment, fixed-price quote within 7 days of consultation.
Permits
VicSmart (10 days) or full planning permit (3 months). We lodge with council on your behalf.
Build
Modular (12–18 weeks) or custom on-site (20–30 weeks) from contract. Weekly progress updates.
Handover & warranty
Final inspection, council occupancy permit, NatHERS as-built rating. 6-year structural warranty + 12-month defects warranty.
Frankston & Peninsula granny flat FAQs.
How much does a granny flat cost in Frankston?
Most builds fall between $90K and $280K. 1-bed modular $90K–$130K, 1-bed custom $130K–$180K, 2-bed $140K–$220K, dual-occupancy $180K–$280K. Garden studios $25K–$95K. NDIS SDA-compliant $300K–$600K. Site prep, council fees, NatHERS report and connections add $8K–$25K.
Do I need a planning permit?
Frankston City: lots ≥300m² can have one second dwelling. Under 60m² uses VicSmart fast-track (10 business days). Over 60m² or in an overlay: full planning permit (3 months). Mornington Peninsula Shire has tighter DDO/HO/BMO controls. We lodge both.
How long does a build take?
Modular 12–18 weeks. Custom on-site 20–30 weeks. VicSmart can shave 6–10 weeks off approval time. Site prep is 2–3 weeks regardless of method. We sequence approval and design in parallel.
Can I rent it out (long-term or Airbnb)?
Long-term rental: yes in most cases. Short-stay/Airbnb: Mornington Peninsula Shire requires registration with precinct caps; Frankston City is lighter. We design with future rental in mind — separate entry, separate meters, sound separation — so you keep options open.
Ready for a free on-site design consultation?
60 minutes. We measure, check soil, check zone, give you the honest answer on what’s possible.