About 5J Building Group
5J Building Group has been renovating Melbourne homes for more than 20 years. We're a registered domestic builder specialising in renovations, extensions, kitchens, bathrooms and knockdown rebuilds, and we've completed projects right here in Doncaster and across Manningham and the eastern suburbs.
From updating a dated 1970s brick home to extending a family home on one of Doncaster's sloping blocks, we manage the whole job: design, permits, trades and construction. Start with a free on-site quote, built around your budget, with no hidden costs.
Why 5J
Two decades of renovating Melbourne homes means we know which materials suit which rooms, and where projects typically run into trouble.
Registered Domestic Builder (Unlimited), CDB-U 73492. You're dealing with an accountable, licensed builder, not a middleman.
We organise all the contractors and they work for us. They're vetted, professional and respectful of your home.
Every job starts with a free, customised quote built around your budget. What we quote is what you pay for.
Our project managers monitor every stage so your renovation is delivered on schedule and within the agreed budget.
You'll hear from us every week on progress. Change your mind on a finish? Tell us and we'll work it in.
Our services
Whether it's one room or the whole house, we handle design, approvals and construction under one contract.
Full-house renovations that modernise layout, finishes and function, including landscaping, driveways and fencing.
Learn more →Ground-floor and second-storey extensions that add space for a growing family without the cost of moving.
Learn more →Classic, modern and French provincial kitchens designed around how your family actually cooks and gathers.
Learn more →Ensuites, family bathrooms and laundries, from waterproofing and tiling through to final fit-off.
Learn more →Land selection, feasibility, planning, permits and construction for a brand-new home on your block.
Learn more →Self-contained small second dwellings, prefabricated or built on site, for family, guests or rental income.
Learn more →Recent work
A selection of recent 5J renovations in Doncaster and across Melbourne.
Reviews
Real 5-star reviews from 5J Building Group customers on Word of Mouth.
5J BUILDING GROUP delivered exactly what we asked for – a beautiful, stylish home that is ideal for our family. Thank you for being flexible with our changes during the construction, we got what we hoped for. Thank you, Jason and his team, we would highly recommend 5J to our family and friends!!
5J did an outstanding job on our project, they were professional, reliable, thank you!
I had a wonderful experience here. The team was very professional, friendly, and attentive to details. Everything was handled smoothly and efficiently, which made the whole process stress-free. I really appreciate their excellent service and would definitely recommend them to others
highly recommend Jason and his team, professional, punctual, friendly and great value for money.
Rated 5.0 ★ on Word of Mouth. Read all our reviews
About the area
Doncaster sits about 18 km east of the Melbourne CBD in the City of Manningham. It's a hilly suburb, and many homes enjoy long views across the city and ranges. That's a real asset when renovating, but sloping blocks also affect how extensions are designed, how drainage is handled and how much site preparation is needed.
A lot of Doncaster's housing stock is established brick homes from the post-war to 1970s era. They're solidly built but often have closed-off layouts, dated kitchens and bathrooms, and poor insulation, which makes them ideal candidates for a renovation or extension rather than a move.
| Postcode | VIC 3108 |
|---|---|
| Council | City of Manningham |
| Distance to CBD | Approx. 18 km east |
| Area | 8.9 km² |
| Population | 25,020 (2021 Census) |
| Median age | 41 (2021 Census) |
| State electorate | Bulleen |
| Federal division | Menzies |
| Neighbouring suburbs | Templestowe, Templestowe Lower, Bulleen, Doncaster East, Balwyn North, Mont Albert North, Box Hill North, Blackburn North |
We also renovate across nearby suburbs including Balwyn, Kew, Templestowe and Blackburn. See all suburbs we service.
Local planning
Doncaster is in the City of Manningham, so renovations are assessed under the Manningham Planning Scheme and Victoria's building regulations. These are the controls we check most often before designing a Doncaster renovation.
Every Doncaster property sits in a planning zone, and many also have overlays that add extra rules. You can look both up for free on Manningham Council's property map: search your address, then choose Planning Zones and Planning Overlays. We check this for every job before design starts.
Under the standard residential zone rules, extending a single house often doesn't need a planning permit unless the lot is under 300 m² or an overlay applies. Structural work still needs a building permit from a registered building surveyor, which we arrange.
In the Neighbourhood Residential Zone, homes are limited to 9 m and two storeys (11 m and three storeys in the General Residential Zone). On lots of 400 m² or more, part of the block must stay as garden: 25% for 400–500 m², 30% for 500–650 m² and 35% above 650 m². This often shapes how far a rear or side extension can go.
In a Heritage Overlay, Manningham requires a permit to demolish part of the building, build (including a fence), change the outside or paint surfaces that were never painted; like-for-like repairs usually don't need one. Near creeks, a Special Building Overlay or Land Subject to Inundation Overlay can set minimum floor heights so an extension sits above known flood levels.
Planning rules change and every property is different, so treat this as a general guide rather than planning advice. We confirm the controls for your address as part of your free quote.
FAQs
It depends on the work. Most structural renovations and extensions need a building permit, and some also need a planning permit from Manningham City Council, depending on your property's zoning and any overlays. We check your property's requirements early and manage the permit process as part of the job.
Often, yes. Since September 2025, removing or lopping a larger canopy tree on a residential block in Manningham generally needs a planning permit under Victoria's canopy tree rules (Clause 52.37). Dead trees, weed species and routine maintenance pruning are usually exempt. Many Doncaster blocks have established trees, so we check this at the design stage and build any permit into your timeline.
Yes. Sloping blocks are common in Doncaster and we plan for them from the start, including site cut, retaining, drainage and floor levels, so there are no surprises once construction begins.
Every home is different, so we quote each job individually after an on-site visit. As a general guide, many homeowners aim to spend around 5–10% of their property's value on a renovation. Our quotes are free, tailored to your budget and have no hidden costs.
It depends on the scope. A kitchen and two bathrooms typically take 4–8 weeks, larger renovations usually take 2–4 months, and extensions or new builds can take up to 10 months. We give you a clear timeline with your quote.
Yes. We renovate across Manningham and the surrounding eastern suburbs, including Doncaster East, Templestowe, Bulleen, Balwyn and Box Hill. You get the same team, the same trades and the same free on-site quote wherever you are.
Book a free on-site quote. We'll come to you, talk through your plans and give you a renovation plan built around your budget.
