A Frankston granny flat build, day by day: what actually happens on your block for 16 to 22 weeks
Straight answer: 16 to 22 weeks of site time for a 50 to 60 m² custom build, or 8 to 12 weeks once a modular unit is craned in. Six to eight of those days are genuinely loud. You will lose water for 2 to 4 hours once and power for 1 to 3 hours once. You stay living in the house the whole time, and you need to clear a 1.5 m working strip around the footprint before day one.
The timeline below is a real Frankston program for a 55 m² one bedroom flat on a Class M site with side access, built on site rather than craned in. Durations are working days. The two columns that matter most to you are the last two: what happens, and what you have to do so it does not stop.
Stage by stage, with real durations
| Stage | How long | What happens | What you need to do |
|---|---|---|---|
| 1. Site set up | 1 to 2 days | Temporary fence, site toilet, bin delivered, protection over the path and the crossover, silt fence to the stormwater pit. | Clear the 1.5 m working strip, unlock the side gate, tell the neighbours it starts. |
| 2. Service location and clearing | 1 to 4 days | Before You Dig plans checked and services physically located, shed or old paving removed, trees and stumps out where the permit allows. | Point out anything you buried yourself: irrigation, a pool line, an old septic, the dog. |
| 3. Excavation and footings | 3 to 5 days | Bobcat strips the site, trenches or piers to the engineer’s design, footing inspection by the building surveyor. | Move cars off the driveway from 7am. This is the dustiest and loudest stage. |
| 4. Under slab plumbing and pre-slab | 2 to 3 days | Sewer and water rough-in set out, vapour barrier and mesh laid, pre-slab inspection. | Nothing, other than keeping kids and pets off the mesh. |
| 5. Slab pour and cure | 1 day, then 5 to 7 days | Trucks arrive from about 7am, or a pump if access is tight. Slab is finished and left to cure. | Keep the driveway completely clear for the day. Do not let anyone walk on it. |
| 6. Frame and trusses | 5 to 10 days | Wall frames stood, roof trusses craned or lifted on, bracing and tie downs fixed. | Expect nail guns and a compressor. This is loud day number two. |
| 7. Roof, windows and lock-up | 5 to 10 days | Roof sheeting or tiles, fascia and gutter, windows and external doors in, building goes weathertight. | Nothing. Progress suddenly looks fast from the kitchen window. |
| 8. Rough-ins and frame inspection | 4 to 6 days | Electrical, plumbing and data rough-in, heat pump and split system pipework, frame inspection signed off. | Confirm power point and light positions on site. Changes are cheap now and expensive later. |
| 9. Insulation and plaster | 6 to 9 days | Wall and ceiling insulation to the energy report, plasterboard, cornice, setting and sanding. | Expect fine white dust in the air on sanding days. Close the windows on that side of the house. |
| 10. Waterproofing and tiling | 5 to 8 days | Shower and wet area membrane, cure time, floor and wall tiling, grout. | Nothing. Ask for a photo of the membrane before it is covered and keep it. |
| 11. Kitchen, joinery and fit-off | 8 to 12 days | Cabinets, benchtops, doors, skirting, tapware, toilet, appliances, switches, lights, hot water unit connected. | Be home for the colour and handle check if you have not already signed one off. |
| 12. Painting | 5 to 8 days | Prep, undercoat and two top coats inside, external paint or finish where the cladding needs it. | Expect a paint smell across the yard for 3 to 4 days. Low odour paints help but do not remove it. |
| 13. External works | 4 to 10 days | Deck or landing, path, stormwater connected to the legal point of discharge, clothesline, letterbox, turf or mulch. | Decide now if you are doing your own landscaping, so we can leave the levels right. |
| 14. Final inspection and handover | 5 to 10 days | Builder defect walk, final inspection, occupancy permit issued, keys, manuals, warranties and as-built energy rating. | Walk the job with us and write every item down. This is the moment your list carries the most weight. |
Working days for a typical on site build in Frankston, Karingal, Seaford or Carrum Downs during a normal autumn or spring. Winter adds roughly one lost day per week. Call (03) 9022 1391 for a program against your own block.
Access, parking, power and water
Access decides the price and the pace more than anything else on the block. A 2.4 m or wider side access lets a bobcat, a mini excavator and a wheeled trailer get to the back yard, and that is a normal build. A 900 mm gate means everything moves by wheelbarrow, which typically adds $4,000 to $12,000 in labour and one to two weeks. If the concrete truck cannot get a chute within about 8 m of the slab, we add a line pump at $1,200 to $2,500 for the pour.
Parking is the thing neighbours actually notice. On a normal weekday we have two to five vehicles, and on frame day or slab day it is more. We park on the street where it is legal, keep your crossover clear and never block a neighbour’s driveway. If your street has permit or timed parking, tell us at the start so we can plan around it instead of collecting tickets on your job.
We run off your power and water and reimburse it as part of the contract, or install a temporary builders supply at $600 to $1,200 if the switchboard cannot carry it. Everything plugs through an RCD protected lead. Expect the water off for 2 to 4 hours the day the plumber cuts into the main, and the power off for 1 to 3 hours the day the switchboard is upgraded or the new circuit is landed. We give at least 48 hours notice for both, and we do not do it on a day you have told us you have meetings.
Noise, dust, smell, pets and kids
EPA Victoria construction noise hours are 7am to 6pm Monday to Friday and 7am to 1pm Saturday, with no work on Sundays or public holidays. We start at 7am and we do not run the noisy plant before 8am out of courtesy to the neighbours, which matters on the tighter blocks around Karingal and Seaford. Of the roughly 80 working days on site, about 6 to 8 are genuinely loud: excavation, the slab pour, frame day and the two plaster sanding days.
Dust comes in three bursts. Excavation dust is coarse and settles in the yard. Concrete cutting dust is fine and we cut wet. Plaster sanding dust is the one that gets into the house, so keep the windows on that side shut for those two days and bring the washing in. Smell is limited to paint, adhesive and membrane, roughly a week in total, worst for the first 48 hours after painting.
For pets, the honest risk is not the noise, it is the gate. Trades open gates all day. If you have a dog that bolts, we will put a self closing latch or a temporary mesh fence on the access path, and we would rather you ask for it on day one than after the dog is on Cranbourne Road. Kids are the same story: the site is fenced, but a curious eight year old and a stack of frame timber are a bad combination on a Saturday afternoon.
Working from home is entirely doable. Most of our Frankston clients do it. Book calls between 10am and 3pm on the loud days and we will tell you which ones those are the week before.
Want the program for your own block before you commit?
We walk the access, measure the gate, check the services and give you a week by week schedule with the loud days marked.
Prepare for the crew: tick these off before day one
Print this, work through it in the fortnight before your start date, and the first week of your build will run without a single phone call. Your ticks are saved in this browser.
Two weeks before the start date
The week before the crew arrives
Access, power and water
Pets, kids and working from home
Red flags during the build
Weather, waste and what a clean site looks like
Frankston weather costs time in two ways. Rain stops the excavation, the pour and the roof, and it does not stop the plaster, the tiling or the painting. Through July and August, budget roughly one lost day a week and do not let anyone promise you otherwise. The bigger risk is a wet trench: a footing dug on a Friday and rained into over the weekend has to be pumped and cleaned before the inspection, which turns one lost day into three. That is why we try to sequence excavation, footing inspection and pour inside the same week, and why a February to April start is the easiest run of the year. There is more on seasonal timing on the best time to build on the Peninsula.
Waste is a 4 to 6 cubic metre builders bin, swapped three to six times across the build at $450 to $700 a swap, and that sits inside the contract rather than arriving as a surprise. Concrete, brick, metal and clean timber are separated and go to the regional recovery centre at Skye rather than to landfill. One genuine local caution: a lot of Frankston, Seaford and Carrum Downs housing stock dates from the 1950s to the 1980s, so if we are removing an old shed, eaves or fibro wall, we assume asbestos until a sample says otherwise. Non-friable asbestos removal above 10 m² must be done by a licensed removalist in Victoria, and that runs $80 to $150 per m² plus disposal. It is a real cost, and any quote that does not mention it on a pre-1990 house has not thought about it.
A clean site at the end means the bin and the toilet gone, the temporary fence gone, spoil carted away rather than spread over the lawn, the working strip raked back to level, the path and the crossover washed down, the gutters and downpipes clear, and a broom clean interior with the labels off the windows. If you are doing your own landscaping, say so early and we will finish the levels 100 mm low so your turf or mulch sits flush instead of against the cladding.
What we do not do, and what stalls a job
Being straight about the limits: we do not do full landscape design or paving beyond the working strip and the connecting path, we do not do pool works, and we do not carry out demolition of the main house. We also will not start on site before the building permit is issued, even if you would rather we did, because unpermitted work becomes your problem at sale or insurance time. Our page on Victorian permit rules explains why.
In practice, four things stall builds. Rain, which we plan for. A service that is not where the plan said it was, which is common on older Frankston blocks where the sewer was laid before the shed went up. A late change of mind from the owner, which is why we push hard for decisions at rough-in stage. And waiting on an inspection, which is why the surveyor’s footing, pre-slab, frame and final inspections are booked days ahead rather than on the morning. If you want to see how those stages connect to the paperwork side, read the Frankston build process, use our hiring checklist before you sign anything, and check where the site money goes on Frankston site costs. If you are still deciding on size, size it first, and if the budget is the sticking point, start with the three budget tiers.
What homeowners ask us before the crew turns up
How long does a granny flat take to build in Frankston?
How noisy is it and what hours will the crew work?
Do I have to move out, or can I keep working from home?
What do I need to move before the crew arrives?
Where does the waste go and who cleans up?
What actually stalls a granny flat build in Frankston?
Get a week by week program for your block
Send us the suburb and the access width and we will come back within one business day with a start window, a stage program and a fixed price.
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