Does a shed add value before you sell?
Sometimes. It depends almost entirely on whether the house is under-garaged for its street, whether the shed has a permit, and whether you have the three to four months a proper build actually takes. Here is what we tell Casey sellers who ring us with the auction date already booked.
Under-garaged blocks gain. Everything else is a coin toss.
The City of Casey is two housing markets stacked on top of each other. The older stock, meaning the 1980s and 1990s streets in Narre Warren, Hampton Park, Endeavour Hills and central Cranbourne, was built with single garages, carports or tandem drives. Buyers walking those houses in 2026 own two cars, a boat or a caravan, and a garage full of tools. A lock-up shed on those blocks is filling a gap the buyer can feel the moment they walk down the side.
The newer stock, meaning Berwick Waters, Clyde North, Cranbourne East and the Narre Warren South estates built since about 2005, already has a double garage under the main roof and a 400 to 550 square metre block with barely any yard left. Put a shed on that and you have not added storage, you have deleted the lawn. Agents in those estates will tell you the same thing.
Worked example: 9m x 6m workshop, Narre Warren South (2026 pricing).
A 1990s four-bedroom on 680 square metres with a single garage. Class M reactive clay, gentle fall to the rear, side gate access. The workshop is sited across the back corner, roof colour matched to the house, one motorised roller door and one personnel door.
- Engineered slab to AS 2870, 54 square metres at $110 per square metre = $5,940
- BlueScope C-section frame and Colorbond cladding, 2.7m wall height = $9,200
- Motorised roller door $1,750, personnel door $620
- Gutters, downpipes, whirlybird and soffit vents = $480
- Electrical rough-in, lights and general power outlets = $1,650
- Casey building permit, private surveyor and AS 1170 engineering certificate = $1,350
- Erection labour and site clean = $3,100
Total: $24,090. Agent appraisals on that street put the uplift at $15,000 to $28,000. So the honest range is somewhere between losing $9,000 and making $4,000, and where you land inside that band comes down to three things: the permit, the siting, and whether the buyer pool for that street actually wants a workshop. On the rural-residential blocks in Berwick south of the freeway the same shed does better, because machinery storage is what those buyers are shopping for.
Note what that example does not include: a mezzanine at $220 to $420 per square metre, insulation at $28 to $48 per square metre, or three-phase power. Those are things you build for yourself, not for a buyer. Nobody has ever paid a premium for somebody else’s mezzanine. The full breakdown of every line item is on our pricing guide.
The permit is the whole ball game.
This is where pre-sale shed money is actually won or lost. Section 32 of the Sale of Land Act 1962 requires the vendor statement to disclose particulars of any building permit issued for the property in the preceding seven years, plus any building notice or building order. A permitted shed is a positive disclosure: here is the permit, here is the AS 1170 engineering certificate, here is the certificate of final inspection. That documentation converts a shed from a question mark into an asset the valuer will count.
An unapproved shed is the opposite. The purchaser’s conveyancer finds it, the lender’s valuer excludes it, and you spend the last week before settlement negotiating against yourself. Retrospective approval is possible but slow, and it is not a job you want to start during a campaign. Sort it first. Our Casey permit guide walks through the thresholds and the overlays that catch people out.
Timing: three to four months, not three weeks.
Sellers consistently underestimate this. A City of Casey building permit runs four to eight weeks from lodgement. Steel lead time is another four to eight weeks and the two only partly overlap. The slab needs seven to fourteen days of cure before the frame goes up, full design strength at 28 days. Erection is two to ten days depending on size. Then the final inspection and the certificate. Realistically you want to start four months before the sign goes in the ground. If you are already at the styling stage, the money is better spent elsewhere, and we will tell you that on the phone rather than take the job.
If it is an investment property.
The calculation is different again, because you are weighing rent and depreciation rather than a one-off sale price. We run those numbers on the rental property shed page. For the standard specifications and inclusions on a residential garage, see garages and workshops.
Pre-sale shed questions.
Does a shed add value to a house in Narre Warren?
A permitted, well-sited shed on a block with room to spare usually returns somewhere between 60% and 110% of what it cost, and the return is best where the house is under-garaged for its street. A Narre Warren South four-bedroom with a single garage and a 650 square metre block gains real money from a double garage or workshop. The same shed on an already double-garaged Berwick Waters house with no back yard left over subtracts value, because you have traded the only usable outdoor space for storage the buyer already has.
Do I have to disclose the shed when I sell?
Yes. The vendor statement under section 32 of the Sale of Land Act 1962 must disclose particulars of any building permit issued for the property in the preceding seven years, along with any building notice or building order. If your shed has a permit, that disclosure is a positive: it proves the structure is legal and engineered. If it does not, you are disclosing an unapproved structure, or worse, failing to disclose one. Purchasers in Casey and their conveyancers check this routinely now, and it is a standard price-chipping lever a week out from settlement.
Is it worth building a shed just before selling?
Rarely, on timing alone. A City of Casey building permit takes four to eight weeks, steel lead time runs four to eight weeks, the slab needs seven to fourteen days to cure before steel goes up, and then you want the certificate of final inspection in hand. That is a three to four month runway before the sign goes up, and a half-finished shed on the block during the campaign is worse than no shed. If you have that runway and the house is genuinely under-garaged, it stacks up. If you are listing in six weeks, do not start.
What kind of shed gives the best return before sale?
A lock-up double garage or a 6m x 9m workshop in Colorbond, matched to the house roof colour, sited off the back corner so the yard is still a yard. Buyers pay for secure parking and a dry workspace. They do not pay for a mezzanine, three-phase power they will never use, or an oversized industrial-looking structure that dominates a residential block. Over-capitalising on the shed is the most common mistake we see: a $60,000 workshop on a $780,000 Casey house does not get you $840,000.
Will an unapproved shed stop the sale?
It will not usually stop it, but it will cost you. The three things that happen: the purchaser’s conveyancer requires a price reduction or a retrospective permit as a condition of settlement, the lender’s valuer excludes the structure from the valuation so the buyer’s finance gets tighter, and in a bad case the purchaser rescinds on a defective vendor statement. Retrospective approval costs $2,500 to $6,000 and takes six to twelve weeks, which you do not have mid-campaign. Sort it before you list, not during.
Where we build.
Thinking of selling? Get the numbers first.
We will tell you straight whether the shed pays on your block, or whether you are better off keeping the yard.