The question behind the question
People downsizing almost always ask what size unit they need. It is a reasonable question and it is usually the second one, because the first is which belongings are actually going into storage.
Downsizing is different from a normal move. In a normal move everything travels and the only variable is the truck. In a downsize you are moving from more space to less, and storage is frequently being used to delay a decision rather than to bridge a gap. That is a perfectly human thing to do, and it is also the single most expensive mistake in this whole process.
So it is worth working through what belongs in a unit before working out how big the unit should be. Our guide to how removalists support a downsizing journey covers the broader process, and the sorting comes first.
Three categories, not two
Most people sort into keep and discard, then put everything they cannot decide about into storage. Try three categories instead. Things going to the new home. Things going because they have a known future, such as furniture for a child who will need it in two years. And things you are storing because deciding feels hard. The third pile is the one to deal with now.
What actually fits in each size
Units are sold by floor area, with ceilings usually between 2.4 and 3 metres, so the volume available is considerably more than the floor plan suggests if you stack properly.
| Floor area | Roughly equivalent to | Typical downsizing load |
|---|---|---|
| 3 square metres | A small bathroom | Boxes, tools, a few chairs, seasonal items |
| 6 square metres | A single garage bay | One bedroom of furniture plus cartons |
| 9 square metres | A single garage | Two bedrooms, a lounge setting and whitegoods |
| 12 square metres | A large single garage | Most of a three bedroom home |
| 18 square metres | A double garage | A four bedroom home including outdoor furniture |
| Half a shipping container | Around 15 cubic metres | A common container storage option in Perth |
Those are guides rather than guarantees. Packing quality changes the answer by a full size category, and a well packed smaller unit routinely beats a badly packed larger one.
The maths that decides what is worth storing
Here is the calculation almost nobody does before signing a storage agreement, and it takes about two minutes.
Take the monthly rate and multiply it by the number of months you realistically expect to need the space. Perth households have described paying around $130 a month for roughly half a container of storage, so a year at that rate is a little over fifteen hundred dollars. Then ask what it would cost to replace the contents of that container secondhand.
For heirloom furniture, a good dining setting or quality timber pieces, storage wins comfortably. For flat pack wardrobes, a tired sofa and a spare mattress, it usually does not, and Perth residents comparing those numbers have concluded openly that giving things away and rebuying later was the cheaper option.
That is not an argument against storage. It is an argument for storing the right things, and it is why a reputable provider should be willing to talk you out of a larger unit than you need.
“Multiply the monthly rate by the months you will really need it, then compare that to the replacement cost of what is going in. If the storage costs more than the contents, the contents are not what you are paying to keep.”
What belongs in storage and what does not
Some things earn their rent and some things never will.
- Solid timber and antique furniture. Expensive and often impossible to replace.
- Items with a confirmed future. Furniture for a child’s first home in two years.
- Documents and irreplaceable records. Small, light and worth protecting.
- Tools and equipment. Costly to rebuy and compact to store.
- Seasonal and sentimental items. Genuinely worth keeping and small in volume.
Against that, flat pack furniture rarely survives dismantling and reassembly well enough to justify the rent, mattresses are bulky and cheap to replace, and anything already broken will still be broken in a year. Our guide to decluttering sustainably covers how to rehome what you are letting go rather than sending it to landfill.
A few Perth specifics
Worth knowing before you start ringing around.
Perth operators are among the least likely in the country to publish rates, and residents report that supplying contact details leads to persistent follow up calls and messages. Ask for pricing in writing by email, and be clear you are comparing options rather than ready to book.
Ask about rate reviews specifically. Perth customers have described increases arriving within months of moving in and, in some cases, being offered a cheaper rate only by shifting their belongings to a different unit in the same facility. Ask how often rates are reviewed and how much notice you receive, and get the answer in writing.
Finally, ask whether insurance is compulsory and whether you may use your own. It is commonly a condition of the agreement and it is almost never included in the quoted rate.
Preparing furniture so it survives the wait
Storage damage is usually preventable, and it almost always comes from the same handful of causes.
Clean and fully dry everything before it goes in, because moisture trapped in upholstery is how mould starts. Dismantle beds and tables where you can, keeping fittings bagged and taped to the frame. Wrap timber in breathable covers rather than plastic, which traps condensation. Defrost fridges and freezers thoroughly and store them with the door ajar. Stand mattresses on their long edge and keep them off the floor.
Our guide to protecting furniture during removals covers the preparation in detail, and the same principles apply to a year in a warehouse as to a day in a truck.
Settle cover before anything goes in. Consumer guidance recommends storage insurance against events such as fire and water damage whenever goods are stored for any length of time, and if a removalist is handling the move as well, transit cover can usually be extended across the storage period for a separate premium. For market context, the Self Storage Association of Australasia reports average occupancy of 85 per cent by area and an average fee of $394 per square metre. Our comparison of storage solutions and our guide to moving to Perth cover the rest.
Key points
- Decide what is going into storage before choosing a unit size.
- Downsizing often uses storage to postpone a decision.
- Sort into three piles rather than two, and deal with the undecided one.
- Give every stored item an end date and a purpose.
- Three square metres suits boxes and a few small items.
- Nine square metres suits two bedrooms plus a lounge and whitegoods.
- Twelve to eighteen square metres covers most three and four bedroom homes.
- Ceiling height is included in the price, so stack to use it.
- Multiply the monthly rate by the real duration before committing.
- Compare that total against the replacement cost of the contents.
- Solid timber, tools, documents and heirlooms usually justify the rent.
- Flat pack furniture and old mattresses usually do not.
- Ask Perth operators for written quotes to avoid persistent follow up.
- Ask how often rates are reviewed and what notice applies.
- Clean and dry everything, and wrap timber in breathable covers.
Downsizing well is mostly a sorting exercise, and the storage unit is simply the tool that holds whatever survives it. Be honest about what has a future, run the replacement cost comparison, and buy the space you need rather than the space that defers the decision. Grace can assess your volume and talk through both self storage and container options before you commit.
