Choose the Right Storage Unit Size

With no industry standard for unit sizes, working out how to choose the right storage unit can feel like guesswork even for people who’ve rented storage before. Get it wrong and you’re either paying for empty space or cramming belongings into something too small. This guide walks through measuring what you own, matching it to real unit sizes, and using StorHub’s free size estimator to land on the right unit the first time.

Why getting the size right matters

Choosing the right storage unit isn't just about fitting your belongings; it's about value. A unit that's too big means paying every month for space you're not using. A unit that's too small means cramming items in, risking damage, or needing a second unit later. Getting it right for the first time saves money and hassle.

Step 1: measure what you're storing

Before you can choose the right storage unit, you need an honest inventory of what's going on in it. Walk through each room (or your garage, shed, or office) and list major items: furniture, appliances, boxes, equipment. For furniture, note rough dimensions length, width, height. You don't need to be precise to the centimeter but knowing whether your sofa is 1.8m or 2.4m makes a real difference to which unit size fits.

If you need a tape measure, masking tape to mark out floor space, or boxes to consolidate smaller items before you store them, the StorHub box shop stocks everything you need.

Storage unit sizes explained

Self-storage unit sizes are typically described by floor area in square metres, but what matters is what fits inside. Here's a practical breakdown of common storage unit sizes and what each genuinely holds:

Size	Approx m²	Fits	Best for
XS / Locker	1–2 m²	Boxes, files, small personal items	Students, document archives, seasonal gear
Small	4–5 m²	Studio / 1-bed contents, wardrobe, small sofa	Apartment moves, short-term declutter
Medium	9 m²	Full 2-bed home: beds, sofa, dining table, appliances	Family moves, renovation, downsizing
Large	18 m²	3–4 bed home contents, business inventory	Large household moves, trade storage
XL / Micro-Warehouse	Up to 50 m²	Full home or substantial commercial stock	Businesses, e-commerce, large-scale storage

Self-storage sizes for specific situations

Storage unit dimensions for a studio or 1-bedroom move

A small unit (around 4–5 m²) comfortably holds the contents of a studio or 1-bedroom apartment: bed, small sofa, a few boxes, wardrobe contents. This is the most common size booked for personal storage during a move or short-term decluttering.

Storage space sizes for a family home

A medium unit (around 9 m²) fits a full 2-bedroom home's worth of furniture and boxes beds, a dining table, a sofa, major appliances. For a 3–4-bedroom home, step up to a large unit (around 18 m²), which comfortably holds an entire household during a renovation or move.

Self storage unit sizes for business stock

Businesses storing inventory, equipment, or archived records typically need more than the standard residential range offers. A business storage unit or, for larger stock volumes, a micro warehouse (up to 50 m²) gives the space to operate without committing to a full commercial lease.

Step 2: use the Visual Size Estimator

Once you’ve got a rough inventory, the fastest way to confirm the right unit is StorHub’s Visual Size Estimator. Enter what you’re storing room by room or item by item and it calculates the smallest unit size that comfortably fits everything, so you’re not paying for space you don’t need.

Common mistakes when choosing a storage unit size

Forgetting walking space, you'll need to access items at the back of the unit, so don't plan to fill every cubic centimeter.
Not accounting for boxes, you haven't packed yet loose items to take up more volume once boxed than people expect.
Sizing for today only if you're likely to add more items over the rental period, size up slightly rather than needing a second unit later.
Guessing instead of measuring a five-minute walk through with a tape measure prevents most sizing mistakes.

Frequently asked questions

Q: What size storage unit do I need for a 1-bedroom apartment?

Most 1-bedroom apartments fit comfortably in a small unit (around 4–5 m²), which holds a bed, small sofa, wardrobe contents, and a stack of boxes. If you're storing larger furniture pieces or a full kitchen's worth of items, step up to a medium unit (around 9 m²) for breathing room.

Q: How do I know if a storage unit is too small?

If you're stacking items right up against the door with no walking space, or items are wedged tightly enough that retrieving anything at the back means unpacking the front first; the unit is too small. Use the Visual Size Estimator before booking to avoid this it accounts for the access space you'll actually need.

Q: Is it cheaper to get a smaller unit and pack tightly?

Not usually, once you factor in the real cost of getting it wrong. A unit packed too tightly risks damage to your belongings, makes access difficult, and often means you end up needing a second unit anyway which costs more than booking the right size from the start. Choose the size that fits comfortably with some access space, not the absolute minimum.

Q: Can I change the unit size after booking?

Yes, StorHub's month-to-month terms mean you're not locked into a unit if your needs change. If you find your unit is too small or larger than you need, contact your facility to discuss moving to a different size, subject to availability.

Find the right size, then book online

Still unsure? Try the Visual Size Estimator for an instant recommendation or browse all StorHub locations to see live availability. Check current promotions for the best available rate. Month-to-month, no lock-in, no deposit required.