Self Storage Units Sizes in Northern Ireland

What size of Self Storage Unit do I really need?

If you’ve never rented a self-storage unit before, one of the first questions you’ll face is:

“How big should my storage unit be?”

Pick a space too small, and you’re in for a stressful game of box-Tetris. Go too big, and you’ll end up paying for empty air.

At Think Storage in Lisburn, we’ve helped many customers across Northern Ireland find the perfect-sized unit—so you only pay for what you actually need, and your belongings stay safe, organised, and accessible.

Furthermore if you book a unit and then on the day discover you need more or less space, subject to availability we can change your unit rental to suit. 

1. Start with What You’re Storing

Before looking at unit sizes, make a quick list of everything you plan to store. Group items into categories:

• Furniture (beds, wardrobes, sofas)
• Boxes (label by room or category)
• Appliances (fridges, washing machines)
• Business stock or tools

Expert Tip:

Store boxes on pallets or in sturdy plastic crates to keep things neatly off the floor. This makes it easier to clean, organise, and move things around when needed.

2. Know the Common Storage Sizes

Here’s a quick guide to some typical unit sizes and what they can hold:

Unit Size       Space Equivalent.                  Fits

25 sq ft.         Hall cupboard.                         5–8 medium boxes + a small piece of furniture

50 sq ft          Half a garage                          Contents of a 1-bed flat

75 sq ft          ¾ garage                                 Contents of a 2-bed house

100 sq ft        Full garage                              Contents of a 3-bed house

150+ sq ft      Large garage                           4–5 bed house or large business stock

Expert tip:

You can refer to our website sizing page for a quick guide as to what each size unit typically fits in and/or you can use an online tool such as Calumate to work out the best sized unit for you.

3. Don’t Forget Vertical Space

Most storage units are around 8ft tall, which means you can stack boxes and furniture safely to fit more in. Place heavier, sturdier items at the bottom, then stack lighter ones above for stability and easy access.

4. Plan for Easy Access

If you’ll need to pop in regularly (for example, to collect business stock or swap seasonal items), leave a small aisle inside your unit. This way, you can grab what you need without unpacking everything.

5. When in Doubt, Ask a Local Storage Expert

Our team at Think Storage knows Northern Ireland moves inside and out—from narrow driveways to houses with awkward staircases. We’ll help you choose the ideal unit size based on what you’re storing and how often you’ll need access.

Want to see your options in person? We’re always happy to give you a quick tour of our Lisburn facility so you can picture exactly how your belongings will fit and feel confident in your choice.

Still unsure what storage unit size you need?

Get a free size estimate from our friendly Lisburn team today—call us, message us, or drop in for a tour.

Think Storage – Storage Made Simple in Northern Ireland.