Waterproof Garden Storage Boxes

Why choose a plastic garden storage box?

A resin outdoor storage box does the job of a small shed for the things you use every week. It sits on a patio or by the back door, the lid lifts in one movement and everything is in reach. There is no roof to felt, no timber to treat and no metal to rust.

Every box on this page is made by Keter from moulded polypropylene resin. That brings three real advantages over wood and cheap metal:

• Durable and rot free. It will not rot or rust. Rain runs off the lid and the walls, and the resin does not soak it up.
• UV protection. The colour is stabilised so the brown, anthracite or grey finish does not fade in the sun.
• Almost no maintenance. A wipe with a damp cloth or soapy water is all it needs. No painting, ever.

Plastic outdoor storage is also light. Even the biggest 870 litre box weighs under 26kg in its delivery carton, so one person can move it empty and two can carry it round to the back garden.

Are garden storage boxes really waterproof?

This is the question most shops skip. The walls and the lid of a resin storage box are waterproof: water cannot pass through polypropylene. But the box is not a sealed container. Keter describes these models as weather resistant or water resistant, and that is the honest way to put it.

Two things let a little moisture in:

• Ventilation. Each box has built-in vents so air moves through. That is deliberate: a fully sealed box traps damp air, and cushions then go mouldy from condensation rather than rain.
• The lid edge. The lid overlaps the walls but has no rubber seal, so wind-driven rain or water pooling on a sloped patio can creep in.

In normal UK weather the contents of a weather resistant outdoor storage box stay dry. For a wet winter, a few simple habits keep everything in good condition (see keeping the contents dry below).

Waterproof garden storage boxes compared

Every box listed here, with the sizes from the Shedstore listings. Prices change daily and the grid above always shows the current price, so here we give bands: the Samoa usually sits around £60 to £70, the Rockwood around £180 to £200 and the XXL around £240 to £280.

All three take a padlock (not included) and arrive flat packed. Inside, the Rockwood measures 1.42m x 0.63m and the XXL 1.36m x 0.73m, so check those figures against the longest thing you want to store.

The three storage boxes

Samoa 270L: small patio box

The Samoa is the smallest and cheapest plastic garden storage box here. It is only 45cm high and 45cm deep, so it tucks against a wall, under a window or on a balcony. The rattan-effect resin looks smarter than a plain tub, and handles plus castors let you roll it out of the way. At 270 litres it suits hand tools, kids' toys, a hose and a few chair pads rather than a full set of furniture cushions.

Rockwood 570L: storage and a bench

The Rockwood is a deck box that doubles as garden seating for two. It is 1.55m long and 64cm high, which is a comfortable bench height, and the piston-powered lid lifts with one hand. The 570 litres take the cushions from a four-seat patio set plus some garden tools. The brown wood-effect finish sits well beside timber decking or fencing.

Keter XXL 870L: the largest storage box

If you are looking for large storage boxes for the garden, the Keter XXL storage box is the biggest Shedstore lists. At 86cm high and 870 litres it swallows the cushions from a corner sofa set, a parasol base, long-handled tools and a pressure washer. Gas-assisted pistons hold up the big lid, and finger recesses at each end make it easier to shift when empty. It comes in brown or a dark anthracite grey.

Looking for another outdoor storage box from Keter, such as the Signature, Darwin or Brushwood ranges? Shedstore does not list those, so they are not here, but you can see the full range on Keter's UK storage boxes page.

What size garden storage box do you need?

Lay out what you want to store and measure the longest item first. Litres alone can mislead: a long outdoor storage box with a low lid holds cushions well but not upright tools. As a rough guide:

• Up to 300 litres: hand tools, toys, a hose reel, chair pads for two. The Samoa fits here.
• 500 to 600 litres: cushions for a four-seat dining set, plus a few garden tools. The Rockwood fits here.
• 800 litres and up: cushions from a rattan sofa set, a parasol, long rakes and spades. That is the XXL.

None of these is made to hold a wheelie bin, a lawnmower or a bike. For those, a plastic wheelie bin store, a plastic bike shed or one of our cheap plastic sheds is the better buy.

Keeping the contents dry

A weatherproof box does most of the work. These habits do the rest:

1. Stand it on firm, level ground. Paving, decking or a small slab base. On a slope or soft lawn the lid twists and leaves a gap, and the bottom can sit in a puddle.
2. Put it against a wall or under cover if you can, out of the direct path of wind-driven rain.
3. Only pack dry items. A damp cushion put away in October will smell by spring.
4. Add a sachet of silica gel for long winter storage, as Keter itself suggests, and swap it now and then. Breathable cushion bags help too.
5. Leave the vents clear. Don't pack fabric tight against them; air movement is what stops condensation.

Security and safety

Every lockable storage box here has a padlock fixing on the lid and front, but no padlock in the kit. Buy a weatherproof padlock with a short shackle so it can't be levered. A locked lid is also a safety feature: it keeps garden chemicals, sharp tools and slug pellets away from children, and stops small children climbing inside a large box. RoSPA's home safety advice covers storing garden products out of reach. For alarms and stronger locks, see shed security.

Don't stand on the lid, and only sit on the Rockwood, the one model listed for it.

Storage box or small shed?

A garden storage box wins when space and budget are tight: it fits where a shed won't, it costs far less, and nothing needs a base or planning thought. A shed wins when you need to stand inside, hang tools on the walls or store a mower. Compare the two on our small plastic sheds page, or if you prefer the same low-maintenance resin in a full-size building, see Keter sheds. Our shelving and wall storage page has racks for whichever you choose.

Garden storage box FAQs

What is the best waterproof garden storage box?

For most patios, the Rockwood: 570 litres, an easy-lift lid and a top you can sit on. Pick the Samoa box for a balcony or a tight budget, and the XXL when you need the most space for sofa cushions.

Can you leave a plastic storage box outside all year?

Yes. The resin is UV protected and will not rot, rust or need painting. Stand it on level ground and keep the vents clear through winter.

Will cushions go mouldy in a garden storage box?

Not if they go in dry. Mould comes from damp items and trapped air, not rain. Air them on a sunny day and use a breathable bag or silica gel for winter.

Can you sit on a garden storage box?

Only on models made for it. The Rockwood is listed as seating two adults. The Samoa and XXL listings do not say so, so treat them as storage only.

Do the boxes come with a padlock?

No. All three are padlock ready, but you need to buy your own lock.

How long does assembly take?

Not long. Each one arrives flat packed with the instructions in the box. The supplier says the Samoa takes minutes; allow a little longer for the larger two.

Can I get spare parts?

Yes. Keter sells spare parts online, which keeps an older outdoor storage box going.