Large Plastic Sheds

What counts as a big plastic shed?

There is no fixed definition, but most UK retailers treat anything bigger than 10x8 as large. On this page every shed has a floor area of 90 square feet or more, which is roughly 8.4 square metres. That takes in the popular 8x12 (the same shed people search for as a 12x8 plastic shed), the 10x11'5 that sits closest to a 10x10 or 10x12 plastic shed, and long or wide models up to 11 x 21 feet.

Feet are rounded, so always check the metric figure. The Keter Newton Plus is sold as a 7'5 wide model but measures 2.30m including the roof overhang and 2.10m at the base. The Palram Canopia Yukon 11x13 is 3.32m x 3.93m. Measure your plot, then allow at least 60cm around the shed to build it and to reach the panels later.

Benefits of a large plastic garden shed

A big shed is a long-term buy, and plastic has some clear advantages over a wooden or metal shed at this size:

• Low maintenance: no painting, wood treatment or roof felt, ever. A hose down once a year keeps the panels clean.
• Weather resistant: polycarbonate and resin will not rot, rust or swell in wet weather, and the panels are UV protected so the grey does not fade in the sun.
• Light inside: every roof here lets daylight in, so the outdoor storage space is bright without a cable.
• Long warranties: 10 to 15 years, far longer than most wooden garden sheds come with.
• Easy to move: the panels unbolt, so you can take a plastic storage shed with you if you move house.

Large plastic sheds compared

Here is every outdoor storage shed on this page, with the measurements and price bands from the Shedstore listings. Mirror-image versions (13x7'5 and 7'5x13, for example) share a row because the floor plan is the same; only the door position and roof direction change. Prices move, so they are shown as rough bands; the grid above has today's price.

Floor areas include the roof overhang where Shedstore gives it. Every model is grey: dark grey for the Rubicon and Yukon, and a wood-textured grey for the Keter plastic sheds.

The four ranges of plastic garden shed

All 20 sheds come from four ranges. They differ more in materials, shape and floor than in price.

Rubicon: long, narrow and the lowest price

The dark grey Rubicon is 2.37m wide and comes in four lengths, from 3.77m to 6.03m. The walls are 10mm multi-wall polycarbonate on a rust-resistant aluminium frame, the shingle-style skylight roof lets soft daylight in while staying opaque from outside, and an anti-slip polycarbonate floor and anchor kit are in the box. It is tested to 115km/h winds and an 80kg/m² snow load. The ridge is 2.35m, the lowest here, which matters if the shed will stand next to a fence (see planning below).

Yukon: the widest and tallest, with or without a floor

The dark grey Yukon is the heavy-duty option: 3.32m wide, 10mm commercial-grade walls, a 0.9mm shingled skylight roof with built-in guttering, and the widest Palram doors at around 1.47m. Each size is sold two ways. The cheaper version stands on a galvanised steel perimeter base with no floor, so you lay it on concrete or slabs and that becomes the floor. The dearer one adds a waterproof, slip-resistant wood polymer composite (WPC) floor. Snow load ratings on the listings run from 75 to 100kg/m² and wind resistance is 100km/h. More of the range is on our Palram Canopia sheds page.

Keter Newton Plus: wood-look resin for long or wide plots

The Newton Plus is the Keter large shed most people mean. Its grey double-wall Evotech resin panels have a wood texture and steel reinforcement, the heavy-duty floor is included, and there are two Victorian-style windows, a full-length skylight and built-in ventilation. The layout is modular: you choose where the doors and windows go as you build. The 7'5 x 13, 15 and 17 versions have the door in the gable end, and the 13, 15 and 17 x 7'5 versions use a reverse apex roof with the doors on the long side. See every size on our Keter Newton Plus sheds page.

Keter Stronghold: the strongest roof and best locks

The Stronghold is the toughest shed on the page. Its apex roof is steel-reinforced and rated to a 150kg per square metre snow load, the double doors have a 3-point locking system and a one-handed handle, and the 1.525m doorway is the widest here. It comes in 10 x 11'5 and 10 x 15, each with a heavy-duty floor, a skylight and transom windows. The warranty is 10 years, shorter than the others. Compare it with the rest of our heavy duty plastic sheds or see the Keter Stronghold sheds on their own.

Which size of plastic garden shed do you need?

Start with the largest thing you need garden storage for, then check the doorway and the shape of the plot, not just the floor area.

• A ride-on mower or garden tractor: measure its widest point, deck included. The Stronghold (1.525m) and the Yukon (about 1.47m) have the widest double doors, and both Yukon versions have a low threshold ramp.
• Several bikes plus tools: a Rubicon 8x12 or 8x15 gives storage for bikes along one wall with shelving on the other. For bikes only, our plastic bike sheds are cheaper.
• A workshop or hobby space: the Yukon 11x13 or a Stronghold gives a 3m-plus width, so a bench along the back wall still leaves room to move. Every roof lets light in, so you rarely need a lamp in the day; for evenings, see solar shed lighting.
• A long, narrow garden or side return: the Rubicon (2.37m wide) or a narrow Newton Plus at 2.30m wide.
• A wide but shallow plot along a back fence: the Newton Plus 15 x 7'5 or 17 x 7'5, with the doors on the long side so everything is within reach.

Plan your shelving before you choose. Wall racks and freestanding units take 30 to 45cm off each side; our shed shelving and wall storage page has options that suit plastic walls.

How much do large plastic sheds cost?

Expect to pay a price of about £1,250 to £3,300 at Shedstore, and check the price in the grid above, as it changes often. Roughly, by range:

• Rubicon: around £1,250 for the 8x12 up to £1,850 for the 8x20, floor included. The best price per square metre on the page.
• Yukon without a floor: around £1,250 to £2,850, depending on length.
• Yukon with a WPC floor: around £1,750 to £3,300.
• Newton Plus: around £1,900 to £2,450.
• Stronghold: around £1,950 to £2,500.

On top of the shed price and any delivery charge, budget for a base: a large grid kit or concrete slab adds a few hundred pounds, and a good padlock or alarm a little more. For a lower price, see our cheap plastic sheds.

Large plastic sheds with a floor

Sixteen of the twenty sheds here include a floor: polycarbonate on the Rubicon, WPC on the Yukon floor versions and a heavy-duty resin floor on both Keter ranges. The four Yukon sheds without a floor are cheaper by roughly £330 to £650 and suit a garage-style concrete base, where you may want to drive or wheel heavy kit straight in. If a floor is a must, our plastic sheds with floors page lists every size.

A floor still needs a firm, level base under it. Concrete or paving slabs work for every model. ProBASE plastic grid kits on our large shed bases page go up to 5 x 6m, which covers everything here except the 6.03m Rubicon 8x20 and the 6.43m Yukon 11x21; those need a slab or concrete base. On uneven ground, an adjustable shed base can level the frame without digging.

Plastic vs metal and wooden sheds

At this size, the big advantage of a plastic storage shed is low maintenance. Polycarbonate and resin do not rot, rust or need treating, and the panels keep their grey colour. A large wooden garden shed needs a coat of treatment every year or two and new roof felt every few years. Metal sheds are cheaper for the floor space but can dent, and bare steel walls drip with condensation on cold mornings. Wood is easier to fix shelves to and to customise. As garden storage for mowers, bikes and tools that you want to forget about, plastic is the easy choice. For a fuller comparison, read plastic vs wooden sheds.

Planning permission and building regulations for a large shed

In England, a garden shed is normally permitted development if it is single storey, not in front of the house, and outbuildings cover no more than half the garden. The key rule for big sheds is height: within 2m of a boundary, the shed can be no more than 2.5m high. The Rubicon (2.35m) and Newton Plus (2.46m) are under that. The Yukon (2.52m) and Stronghold (2.51m) are just over, so stand them more than 2m from the fence, or check with your council. Height is measured from the ground, so a raised base adds to it. The Planning Portal outbuildings guide has the full rules, and listed buildings, conservation areas and National Parks have tighter limits.

Building regulations rarely apply to a shed under 15 square metres. Between 15 and 30 square metres, you will not normally need approval if there is no sleeping accommodation and the shed is at least one metre from any boundary. That affects the Yukon 11x17 (17.2 m²) and 11x21 (21.3 m²). See the Planning Portal's page on building regulations for outbuildings. In Scotland, check mygov.scot.

Delivery: what to expect

These sheds arrive flat-packed and are heavy: packaged weights run from about 99kg for the Rubicon 8x12 to 384kg for the Yukon 11x21 with its WPC floor. Shedstore gives the delivery details and charges for each one on its product page, so check them before you order, and clear a dry, flat space near the gate or drive for the boxes. Have the base built and set before delivery day, and keep the garden path clear.

Assembly and anchoring

Plan on two people for the build. The Rubicon and Yukon panels slide into the frame; a calm, dry day helps with the big roof sections. Anchor the shed to the base, especially on an exposed outdoor plot. The Rubicon includes an anchor kit (a Hilti screw kit on the 8x17), and Canopia and Keter list the fixings for each model.

Shed security and locks

A shed full of mowers, bikes and garden storage is worth protecting. The Stronghold has 3-point locking; the Newton Plus has a locking lever, the Yukon lockable double doors and the Rubicon a latch with a sliding bolt. None includes a padlock, so add a closed-shackle one. The roof panels are opaque from outside, so nobody can see what is stored in there. For alarms, ground anchors and locks, see shed security.

Large plastic sheds FAQs

What is the biggest shed you can buy here?

The Yukon 11 x 21.3, at 3.32m x 6.43m, gives about 21 square metres of floor. It comes with or without a WPC floor.

Is there a 12x8 or 10x10 plastic shed?

The Rubicon 8x12 is the 12x8 size, with a floor included. There is no exact 10x10 at the moment; the Keter Stronghold 10 x 11'5 is the closest, and the 8x8 plastic sheds are the next square size down.

Which big plastic shed has a floor?

All the Rubicon, Newton Plus and Stronghold sheds, plus the Yukon versions with a WPC floor in the name.

Are plastic garden sheds strong enough for snow?

Yes. The Stronghold roof is rated to 150kg/m² of snow, the Yukon to 75 to 100kg/m² and the Rubicon to 80kg/m², with wind ratings of 100 to 115km/h on the Palram sheds. Anchor the shed to its base on an exposed outdoor plot.

Do plastic storage sheds get condensation?

Any closed shed can on cold mornings. The Newton Plus and Stronghold have built-in ventilation; with the others, open the doors on dry days and keep the base above wet ground.

How long do plastic storage sheds last?

The warranties are a fair guide: 15 years on the Yukon and Newton Plus, 12 on the Rubicon and 10 on the Stronghold. The panels do not rot or rust.