8x6 Shed Bases

Which shed base kit fits an 8x6 shed?

A shed's name is rarely its exact size, as most are a few centimetres over or under 8ft by 6ft. Take the external floor size in metres from the shed's listing, then pick a platform that's the same size or a little bigger. A ProBASE square is 500 x 500mm and 40mm deep, so a finished platform always grows in steps of half a metre.

That makes the sum simple. Most sheds this size need a platform 5 squares long and 4 squares wide, which is 2.5 x 2.0m and 20 squares. Shedstore sells these in 15, 18 and 25-square kits, so the 25-square 8x7 kit is the one to buy. Lay 20 of the squares under the shed and keep the other 5 as a spare row or a dry step outside the door.

The squares clip together on every side, so you aren't stuck with the shape the kit's name suggests. The maker publishes layout ideas for different footprints on the ProBASE website.

8x6 shed bases compared

Here are the three kits on this page. Platform is the real size of the finished base laid as a rectangle, and gravel is the total at the 15kg per square the maker advises. Prices change every day and the grid above always shows Shedstore's current price, so here they're in bands.

Every kit is the same system, just with a different number of squares. Here's what you get in each one.

• Interlocking squares of high quality recycled plastic, each 500 x 500 x 40mm. They're lightweight enough to carry round the side of the house, yet strong and durable once filled.
• A weed membrane, heavy-duty and commercial grade, to go under the squares.
• Instructions, with customer service support if you get stuck.
• A 2 year guarantee from the maker.

Gravel isn't in the box. The listing recommends 10mm pea gravel, so book a delivery from a builders' merchant for the same week the kit arrives.

The 8x5 and 10x4 packs are both only 1.5m deep, which is too shallow for a 6ft deep shed. They suit a 7x5 shed, a narrow pent shed against a fence, a log store or a bike store.

Our sheds and the base each one needs

These are the real footprints of the sheds this size we list, with the grid layout that covers each one. Every one of them fits on a single 8x7 kit.

The Keter Factor is the one to watch. At 2.57m it's a few centimetres wider than the 2.5m a 5-square row gives, so lay the squares 6 long and 4 wide instead. That takes 24 of the 25 squares and leaves about 20cm of gravel at each end. Keter's own listing for the Darwin asks for a foundation of at least 1.93 x 2.44m, and the 2.5 x 2.0m layout clears it. More sizes are on our Keter Factor sheds and Palram sheds pages.

8x7, 8x8 and 7x5 shed bases

The same packs cover the sizes either side of this one.

• 8x7 shed base. An 8x7 shed is about 2.4 x 2.1m, so it needs the full 5 x 5 layout of the 8x7 kit, 2.5 x 2.5m.
• 8x8 shed base. The same 2.5 x 2.5m square works if the shed is no more than 2.5m on each side. Check the external size before you buy, as some 8x8 models are wider. See our 8x8 plastic sheds for the real sizes.
• 7x5 shed base. The 8x5 kit builds 2.5 x 1.5m, which suits a 7x5 shed up to 1.5m deep. If yours is deeper, use the 8x7 kit laid 5 x 4 instead.
• Smaller or larger. For 6x4 and 5x4 sheds go to our 6x4 shed bases. From 10x8 upwards, our 10x8 and large shed base kits have up to 120 squares.

How to lay a plastic grid shed base

A grid base this size is a morning's work for two people. The ground prep takes longest. The squares are quick and easy to put together, so it's simple to assemble and install the base itself, with no concrete to mix and no special tools.

1. Mark out before laying anything: an area a little bigger than the platform with pegs and string. For a 2.5 x 2.0m base, mark about 2.7 x 2.2m.
2. Strip the turf and any soft topsoil, then rake the soil flat.
3. Compact it firmly. On soft soil or clay, tamp down a thin layer of hardcore or sharp sand first so the grids can't settle.
4. Check it's level with a spirit level on a long straight board, both ways.
5. Roll out the membrane to stop weeds growing up through the base. Overlap any joins in the membrane before laying the squares.
6. Clip the squares together on top, working out from one corner. Laying them takes minutes once the ground is ready.
7. Fill every cell with gravel, brush it flat and check the level again.

For a 20-square layout that's about 300kg of gravel, or 360kg for the 24-square Keter Factor layout. One bulk bag from a builders' merchant is usually enough, with some left to make a gravel strip around the walls. That strip works as a simple french drain, so rain doesn't splash mud up the panels.

Shedstore doesn't install these kits, so it's a DIY job, but a simple one. If you've booked its team to build the shed, the base has to be finished before they arrive.

Why a plastic shed needs a level base

Plastic and resin sheds are fussier than timber ones. Their wall panels slot into the floor, so if the base dips at one corner the frame twists, the doors stop meeting and panels can pop out of their channels. Many plastic sheds come with a floor, but even a built-in floor needs a firm, flat surface under it. Our plastic sheds with floors page shows which models have one.

A gravel-filled base also keeps the shed floor dry. Water drains straight through the open squares, so the shed floor never sits on wet soil. That's what rots a timber floor and leaves damp inside. Light plastic sheds should be fixed down too. Our shed security range has ground anchors and locks.

Other ways to build a base for an 8x6 shed

A plastic kit isn't the only choice. Here's how the usual options compare for a shed this size.

• Concrete slab. The strongest and most permanent. For 2.5 x 2.0m at 100mm thick you'd need about 0.5 cubic metres of concrete on a layer of compacted hardcore, with formwork and a few days to cure. It's a lot of work for a storage shed, and hard to remove later.
• Paving slabs. 600 x 600mm slabs fit this size neatly, as 4 by 3 slabs make 2.4 x 1.8m. Each one has to be bedded on sand and levelled on its own, and a rocking slab shows up in the floor.
• Pressure treated timber frame. Ready-made timber bases in this size are cheap and quick, but wood on wet soil rots in the end, often before the shed does.
• Adjustable base. On a slope or an old sunken patio, a steel bracket system levels the shed without digging. QuickJACK Kit 2 covers sheds from 8x3 to 8x6. See our adjustable shed bases.

Why pick a plastic grid over slabs or concrete?

• Quick to install. There are no slabs or concrete to lay, and no waiting for anything to set.
• Easy to put together. The squares push together by hand, so anyone can assemble the base.
• Strong and durable. Once filled with gravel, the base is firm enough for a shed full of tools and bikes.
• Lightweight to handle. Each square weighs very little, so delivery and carrying are easy, even through a house.
• Made from recycled plastic. It won't rot in wet soil the way timber does.
• Suitable for more than sheds. The same kits work under a log store, bike store or small summerhouse.

For a flat lawn, a kit filled with gravel is usually the cheapest and easiest of these. You can also lift it and lay it again if you ever move the shed.

Do you need planning permission for an 8x6 shed?

Usually not in England. A shed counts as permitted development if it stays behind the front of the house, is single storey, and covers no more than half the garden. Within 2m of a boundary it must be no more than 2.5m tall, so check the height on the shed's listing. The Planning Portal guide to outbuildings has the details, and the government's permitted development technical guidance explains how height is measured. A 40mm grid base adds almost nothing to that height. Listed buildings, flats and conservation areas have extra rules, and Wales, Scotland and Northern Ireland set their own.

8x6 shed base FAQs

Is there a ProBASE kit made for an 8x6 shed?

ProBASE does make a 20-square pack for this size, but Shedstore sells the 25-square 8x7 kit instead. Lay 20 squares as a 2.5 x 2.0m rectangle and you have the same base, plus 5 spares.

How much gravel do I need for an 8x6 shed base?

About 300kg of 10mm pea gravel for 20 squares, at the 15kg per square ProBASE recommends. Allow more if you want a gravel strip around the shed.

Do I have to fill the grids with gravel?

Yes, for these kits. Shedstore's listing for every pack recommends 15kg of 10mm pea gravel per square. The gravel adds weight and strength and locks the squares in place.

Can I lay a shed base on grass?

Not straight onto turf. Strip the grass and soft topsoil, compact the ground and check it's level, then lay the membrane and grids.

Does the base need to be bigger than the shed?

It should be at least as big as the shed's outside footprint, and a little bigger is better. A margin of gravel keeps the walls clear of soil and grass.

What guarantee do the kits have?

Each kit has a 2 year guarantee from the maker, and comes with instructions and customer service support. The recycled plastic won't rot, so a base laid on well-drained ground should outlast that by a long way.

Can I move the base later?

Yes. Nothing is glued or cast in place, so you can rake out the gravel, unclip the squares and lay them again somewhere else.