Building a garden shed is the answer to many storage problems in the UK if you live in a tiny modern home and don’t have a garage. But, what is the average cost of building a shed?
Typically, a 6ft (1.8m) x 4ft (1.2m) shed costs about £700 to buy and install, whereas a 12ft (3.6m) x 8ft (2.4m) shed costs around £1150. These amounts are for sheds in the London area, often 20% higher than elsewhere.
These shed assembly prices are estimated and depend on many factors we’ll consider later. However, the most significant factors are size and material. Also, these factors govern the build time too. To erect a small wooden shed, allow up to two days, including the base. In contrast, allow three days for a larger one.
Main Topics
How Much to Build a Shed?*
UK households can use the figures in the table below as a wooden shed building cost estimator.
| Shed size | Materials | Labour | Estimated cost |
|---|---|---|---|
| 6ft (1.8m) x 4ft (1.2m) | £450 | £250 | £700 |
| 6ft(1.8m) x 8ft (2.4m) | £580 | £320 | £900 |
| 12ft (3.6m) x 8ft (2.4m) | £750 | £400 | £1150 |
| 12ft (3.6m) x 12ft (3.6m) | £950 | £550 | £1500 |
*Disclaimer: Prices are just estimates, and you should use them as a starting point for your own research. Contact a local shed fitter or carpenter, or use the form on this page for more accurate rates.
Shed Building Cost Factors
Below we’ve outlined the aspects which will influence your quotation.
Base
Sheds bought from a garden centre or specialist supplier usually come complete with wooden floor and floor joists. However, you need a base on which to rest the floor. You can use a few different base variations here, such as a concrete slab, paving slabs, strip foundations, or whatever foundation type is best in your circumstances.
Whichever base you choose must be built to accommodate the joists prefixed to the wooden floor and extend at least 100mm past the shed walls.
For a typical 4ft x 6ft shed and a poured concrete base, the base materials cost about £80, with labour costing around £250, taking about eight hours. In contrast, the same sized shed with concrete paving slabs costs £75 in materials and £150 for labour and takes five hours.
Size
Size is the most critical factor when choosing your shed. There are several ways of looking at this:
- Make it big enough to do the job, but don’t make it bigger than needed. If it’s a DIY workshop, ensure there’s enough room to lift and store the largest piece of plywood. And, you only need a small shed if it’s to store garden tools.
- How big is it compared to your garden? A shed that’s too big for your garden will be an eyesore, whereas a small hut in a large garden might soon become lost. And, don’t forget, Planning Regulations limit shed size too.
- If you intend it as a general storeroom, buy a shed as large as you can afford. If you don’t, you’ll soon find that you can’t get to the tools or bikes because of the amount of clutter.
Materials
When you think of a garden shed, most people picture a wooden construction with bitumen felt covered roof. But, often, you’ll find an old corrugated iron or concrete shed doing the job. These aren’t used much these days, except for permanent outbuildings. However, garden sheds made from aluminium or plastic have become increasingly popular recently.
Although wooden sheds are great, a metal shed is much more secure and comes in various colours using hot-dipped plastic coatings. However, a metal shed is often more expensive than a wooden one but needs less maintenance over the years.
Finally, plastic sheds are more lightweight than wood and metal, and are often the cheapest of the lot. They’re easier to move around and need no maintenance apart from an occasional wash. However, if they’re not anchored to the ground properly, they might get blown away during strong winds. And, the plastic might degrade over time due to UV light.
Doors
You can choose between single and double doors depending on your shed’s purpose and style. Some people use large sheds in place of a garage, and you will need double doors for these. Sheds with two doors are more expensive than those with one because of the extra work involved when manufacturing.
Windows
Your shed may or may not require windows, depending on its purpose. If the shed is for storage alone, the window is unnecessary and reduces its security and privacy. However, if it is a workshop, potting shed or office, you need natural light from a window. But, buy one with opening windows for the summer months and invest in secure window fastenings.
Electricity
Usually, a basic shed won’t need electricity. But for specific functions such as a workshop or office, you will definitely need light and power. Although you might be tempted to use a trailing extension lead, rainwater and condensation from the air will make this very dangerous. Instead, choose permanent wiring connected to the house by a qualified electrician. Typically, an electrician charges around £40/hr plus materials, but a job like this won’t take very long. And, to make further savings, you can install the powerpoints and light fixture boxes yourself and ask the electrician to connect them.
How to Erect a Garden Shed
In the UK, you can buy all manner of sheds from garden centres and online speciality manufacturers, and they arrive at your house as a kit. Usually, you receive several panels, which comprise the floor, walls, door and roof, and all you have to do is assemble them. Shed erection is a piece of cake for the DIYer, or if you aren’t sure what to do, you can hire a professional to do the job.
Whichever route you take, you must start with a level base on which to build; otherwise, it’ll be hard work fitting everything together.
To help you decide which installation choice to make, we include the following steps for a shed erection.
Base
The base must always be level and stable and withstand the expected load from the weight of the shed and its contents.
The most straightforward base is a poured concrete option, which should take less than a day to complete.
- Choose the location for your shed, mark out the perimeter and add at least 200mm to each side. Then, the slab will extend at least 100mm from each wall when you’ve erected the shed in the middle of the slab.
- Remove turf and topsoil down to at least 100mm depth depending on the soil conditions.
- Place wooden boards or concrete block shuttering around the perimeter to contain the concrete. Ensure the shuttering top edge is level.
- Mix and pour the concrete into the prepared area up to the top of the shuttering. (if you intend to use the shed as a car garage, you will need steel reinforcing mesh placed in the concrete to spread the car’s weight).
- Tamp and level the concrete. Remove any hollows as you don’t want puddles to form.
- Finish the surface with a stiff brush to provide a non-slip, rough surface.
Shed erection
Manufacturers have their own ways of shed installation, so always follow the supplied instructions. The order of panel erection and method of fixing will vary depending on make, size, material and whether there are windows. So here, we’ll only concentrate on the general steps for putting up a shed.
- Place the base in the centre of the slab, with each edge parallel to the slab’s sides.
- Lift two panels that meet in a corner and place them on the floor panel. Ensure the wall panels are at 90 degrees to each other.
- Fix the two wall panels together and on the floor panel using the recommended method. Check each wall is vertical.
- Continue around the shed, add the other wall panels, and fix them as instructed.
- At each stage, check the walls are in line and level.
- Add the roof panels and fix them as instructed.
- Usually, sheds have strips to cover external joints. Now is the time to add these.
- Check all fixing screws are tight.
A typical shed installation shouldn’t take more than a few hours depending on its size, how many panels and how many fixing screws it has.
General Considerations
Building a shed is relatively easy if you can do DIY. However, to make life easier, you should consider a few factors before starting.
Location
Garden sheds are often used as workshops, potting sheds or used for storing paints and flammable solvents. Therefore, it’s a good idea to situate it in a shady part of the garden, so the interior doesn’t become too hot.
Access
Have the shed door near a garden path, so you don’t walk through mud during wet weather. If this isn’t possible, consider extending the existing garden path.
Trees and shrubs
Although the shed should be in the shade, avoid placing it directly below trees or overgrown shrubs. If necessary, cut these back before you start assembly. Garden plants such as these can prevent the shed from drying out properly after rain.
Gutters
If you can’t relocate the shed to a dry area, consider adding rainwater gutters to the roof. This stops rain from pooling on the concrete base and allows you to save and reuse rainwater in your garden.
Prevent rot
Allow enough room between the shed wall panels and surrounding shrubs and garden fences to allow good air circulation. Thus, keeping the shed dry and preventing rot. Also, raising the floor joists onto a course of bricks mortared onto the concrete slab will allow air circulation under the floor. Place a strip of damp-proof course between the brick and floor joists too.
Access
Good access around the shed allows you to maintain each wall and treat them with a suitable preservative.
Electricity
We’ve already talked a bit about supplying electricity to the shed. However, we must stress using a qualified electrician. They will use a suitably protected cable connecting the shed to the house. If the power supply goes underground in a trench, it must be an armoured cable or placed inside a protective sheath at the correct depth. If the cable is above ground, it must be enclosed in rigid protection to protect it from movement, UV light, and rain. The electrician will insist that the shed has its own residual current circuit breaker, and a separate fuse box, as all outdoors electricity should have. A qualified electrician knows the regulations concerning outside electricity and will insist on the installation complying with the rules.
Maintenance
Wooden sheds need the most maintenance. Cover the bare wood with a recognised preservative or good quality paint. Keep an eye on the exposed parts and repair rotten patches if necessary while re-preserving every year or so.
Metal and concrete sheds need very little maintenance. Probably, touch up the paint every year or so.
Finally, plastic sheds don’t require preserving or painting at all. However, cheap, low quality plastic sheds might be affected by UV light and become brittle over time.
Planning Permission & Building Control
Usually, Planning Permission for sheds and other outbuildings isn’t needed if they fall within the category of permitted development. This means that they must be lower than a certain height depending on the roof type; they must not lie within the curtilage of a listed building, must be single storey, and have an area of less than half the garden. You must also consider other requirements and ask your local planning department about the conditions in your area.
Building Regulations don’t usually apply to garden sheds as long as their floor area is below a specific size, don’t contain permanent sleeping accommodation and is at least 1m from a boundary or is fireproof. There are other restrictions, and you should ask your local Building Control office for advice.
Shed foundations must be strong enough to transmit the loads into the ground, not disturb neighbouring structures, or lie within 3m of a public sewer. Once again, check with your local Building Control office for further advice.
Shed floors also need to be strong enough to support the weight of the contents.
Part P of the Building Regulations deals with electrical safety. Electricity installation must comply with the current electrical installation regulations and be installed by a qualified electrician. You might need an armoured cable to protect the electricity supply, a separate fuse box in the shed, and an external residual current circuit breaker at the central consumer unit.
Some sheds or workshops require a mains water supply and drainage. All mains water installations must comply with the UK Water Regulations, and drainage must comply with Approved Document H of the Building Regulations. Registered plumbers know the applicable regulations, and you should use one to connect water to the shed.
Get Local Quotes
Building a shed in your garden isn’t rocket science. But, you must take into account a few basic instructions and guidance notes if you want it to last more than a few years. Furthermore, you must take note of the applicable Planning and Building Control restrictions and electrical, plumbing and drainage requirements if you intend to install these services.
Unfortunately, many people advertise themselves as shed fitters who don’t have the first idea of properly installing a shed. Therefore it’s always a good idea to use a qualified person for each aspect of the work.
Complete the form on this page, and we’ll ensure you get in touch with up to four reputable companies who will send you a quotation for properly erecting a shed.