Garden Sheds in Dorchester

• The shed doesn’t cover more than 50% of the garden
• It’s not in front of your house
• The shed is single-storey with eaves no higher than 2.5m and the overall height is no taller than 4m for a dual-pitched roof, or 3m for any other type. If it’s located within 2 metres of your property’s boundary, it mustn't be more than 2.5m high
• There’s no veranda or balcony
• The floor area is no bigger than 15m² - up to 30m² may be covered under Permitted Development if other conditions are met
• The shed is for domestic use only by those who live in the property and there’s no sleeping accommodation – that means you can’t run a business from the shed unless you apply for planning permission

• If you live in a listed building, you’ll need Listed Building Consent before you can build a shed in your garden
• If you live in a conservation area or similar, the maximum area of ground covered by outbuildings, pools and enclosures situated more than 20m from any wall of the house mustn’t exceed 10m² if they’re to be considered as a permitted development
• If you own a piece of woodland, you must seek planning permission for any permanent structure
• In Scotland, you’ll need planning permission if any part of the shed comes within 1m of a neighbouring property or is more than 2.5m high
• In Northern Ireland, there are rules about how close your shed can be from a road that passes by the back of your house. It’s best to check for clarification

1. Plan your shed base You must have a sturdy base for your shed, otherwise the frame won’t stand properly and could stop the door from opening. Decide whether you’re going to have:
   • A concrete base laid on hardcore
   • Concrete slabs on sharp sand
   • Treated wood beams on hardcore or shingle
   • An interlocking plastic system
   All bases should be laid on firm, level ground as far as possible.
2. Treat wood with preservative To help your shed last as long as possible, you should coat all the wooden parts with timber preservative before you put it together.
3. Put the shed floor together Some will need more assembly than others, but you need to make sure that the floor panel is attached to the joists; follow the manufacturer’s instructions for the correct spacing.
4. Put up the shed walls
   • Mark the centre point of each wall on its bottom edge, then do the same for the shed floor so you can line them up together.
   • Stand the gable end on the base and line it up. Check that it’s vertical with a spirit level – you might need someone to support the panel while you do this. Use a temporary holding batten to keep it in place.
   • Fix a side panel to the gable end panel with countersunk screws, then add the second side panel in the same way.
   Don’t attach the panels to the floor until you’ve fitted your shed roof.
5. Fit the roof
   • If the shed comes with a support bar, put this in position before you put the roof panels in.
   • Nail the roof panels in place, ensuring there’s a parallel and equal overlap at each end.
   • Roll out some roofing felt from front to back, leaving a 50mm overlap at each side. Secure it with clout-headed felt tacks at 100mm intervals.
   • Apply mastic sealant to the outside corners, then fix each corner trim with 30mm nails.
   • Add the fascias and finials, predrilling 2mm holes to avoid splitting the wood. Nail them through the felt into the shed using 40mm nails.
6. Add the shed windows
   • Slide each windowsill into the tongue and groove cut out, then put the window cover strip in position, fixing it to the vertical framing.
   • From inside the shed, put the glazing sheets into the window rebates, making sure the bottom edge of the glazing sheets sit on the outside of the sill.
   • Fix the window beading on the top and sides with 25mm nails.
7. Fix the walls to the floor Before you do anything, make sure you check that the centre marks on the walls line up with the marks on the shed floor. Then fix the wall panels to the floor with 50mm screws, aligning them with the joists.
And that’s it! But if you’re not confident in building a shed yourself, there are plenty of professionals available who will be happy to help.

Yes, your shed does need a base. This is to give it a solid, level foundation. Open soil will not help with the longevity of the shed itself or the contents within. The best materials to use to make your shed base are concrete, natural stone or wood.