Garden Sheds in Sidcup

1. Mark out the area and dig the top layer of soil, trying to get the ground as flat as possible.
2. Build a timber frame to size.
3. Measure out 4 rows of 3 blocks to create good weight distribution and lay in place.
4. Underneath each block, dig around 50mm wider than the blocks and about 150mm deep. Fill the hole with pea gravel until it’s flat.
5. Place timber planks along the rows of blocks and see how level it is. Add or remove blocks where necessary. If it’s only a small difference, use shingle underneath the timber until it’s level.
6. Nail your timber shed base to the timber planks to create a sturdy base for your shed.

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.

Yes, it is possible to insulate a shed. You might want to do this if you’re planning on working in it during the winter. A professional will be able to help you find an insulated shed or advise you on how to insulate a shed that you already have. Always seek professional advise first before attempting to do this yourself!