Sheds are popular additions to gardens and putting them up shouldn’t be too difficult, providing manufacturers’ instructions are followed. Most DIY stores and garden centres will have a good selection of sheds and summer houses to look at.
The most important part of the process is to make sure the base is solid and level. The easiest way of achieving this is to put down a concrete slab or some paving slabs. If dealing with concrete is a bit outside your DIY comfort zone you can get away without it for a small shed.
Temporary Bases for Small Sheds
For a shed up to about eight feet by six feet you can put down loose paving slabs as long as they are level. The best option is to roughly level the ground and put down a bed of gravel, shingle or crushed hardcore. Then place the slabs down and level them, making sure that none of the beams of the shed floor will be over the gaps between slabs.
You can also lay stout, treated timbers across a similar bed of rubble rather than paving slabs. Just make sure that there are enough of them to have gaps of less than eighteen inches between each timber. Bear in mind that whether you use paving slabs or timber the shed will almost certainly shift slightly and warp over time, but if it’s only being used for storage this shouldn’t be a major concern.
Concrete and Paving Slab Bases
For larger sheds or ones that you are looking to spend time in yourself, a concrete slab or properly laid base is best. In both cases you want to make the base slightly smaller than the wooden floor of the shed (about half an inch smaller all round) otherwise rain water running down the sides will creep between the floor and the base.
One lesson gained from experience is not to rely on the manufacturers’ measurements for the base. Wait until it’s delivered to be doubly sure unless you happen to have a disc cutter strong enough for concrete hanging about!
Strip away any turf or plants and roughly level the surface. Don’t worry too much about digging down as lifting the shed a few inches off ground will help water drain away from the shed. Lay down a layer of hardcore, breaking up and large lumps, then compact and roughly level this layer.
You’ll find more details on concrete mixes in our article on concrete in this section, so we’ll just cover the basics here. If you are making a one-piece concrete slab build a framework of planks around the edge to contain the concrete, high enough for a slab three to four inches thick. You’ll need one part cement to two parts sharp sand and three of aggregate, adding water to a pouring consistency. Pour it in and spread and level.
For paving slabs prepare a dry mix of four-to-one sand to concrete. Spread this over the prepared ground to a depth of one to two inches and roughly level it. Then lay the paving slabs, levelling each one with a rubber mallet and spirit level.
Putting the Shed Up
While the concrete dries, get the preservative out and brush every part of the shed. If you want to paint it too, now is the time. Once the base is ready, make up and lay the floor. It’s now definitely time to find a helper or two for the next bits.
Not all sheds are assembled in the same way so follow the manufacturers’ instructions if they are different. Most start with raising the rear end of the shed first, screwing it to the floor, doing the same with one of the sides and joining the two together. If you have a side with no windows, do that one first as it will flex less.
You should now be able to let go and put the other side and the front on, checking that everything is vertical as you go. Put the roof panels on next and lay whatever roofing material you have chosen. If it’s roofing felt, make sure there are generous overlaps and use plenty of tacks.
Completing the Job
The last bit will be fitting the door and windows and again you will need to use the manufacturers’ instructions as sheds differ widely. Definitely leave the windows till last though, as a mistake earlier in the build might lead to a cracked window which is a real pain, even if it’s plastic.
Then step back, admire your work and start filling it with all the stuff you haven’t been able to put away for ages!