How to Build a Shed Base

How to build a shed baseWithout the correct installation of a shed base, erecting a garden building can prove to be very tricky. It is extremely important that all sheds are constructed on a firm and level base which is constructed from the appropriate, durable material. Assembling the shed base incorrectly can lead to future deterioration of the product such as doors dropping out of square, thus becoming complicated to repair or leading to water leakage.

Note: The incorrect assembly of a garden building on an incorrect shed base is also likely to void any guarantee that may come with your shed



Find the right location for your base

There are a few things you must take into account when choosing where to place your shed, whether you have a shed in Kent or in the Scottish highlands, it is important to find the right location to build your shed base. 

First of all, always remember that placing the base too close to any walls, fences or other objects may cause problems. Some sheds have overhanging roofs, which could also prove a problem. The same goes for trees, large bushes or major plant life. Branches are likely to grow and come into contact with your structure, so do your best to avoid these when building a shed base

So you have assembled your shed. Check for overhanging foliage regularly as any rubbing on the roofing felt may well lead to your shed becoming vulnerable to damage from adverse weather conditions and even rain.

On top of this, check that the best location in your garden allows the easiest access, including the side of the shed in order to apply treatment to your shed. Have a visual image in your head; you may not want to carry heavy objects to and from the bottom of your garden. For our summerhouses, you may want to consider whereabouts in your garden there is the best access to natural light or even the best view.

Finish off deciding on location by gathering whether you intend to fit an electricity or water supply.  Remember to cater for the distance to mains electricity and water supply.

Time to build your Shed Base

Depending on your ability, we recommend using a local builder, the quickest and simplest way to achieve a shed base with maximum durability and longevity.

However, for the DIY enthusiast, if you do wish to construct your own shed base, then follow the guide below using the suitable material of your choice.

Step-by-step Guide to Building your Shed Base:


There are three main methods used to build a shed base, these are: A CONCRETE BASEA PAVING SLAB BASEA TIMBER FRAMED BASE

It is important that you build your base to the exact size of your building. All ACE buildings are manufactured with imperial measurements eg. 8x6 is exactly 8'x 6' not  2400mmx 1800mm like most shed companies. This means that the floor sits exactly on the base and you won't get the inevitable splash-back from a larger base.

How to Build a Concrete Shed Base

  1. One of the strongest options out of the three, concrete bases are ideal for providing a truly permanent foundation for your garden building. While wooden bases can require more upkeep over the years, the use of a solid material when building a shed base can ensure that your shed is in top-condition for the following years. Using wooden pegs and string, mark out the desired base size adding 2" to each length, for example: for an 8x6 base you would need to string mark 8'2"x6'2". Measure from corner to corner to ensure the area marked out is square. The concrete base can be level with the surrounding soil or raised above. If you require a level with the ground base you need to excavate the area to a depth of around 6" to allow for 3" of hardcore/sub-base and 3" of concrete. Level the area with a rake and remove the pegs and string. 
  2. Next, you will need to insert wooden shuttering or formwork around the edges of your excavated area. This will need to be made from 6"x1" timber and screwed or nailed into position. If need be, you can include wooden pegs to form a square, level solid formwork to hold back the hardcore and concrete (in the next step). The reason for the original excavation to be 2" bigger all the way around is to take into consideration the wooden frame, you will now have an internal area of 8"x6". If you decide to use thicker timber you will need to take this into consideration at the stringing out stage.
  3.  You now need to add the hardcore/substrate to a depth of 3". Ensure after you add the hardcore or substrate you level it and compact the subbase down. 
  4.  If you do not require a shed floor it would be advisable at this stage to add a damp proof membrane, this can be laid on top of the hardcore ready for the concrete. A concrete mix of 5 parts ballast and 1 part cement should now be mixed and poured into the area, enough concrete should be poured so that it is just proud of the formwork. It can now be tampered down level and flat using a straight piece of solid timber. The result should be a smooth level concrete base - the ultimate shed base.
  5. As you will be building a shed base from concrete, you can choose to either purchase a ready-mixed option for ease or create your own mix from sand, water and cement, with cement to sand ratio of 1:5. 
  6. A concrete mix of 5 parts ballast and 1 part cement should now be mixed and poured into the area, enough concrete should be poured so that it is just proud of the formwork. It can now be tampered down level and flat using a straight piece of solid timber. The result should be a smooth level concrete base - the ultimate shed base.


How to Lay a Shed Base with Paving Slabs

A highly versatile material to use when building a shed base, paving slabs provide a perfect foundation for greenhouses, log cabins, standard garden sheds, playhouses, summer houses and more. While concrete may require more levelling, paving slabs can be purchased already levelled and cut to size. 

  1. Using wooden pegs and string, mark out the exact base size required, being careful to measure both diagonals in order to get the area square. This area can now be excavated to a depth of 3". This depth can vary depending on the thickness of the slab used and the gradient of the ground excavated. Overall you're looking to achieve a thickness of 4-5cm of sand/cement mix and the slab on top.
  2. A dry mix of building sand and cement, approx. 8 parts sand and 1 part cement can now be levelled into the area.
  3. Starting in one corner and working outwards you lay the slabs and level as you go with a rubber mallet and spirit level until the area is fully covered. 
  4. You may need to space the slabs in order to achieve the correct size of the base in which case you will need to brush into the gaps the dry mixed-used earlier, alternatively, you can butt the slabs uptight and cut the slabs to fit.








How to Build a Wooden Shed Base

A relatively inexpensive choice out of the three options, a wooden shed base can be installed easily. Ideal for smaller structures such as playhouses, summer houses as well as garden sheds. Building a shed base out of wood such as timber can be beneficial as it raises the floor of the shed off the ground and extends the lifespan of your investment. 

  1. Using wooden pegs and string, mark out the exact based required, being careful to measure both diagonals in order to achieve a square area.
  2. Strip the grass or excavate soil to 2" deep and rake the ground level.
  3. Fill the excavated area with pea shingle.
  4. Either purchase a bearer base from us or you can build your own using 3"x2" treated timber. This wooden frame can then be levelled into the pea shingle for a well-drained wooden base.
  5. If you decide to build your own wooden base it is important that you contact us to find out which way our floor runners go in order to make your frame doesn't run the same way. 



Although the above base ideas are the most common, some of our customers have used alternative construction methods and materials like wooden sleepers and concrete fence posts. Whichever material you decide to use when building your shed base,  it is important that the floor has enough support the entire length of the building and this support has to be level and flat.

Good luck, and don't forget that you are only a phone call away from our expert team who can offer you advice and help where necessary. all our experts on 01233 822042 or contact us online.

If you're looking for a premium-quality, bespoke shed to go on top of your newly built shed base, you can find a range of sheds from:

Garden Sheds            Corner Sheds            Potting Sheds            Pent Sheds            Workshops            Summerhouses            Security Sheds            Wooden Garages        


Contact us
Contact us