Garden shed: the right substructure ensures stability

Garden shed: the right substructure ensures stability

Which foundation is suitable?

Before you decide on one of the substructures listed below, it is important to take a close look at the subsurface:

  • How thick is the existing humus layer, how compact is it?
  • What types of soil are there, for example is the soil sandy or loamy?
  • Is the terrain completely flat?
  • How can you get to the construction site? Ideally, could the substructure be delivered directly?

also read

  • Anchoring the garden shed well: A foundation ensures stability
  • The right foundation for the garden house
  • Does a garden path always need a substructure?

The foundation plate: Quite easy to make yourself

Since the load of the garden shed is distributed over a large area, this is the ideal solution if the floor does not offer good stability. The slab foundation is manufactured as follows:

  • Dig a pit about forty centimeters deep, which must be about ten centimeters larger all around than the planned garden shed. (7.70 € at Amazon *)
  • Stabilize the edges with formwork.
  • Fill up about halfway with gravel, which is then compacted with a vibrating plate (€ 214.60 at Amazon *).
  • A PE film is laid on top to protect the concrete from frost damage and moisture.
  • Fill with concrete in two layers, separated by a steel mat.
  • Straighten them horizontally using a puller.

The intelligent construction of the strip foundation saves concrete

With this substructure, concrete is only poured under the outer walls of the garden house, but the ground must be dug at least seventy centimeters deep for the trench required for this. The actual floor slab of the house can thus remain much thinner.

The point foundation

This is not that uncomplicated to plan for the layperson, because the point foundation for the garden house is usually formed from nine small individual foundations. This requires square holes forty centimeters long and at least eighty centimeters deep. These are boarded up and filled with concrete. This substructure often does not have an additional base plate.

The plate foundation: quick and easy to erect

This consists of individual pavement slabs that are laid in a gravel bed. This simple substructure is only suitable for smaller garden houses that do not have to withstand great loads. The construction is quite simple:

  • Dig the soil at least a foot deep.
  • Put in a layer of gravel about 25 centimeters thick and compact it using a vibrating plate.
  • A five-centimeter-thick layer of gravel is placed on top to compensate for the height.
  • Lay the concrete slab with joints of around five millimeters.
  • These are filled with silver or quartz sand (€ 14.90 at Amazon *) and thus stabilized.

Long drying times are no longer necessary, the metal substructure of the garden house can be anchored directly afterwards on the slab foundation.


Regardless of which substructure you choose, plan any power lines and pipes for sanitary systems that may be required in advance.