Concrete foundation

Concrete foundation with graduation

A reinforced concrete slab on a gravel base is a high-quality foundation option.
Dig below the frost line (approx. 60 – 80 cm deep, depending on the region), then fill and compact the excavated area with gravel (grain size up to 35 mm). Then level with gravel (grain size up to 6 mm) up to a thickness of approx. 3-5 cm. The vapour barrier (plastic membrane at least 150 μm thick) is laid in this levelling fill. The concrete foundation with 1 to 2 layers of structural steel grid is placed on top of this. The concrete slab should be approx. 10 - 15 cm thick.

The graduated foundation slab, with a circumferential step of 2 x 7 cm, is an ideal design. The floor profile is attached to the surface using the screws and dowels supplied.

Please note that it is not possible to use the aluminium floor frame with the graduated concrete foundation. A sealant can also not be applied to protect against water ingress.

Work steps

1. Frost-proof excavation of the building site
2. Construct the gravel base
3. Apply levelling fill
4. Lay vapour barrier
5. Pour the foundation

Alternative: level concrete slab without step

As an alternative to the stepped concrete foundation, a continuous flat concrete slab can also be poured.

The installation is carried out (up to the foundation step) as per the concrete foundation described above with the offset foundation slab.

The aluminium floor frame available as an accessory makes it easier to level out any unevenness in the ground and to apply the sealing joint. The aluminium floor panel (lined with XPS hard foam boards 2-3 cm thick) can be attached using the aluminium floor frame.

Work steps

1. Frost-proof excavation of the building site
2. Lay the gravel base
3. Lay levelling fill
4. Lay vapour barrier
5. Pour foundation

Please also note the above-mentioned concrete foundation plans for this option.