Foundation insulation

Sealed thanks to spray foam

The foundation of the house should be sufficiently insulated so that no heat is lost through the building components in contact with the ground. With foundation insulation as part of an energy efficiency renovation, you prevent unnecessary thermal bridges in this area and help the house to cool down less quickly. Depending on the location and nature of the foundation, base insulation and perimeter insulation can significantly reduce heating costs.

Since the upper part of the building is also connected to that of the basement, the insulation does not only protect the lower floor. It protects the entire building against frost, moisture and thus also against mould formation. The base insulation is carried out up to approx. 80 cm below the ground and reduces the formation of thermal bridges between the outer wall and the foundation in this area.

Even if the foundation insulation is more complex than the interior insulation of the basement walls – outer insulation is particularly advantageous due to the prevention of thermal bridges in the area of the transition from the basement to the heated living rooms. In addition, perimeter insulation is indispensable if the basement is used as living space.

Benefits of foundation insulation

  • Insulates effectively and prevents the walls from excessive cooling
  • Reduces heating costs significantly
  • Prevents moisture and mould damage
  • Reduces the risk of dry rot
  • Allows the basement to be used as living space

Thermal insulation process

We recommend the tried and tested EXY spray foam insulation to insulate the base. The foam is simply applied to the cleaned surfaces of the base and plays out its thermal insulation properties after expansion. The foam reaches up to 30 times the volume of the discharged amount. As a result, the foam settles as a homogeneous mass in almost all cracks and more open spots in masonry and concrete, thus preventing heat from escaping. The insulating foam hardens within a few minutes after application and can be further processed right away – so you can apply bitumen immediately after curing to give the building extra protection from water.

Useful tips

A general rule is to ensure that all basement walls are insulated with the same level of insulation. This is the only way to prevent a cold bridge from forming in the less well-insulated areas, which can lead to the formation of condensed water. It is also advisable that the base insulation does not protrude in front of the façade insulation. Otherwise, rain could penetrate the base insulation from the façade.


EXY 09:
Tried and tested! Effective and very breathable due to its open-cell structure.
One of the most effective insulation materials available on the market. The new generation EXY 34 HFO.


Protect your house effectively from moisture and save on heating costs – with high-quality base insulation. We would be happy to advise you. 

Further information

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