Perimeter thermal insulation of basement walls below ground level

Requirements of thermal insulation and the climate inside the basement rooms are higher than ever before. Insulation of basements contribute to a pleasant and healthy living climate. An optimal thermal insulation of all basement walls on their external sides is a big issue for reducing the main causes of earth warming-up with CO2 emissions. Furthermore, this investment will be worthy due to the reduced consumption of heating energy. Last and not least extruded insulation boards protect the waterproofing layers from external influences. It increases the life span of building and increases its value. Perimeter insulation can be installed on new and also on old buildings.

Step by step


    1. Lay the insulation boards starting at the bottom of basement walls. Boards must lay firmly on the forepart of the concrete slab. Their bonding is done after full drying of the previous bitumen water-proofing layers either dotwise in case of non-pressure water or full-surface in case of pressure water according to the buttering floating method, i.e. the glue material is applied on the substrate and also on the backside of the boards.


    2. In case of water pressure apply the bitumen all around the stage rabbet of boards in order to avoid any backwards humidity penetration.



    3. Whenever a thermal insulation of water-impermeable concrete structures below ground level is necessary, the bonding of insulation boards is done according to the buttering floating method. Use the bitumen primer weber.tec 901 diluted 1 : 1 with water on the substrate and apply a scratch layer of bitumen in a thickness of approx. 1 - 2 mm.


    4. Lay the rigid insulation boards onto the fresh scratch layer in order to obtain full-surface bonding.


    5. The insulation of the socket part provides a transition between the earth-contacting insulation material and the ETICS (external thermal insulation composite system) on the facade.