Below grade perimeter walls (as in cellars) can be insulated by filling all of the V shaped part of the excavation with Laterlite Plus Expanded Clay (granule size 8-20) wrapped with a geotextile.
In new buildings with straight, regular walls, a layer of Laterlite Plus Expanded Clay of constant thickness can be also created by using Termobag modules that function as an underground external wall insulation that is free of thermal bridges and is continuous with the horizontal ground insulation (for further information please refer to the specific section).
A drain shall be placed at the base of the Laterlite Plus layer in a similar manner to a traditional drainage solution.
In new buildings, the insulation basement walls with Laterlite Plus backfill can be put in continuity with the insulation of the foundations to eliminate any thermal bridging. This solution is particularly interesting for buildings with high energy performance such as passive houses.
This construction method is particularly appropriate for underground spaces where there are problems of damp; the damp ground in contact with the wall is replaced by the expanded clay, which is a dry and non-capillary material that reduces the risk of infiltration.
The same method is equally straightforward to apply in the case of walls that are irregular or non-planar (e.g., in historic buildings) since unlike insulating rigid panel systems, expanded clay easily adapts to these situations and does not produce waste or leftover material.
The solution has similarities with the traditional gravel perimeter backfill but provides the insulating and damp control properties of Laterlite Plus aggregate, being highly recommended for renovations and interventions in historical buildings and monuments, or in ecological construction.
The same method is also frequently used for swimming pools to reduce thermal dispersion and ground pressure on the walls (for further information please refer to the geotechnics section).
This method will protect any waterproofing or other vulnerable layers (such as insulation) from damage due to impact or sharp stones during construction or over the life of the building.
Earth pressure reduction on basement walls
As well as providing thermal insulation and drainage, this also reduces the horizontal ground thrust on the wall by up to 85% (for further information please refer to the geotechnics section).
Laterlite Plus insulation backfill is mineral and non-combustible (Euroclass A1), highly breathable, pest-resistant, rot-proof and frost-resistant.