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As the best insulator is trapped air, the insulating capacity of a material is basically created by a structure containing a multitude of tiny air pockets. There is a simple rule: the heavier the material, the less it insulates; the lighter it is, the better it insulates.

  • Non-insulating materials
  • In general, all load-bearing materials, such as concrete blocks, earth masonry, stone, joists, etc.

  • Poor insulators
  • This group includes all lightweight building materials, such as Argex, Poroton terracotta blocks, etc.

  • Medium insulators
  • These materials are heavy but contain a high proportion of air: cellular concrete blocks, wooden planks, etc. Used thickly, they can meet insulation standards.

  • Effective insulators
  • Characterised by their lightness, they contain a high proportion of trapped air and should be considered the only 'insulating materials' in the true sense: mineral wool, extruded polystyrene, expanded polystyrene, cellulose acetate flakes, hemp wool, cellular glass, polyurethane foam, Resol foam, etc.

Recommended thicknesses:

If you are thinking about building, here are some practical tips:

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