Envelope structure composition
Skladba stěny

ATREA energy-passive houses are designed as skeleton sandwich structures (the so-called Scandinavian system) with a diffusion-open envelope.
Almost the entire thickness of the wall is used for thermal insulation. Most of the structure’s materials are wood-based, that is from a renewable material with the low energy demand of production, transportation and structural assembly. All structural details in the ATREA system are carefully designed and verified in terms of easy and fast construction and subsequent inspection. All details have also been verified by calculations for heat flows, internal surface temperatures and water vapour diffusion.

Description of individual material structures

Thermal and technical parameters of envelope structures
Tepelné parametry a těsnost obalových konstrukcí EPD ATREA
  • Foundation structure – Concrete foundation strips.
  • Outer walls – A diffusion-open sandwich composition, skeleton structure.
    • The wall thickness is 450 mm with façade rendering and 490 mm with larch cladding.
    • Load bearing structure – A frame from wooden KVH profiles dried to 12 % to ensure the shape stability of the structure.
    • Thermal insulation – Blown cellulose made using the paper defibering method, with very good accumulation properties and enabling water vapour diffusion.
    • Air-tightness layer – Oriented strand board (OSB) with bonded and glued joints to prevent warm indoor air from escaping and stop water vapours from permeating into the structure.
    • Interior surfaces – A plasterboard pre-wall with an installation cavity for utilities. Other board materials such as plaster fibre can also be used.
    • Exterior surfaces – Thin-layer diffusion-open rendering, larch-wood cladding, cement-fibre board cladding etc.
    • Heat permeability coefficient – U = 0.11 W/m2K.
    • Fire resistance – REI 60
  • Roof – A slanted or flat, double-skin, aired structure.
    • Load-bearing frame – Girders from KVH profiles.
    • Thermal insulation – Blown cellulose
    • Air-tightness layer – Oriented strand board (OSB)
    • Interior surfaces – A plasterboard false ceiling with an installation cavity for utilities. Other board materials such as plaster fibre can also be used.
    • Slanted roof covering – Black or grey cement-fibre ETERNIT DAKORA as standard. A choice of all known covering materials depending on the surrounding built-up area.
    • Flat roof covering – Welded PVC foil with pebble stone or substrate with extensive greenery.
  • Windows
    • Triple glazing wooden vertical windows – Eurookna SOLID COMFORT SC 92 – Uw = 0.7 W/m2K..
    • Triple glazing wooden skylights – ROTO design R6, Uw = 0.84 W/m2K..