Basement
Thermal insulation of foundations / the foundation slab
To protect the building from the cold, we recommend our Austrotherm XPS TOP 30 wherever the building is in contact with the cold ground — above all at the foundations.
There are many opportunities for unwanted thermal bridges at the foundations, which is why insulating them properly is so important.
Since 2011 Serbia too has set strict maximum U-values ("Umax"): Umax = 0.30 W/(m²K) for new buildings and Umax = 0.40 W/(m²K) for refurbishment. This applies to buildings with standard insulation; for low-energy houses at least 10 cm of insulation is recommended, for passive houses at least 20 cm.
For special requirements we also offer Austrotherm XPS TOP 50 and Austrotherm XPS TOP 70, with even higher compressive resistance (18 t/m² and even 25 t/m²!) and even better (lower) thermal conductivity. These products have been made in Serbia, in our XPS plant in Niš, since 2010.
Here are sketches of how to insulate a basement, with a foundation slab or with strip foundations, depending on whether the building has a basement storey:
Recommended products
XPS TOPAustrotherm XPS TOP 30
Thermal insulation board of extruded polystyrene with a smooth surface
- Compressive strength
- 300 kPa
- Permitted load (2%)
- 130 kPa
- Fire class
- E
XPS TOPAustrotherm XPS TOP 50
Thermal insulation board of extruded polystyrene with a smooth surface
- Compressive strength
- 500 kPa
- Permitted load (2%)
- 180 kPa
- Fire class
- E
XPS TOPAustrotherm XPS TOP 70
Thermal insulation board of extruded polystyrene with a smooth surface.
- Compressive strength
- 700 kPa
- Permitted load (2%)
- 250 kPa
- Fire class
- E
Insulation & formwork: the Austrotherm insulation system for foundations
Our colleagues at the group's head office in Austria have launched on the Austrian market a foundation insulation system that is also a formwork system and meets the strictest requirements for compressive strength and water absorption. It is designed for foundations and foundation slabs of residential and industrial buildings, car parks etc. Particular attention is paid to keeping moisture out of the basement, through a standardised connection of the horizontal and vertical waterproofing. The whole building is thus wrapped in one thermal envelope with no risk of harmful thermal bridges.
Insulation advisor
Describe the job — get the right boards
Tell us what you are insulating and with what. The advisor picks from Austrotherm products only and quotes our own data; the site then works out the packs.
- Describe the building element and the situation
- Get the element, the boards and the open questions
- Calculate packs and the indicative thickness
Indicative calculation
How many packs?
Packs from our own packing lists: area ÷ m² per pack, rounded up. With a target U-value the calculator shows the indicative insulation thickness d = λ × R.
Enter the area to see the number of packs.
Indicative only — the final choice and thickness are confirmed by your designer or Austrotherm technical support. The thickness estimate takes the insulation layer alone (R = 1/U) and does not check any regulation.
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Private customers and contractors
We sell wholesale only. Our products are on sale at hundreds of building-material dealers in Serbia and Montenegro.
Building-material dealers
Registered companies order directly from us — with the order form and the current price list.