ᐅ Cost Comparison: Insulated Ground Slab vs. Conventional Concrete Slab

Hello everyone,

I have a question for you.
If a roughly 130 m² (1,400 sq ft) insulated slab foundation for my planned house is estimated to cost about €35,000, would I possibly save money by going with a standard slab foundation including screed, underfloor heating, and whatever other accessories and membranes are necessary?
For a 30 cm (12 inches) thick slab, I would have about 39 m³ (51 cubic yards) of concrete. A contractor I know indirectly told me to expect around €80 per m³ (27 cubic yards) of concrete. That would be just over €3,000 in material. As far as I understand, he said I should budget roughly €6,000 to €8,000 for the entire slab foundation.

What does the screed cost? What about the underfloor heating?
What else is needed to make a fair price comparison with the insulated slab foundation?

I’m asking because I want to keep my costs as low as possible. To do that, I need some background knowledge so I can realistically assess whether the standard slab with everything included offers a genuine cost advantage.

Best regards,
titoz

Thermo means that the heating pipes are installed directly in the concrete slab? I knew this concept as thermal activation of the concrete core. In your version, is the floor covering laid directly on the vapor barrier? What about the pipes?

By the way, steel is added to the concrete as well, right?

titoz schrieb:
If my planned house has a roughly 130 m² (1400 sq ft) insulated ground slab estimated to cost around 35,000 €, would I possibly save money with a regular slab including screed, underfloor heating, and all the necessary accessories and membranes?

With a 30 cm (12 inch) thick slab, I would have about 39 m³ (51 yd³) of concrete. A contractor (who I know indirectly) told me to calculate with about 80 €/m³ (64 $/yd³) of concrete. So just over 3,000 € (3,500 $) for materials. As far as I know, he said I should expect roughly 6,000-8,000 € (7,000-9,400 $) for the slab.

Steel? What about frost protection footings? What about the insulation under the slab?

The much more important question is where your insulated slab is coming from. Is it from the same supplier as the house? If yes, can they not build a conventional slab?

If you have someone else install the slab, warranty might become an issue. It’s possible that the heating system planned for the house is specifically designed for the insulated slab. I believe it can operate effectively at even lower supply temperatures than underfloor heating embedded in screed.

https://www.hausbau-forum.de/threads/energiesparbodenplatte-Schwedenplatte-und-so.5684/

Also, take a look there as well.

Hello Tito

I paid just over €100 (about $110) net for the concrete for our slab.
I also don’t believe that a traditional concrete slab can be built for €6,000 to €8,000 (about $6,600 to $8,800).

You should ask for a fixed-price written quote for both options.

The advantages of the Swedish slab I see are:
no thermal bridges to the ground
no screed / no water inside the house
no expansion joints
no settling of the screed

Olli

I can list my costs here for a 250m² (2,690 sq ft) Sweden board floor done with self-performance.

Earthworks: sand, gravel 16 - 32mm (0.6 - 1.25 inches), crushed stone, separation fleece, drainage, crushed stone for driveway and terrace (280m² / 3,013 sq ft) 17,000.00€
Jakodur perimeter insulation 9,500€
Wastewater pipes 1,000€
Reinforcing steel and grounding 4,000€
Underfloor heating and manifolds 2,500€
Concrete 8,500€
Remaining earthworks by contractor, the rest self-performed.

Olli