EPS Concrete on wooden joists, thickness?

[TechChad]

If I were to use grooved particle board and one layer of floor gypsum, would that be enough, or is two layers of gypsum needed? I'm planning to use studs at 300mm centers.

 

[useless]

What surface finish will you have?

 

[TechChad]

Ceramic tiles large slabs 600x600mm approximately 1cm thick

 

[nino]

Glue gypsum with s48, it holds with one layer.

 

[justusandersson]

The density for EPS concrete is 480 kg/m3. Although this is indeed a little compared to regular concrete which is 2300 kg/m3, it is not negligible. Self-leveling compound has a density of 2200 kg/m3 in its fresh state. Tiles have the same density as concrete. Therefore, a 1 cm thick slab weighs 23 kg/sqm. Sum up all the weights per square meter with the respective thicknesses and see what you come up with. Add a useful load of 200 kg/sqm to that.

 

[TechChad]

I will probably go with a layer of gypsum. However, Ardex s48 is quite expensive. Does anyone know if there is a cheaper alternative?

 

[nino]

Have never used anything else, have never had a complaint so far either...

But there are probably almost as good copies

 

[TechChad]

I think I have decided how to proceed:
I will space the joists at 300mm with 45x70mm, screw-glue 22mm grooved chipboard.
Attach a layer of gypsum floorboard with Bostik Rep & Fix (instead of Ardex S48). Then lay the tiles.
Any objections to this, simplifications/errors in my setup?


I thank everyone very much for all the helpful responses, and for taking the time to help me!

 

[Rabbithole]

Should be fine. If you have extra space, increase the height of the studs.

 

[Peter2400]

I think I have now decided how to proceed:
I will cross batten cc 300mm with 45x70mm, screw-glue 22mm grooved chipboard.
Attach a layer of floor gypsum with Bostik Rep & Fix (instead of Ardex S48). Then apply the tiles.
Any objections to this, simplifications/errors in my setup?

I thank you very much for everyone's helpful responses, and for taking the time to help me!

Kiilto has a description where they use their flow adhesive instead, significantly cheaper than Bostik.
http://www.kiilto.se/files/attachme...uren_golvvarme_i_sparskiva_pa_trabjalklag.pdf

 

[TechChad]

Yes, but you probably also need their fixbinder? 5 liters of fixbinder for 20 kg gives about 5 sqm, right?

 

[Peter2400]

Yes, but you need to have their fixbinder too, right? 5 liters of fixbinder for 20kg gives about 5 sqm, doesn't it?

Missed that, are you going to use heat distribution plates? They're necessary if you're laying the pipe in grooved chipboard, right?

 

[TechChad]

Yep, I'll use heat plates, screw them, and wash with denatured alcohol.

 

[justusandersson]

I'm shortening cc 300mm with 45x70mm

Note that kortlingar do not increase the load-bearing capacity of the flooring structure at all. It can help reduce the effect of point loads and increase the stiffness of the flooring structure.

 

[TechChad]

Note that nogging does not increase the load-bearing capacity of the joist at all. It can help reduce the effect of point loads and increase the stiffness of the joist.

No, but according to, for example, the link Peter2400 linked to, it's okay with 600cc. I'm installing nogging to increase the stiffness and also try to get the floor as level as possible.