Waterproofing/floor in laundry room

[j.e.o]

I am building an extension to the house and will have a laundry room as well as a utility entrance in the new part. The foundation is a poured slab. In the laundry room, there will be a washing machine, a sink, and a heat pump, distribution cabinet for underfloor heating, and a distribution cabinet for domestic water built into the wall, a floor drain is in place where there should be a local slope. I would like to keep the concrete as a surface finish. However, the industry regulations say that I should have a waterproof layer on the floor and a few cm up the wall. Can one polish and varnish the concrete floor, put a strip of waterproofing on the wall, and then some baseboard on top? Suggestions for other solutions?

 

[justusandersson]

The industry standards are designed by companies that want to sell as much tile and clinker as possible; they have no formal status. What applies are the BBR (Building Regulations by the Swedish National Board of Housing, Building and Planning). According to BBR, a waterproof layer is required for two reasons. 1) to prevent water from running into another space and 2) to prevent the surrounding construction (i.e., the walls in this context) from being damaged. In the latter case, the risk mainly depends on what material the walls are made of. If the walls are masonry and there are no adjacent spaces, you can disregard the waterproof layer. For wooden walls, some form of waterproofing is required. How the connection between the floor and wall is executed depends on the method you use. The simplest method is to use a fully welded plastic mat that is extended up onto the walls.

 

[j.e.o]

The industry rules are designed by companies that want to sell as much tile and clinker as possible, they have no formal status. What applies is the BBR (Swedish National Board of Housing, Building and Planning regulations). According to BBR, you should have a waterproofing membrane for two reasons. 1) to prevent water from flowing into another space and 2) to prevent the surrounding construction (i.e., the walls in this context) from being damaged. In the latter case, the risk depends primarily on what material the walls are made of. If the walls are masonry and there are no adjacent spaces, you can ignore the waterproofing. If they are wooden walls, some form of waterproofing is required. How the connection between the floor and the wall is made depends on the method you use. The simplest is to use a fully welded plastic mat that is extended up the walls.

Ok, my mistake. They are wooden walls and there are adjacent spaces. A mat is not an option. As I said, I want the concrete floor as a surface and the question was whether you can sand and varnish the floor, lay the waterproofing membrane 5-10 cm up the wall, and then have some baseboard. Perhaps I expressed myself unclearly; the question about other solution proposals was how to solve the waterproofing (and the joint between the floor and wall) while still having concrete as the surface on the floor.

 

[justusandersson]

One solution to this is to first create insulation between the outer edge of the concrete and the base of the wall, and then apply a thin layer of plaster on the floor that conceals parts of the insulation. The concrete can be made waterproof with specific agents. An alternative is to first lay a fully welded vinyl floor covering of suitable quality over the entire floor, extending up onto the bases, and then cast a thin concrete slab on top of it. If you reinforce the concrete with a suitable type of mesh, you can make it as thin as 40 mm.

 

[j.e.o]

One solution to this is first to create an insulation between the outer edge of the concrete and the base of the wall and then apply a thin layer of plaster on the floor that conceals parts of the insulation. The concrete can be made waterproof with special agents. An alternative is to first lay a fully welded plastic mat of appropriate quality over the entire floor, pulled up on the bases, and then pour a thin concrete slab on top of it. If you reinforce the concrete with a suitable form of mesh, you can make it as thin as 40 mm.

Nice that you're responding, but as I said, I want the concrete slab as the surface, no mat on it, no plaster on it, that kind of detracts from the whole aesthetics of a nicely polished concrete... I'm probably going to let the plasterboard stop a couple of cm above the floor and shove a thick silicone sealant under the edge of the plasterboard and then a baseboard on the outside.

 

[justusandersson]

I don't think it will be tight in the long run. It hardly meets the requirements in BBR either. The only way to achieve what you want is to do the waterproofing first, properly pulled up on the sides, and then cast the slab.

 

[hoffret]

kind of you to reply, but as I said I want the concrete slab as a surface layer, no carpet on it, no plaster on it, it somewhat detracts from the whole aesthetic of a nicely polished concrete....
I will probably let the plaster stop a couple of cm above the floor and press a thick silicone seal under the plaster edge and then a baseboard outside

I'm facing exactly the same dilemma as you!
What solution did you end up with in the end?

 

[Henrik.woll]

You can apply the waterproofing layer and then cast a concrete slab on this, which becomes the final surface layer, thus meeting the requirements.

 

[j.e.o]

I'm facing exactly the same dilemma as you!
What solution did you end up with?

I left a gap from the concrete floor up to the boards and filled it with an insane amount of silicone, then placed a skirting board on top of that. I polished the concrete and treated it with some stone polish that isn't diffusion-tight. Checked this with my KA and he saw no major problems with it.

 

[hoffret]

Okay, so you completely skipped the waterproofing layer on the floor and also the upturn on the wall?

 

[Ladan vid havet]

I left a gap from the concrete floor up to the boards and filled it with an insane amount of silicone, then placed a baseboard on top of that. I sanded the concrete and treated it with some stone polish that isn't diffusion-tight. Checked this with my KA and he didn't see any major problems with it.

I'm considering something similar. We will pour in January when the weather allows. If you disregard BBR, then practically there shouldn't be any problem. Either do as you did or alternatively glue some metal strip to the floor, seal, and then baseboard on top of that. If there's a substantial flood, the thresholds are the weakest points anyway.

But it's really what KA and BBR say that might put a stop to it.

 

[j.e.o]

Ok, so you completely skipped the waterproofing on the floor and also the flashing on the wall?

Yes, that's correct