Installing vinyl in a new building basement. How to make it waterproof?

Hello everyone,

we would like to have vinyl glued in the basement of our newly built house. The basement is constructed as a [weiße Wanne] and actually I do not expect any water in the basement, but you never know. In the laundry room, we have a floor drain in the middle.

The current floor structure is as follows:

[*]Perimeter insulation
[*]Floor slab
[*]Bitumen sealing membrane
[*]PU insulation
[*]Underfloor heating
[*]Cement screed

For the top layer, which is to be glued by the floor installer, the current plan is:

[*]Sanding the screed
[*]Primer
[*]Leveling compound
[*]Sand again??
[*]Glue vinyl

That way a little water (e.g., a bucket of water tipping over) wouldn’t be a problem, right?

But if water stands in the basement, it would be a problem at the edges of the walls, I suppose. Then you would have to proceed as in the bathroom and work with sealing tape and surface sealing? A considerable additional effort for the entire basement. Probably also exaggerated.

How would you do it? What should I consider?

Thank you all

Hello,

is this supposed to be installed as roll goods? If it is really supposed to be watertight, then you also have to have the seams between the rolls sealed. But if you already have a floor drain, what would have to happen for a swimming pool to suddenly form down there? Drain clogged and the washing machine connection breaks down during vacation? A bit far-fetched in my opinion, and if so, you have building insurance, which you have checked in advance for insurance coverage for such cases.

I wouldn’t do anything more about it. Maybe set up a water alarm next to the usual suspects like the washing machine. And for the tipping bucket of water, have baseboards with rubber sealing lips installed that prevent larger amounts of water from running into the screed.

Once had an unwanted swimming pool in the basement bathroom for a short time (washing machine supply line defective, leaked, room flooded about 30cm high) Vinyl was installed as a solid material, an early precursor to click (overlapped glued). After pumping out and drying, everything was as before. However, the walls were tiled all around, the vinyl laid WITHOUT a sealing joint at the edge. So some water got underneath. Way too much effort and thus costs. As the previous speaker stated, washing machine with water sensor and done.

Hello questioner. According to the structure you described, the drainage can only represent an "emergency drain." Assuming proper installation, the floor drain was certainly connected sealingly to the bitumen membrane. If a bucket of water spills over, this is fundamentally a "damage event not corresponding to contractual use." Such situations can occur anywhere in the house and do not have to be considered by special technical measures! Everything planned with "rubber sealing lips," etc., is rather a form of self-deception. Technically, this makes no sense at all! The described structure is planned for a room with elevated requirements: es ist ein Wohnraum geplant und so ausgeführt worden. And not a (usage subordinate) laundry room! When a bathroom is installed, the rules according to DIN 18534 apply. This means that a bathroom is to be classified in the water exposure class W1-I. This corresponds to the sealing over bathtubs and showers in bathrooms, floor surfaces in the domestic area with floor drains, and floor surfaces in bathrooms with and without drains without high water exposure from the shower area. The floor surfaces (and only those) in the shower itself fall into the next higher exposure class W2-I (floor surfaces with drains or channels). Here, wall surfaces and floors must be sealed accordingly (e.g., with liquid plastics) and the floor/wall transitions equipped with sealing tapes. But definitely not the entire floor level!!! To answer your last question: Yes, the screed surface must be sanded, dust vacuumed, and primed. Then the leveling compound, which is usually subjected to a cleaning sanding again (to remove resulting "pimples"). Only at this level are the sealing measures carried out. Also remember that sealing collars must be used at wall penetrations and integrated into the sealing layer!! ------------------ Good luck and success: KlaRa

Hello everyone,

thank you very much for your contributions.

Vinyl planks are to be laid, so nothing from the roll. It's not so much about a defective washing machine or something like that, but much more about a (minimal) flood risk and the associated ingress of water through the basement exterior door. There is a drain in front of it, whose pipe leads into the pump shaft. But if the sewage system should be full during heavy rain and the pump can no longer handle the water, meaning the pipe is full up to the backwater level, then of course the pump shaft will overflow or it will probably already push up at the highest point, namely the floor drain in the laundry room. How likely that is, I don't know, but extreme weather is increasing. A roof over the terrace and basement stairs would eliminate this weak point and is under consideration.

I will then, as mostly suggested by you, not plan anything further, no sealing lips etc. Normally, as mentioned, only some splash water, occasional small accidents etc. are to be expected, and then everything should be fine.

@ : Let's put it this way: If water really enters the floor structure due to heavy rainfall or from a washing machine, then you will – hopefully not! – have completely different problems regarding drying measures with a heated screed construction than just the top covering! In this respect, I would do everything (!) possible to close this security gap (flooding of the living space) immediately. It is then not enough to simply commission some remediation company to forcibly dry the insulation material (under the screed). What flows in from outside, to put it neutrally but understandably, does not have drinking water quality but is permeated with all sorts of things, solids as well as dissolved substances that you would not want to find in your cozy home. Usually, if the flooding comes from one of the sewage channels, a complete rebuild (meaning: dismantling the entire heated screed + insulation) will be necessary. Forced drying as a single measure will definitely not be successful! The scenario discussed here is not a theoretical case – but a practically possible one. That’s why my suggestion is to secure the water disposal against backflow first. --------- Regards: KlaRa