Furnish basement and stairs down

[Tvapac]

The previous owner extended the house 10 years ago. During the extension, a basement roughly the size of the old one, about 30 sqm, was added. It is half under porous-drained ground, and half above with basement windows. There are sewage and water, the floor is roughly cast, OSB, and gypsum on walls and ceiling, electricity is installed. That's the background, and what we would like to create is a laundry room with some storage, and a sauna with a shower (cabin).

I'm just planning and need tips and inspiration, general questions:

1. What is a suitable floor? It's roughly cast concrete on the slab today, and about 2.10 up to the gypsum in the ceiling, so there's not much allowance there. Is tiling the way to go? What would I need underneath and how much space would it take approximately? I think you can manage without underfloor heating since it will be a laundry room, a radiator is easy to install as the boiler is in the other half of the adjoining basement.
2. What are suitable walls? As mentioned, there's gypsum today and there's no moisture problem yet. Is it appropriate to tile everything, or partly and then paint?
3. The new basement's entrance is through the old basement, but I would preferably like to make a staircase down from the living room above. Could this cause any problems?
4. Anything else clever I should think about?

 

[Thomas_Blekinge]

Tiles on the floor are best but will feel cold. Build 12-15 mm. Vinyl flooring feels a bit warmer but requires a leveling layer underneath. I would have preferred tiles plus a cheap textile rug plus slippers.
Walls: Even if you don't see moisture, I think the construction sounds risky. I would have torn down all the plasterboard and OBS. Then smooth plastered and painted. Alternatively tiled.
Entry from the living room? There is a thread here where someone had a basement staircase that ended in the living area and it was so terribly drafty from it that they went completely crazy.

 

[Tvapac]

Tiles on the floor are best but will feel cold. It builds up 12-15 mm. Vinyl flooring feels a little warmer but requires a smoothing layer underneath. I would have preferred tiles plus a cheap textile mat plus slippers.
Walls: Even if you don't see moisture, I think the construction sounds risky. I would have ripped out all the drywall and OSB. Then smoothed plaster and painted. Alternatively, tiled.
Entrance from the living room? There's a thread here where someone had a basement staircase that opened into the living area and it was so incredibly cold from it that they went completely mad.

Thanks for the response. It will probably be tiles on the floor, and some mat or slippers as you say. I don’t find the floor very cold now, I have a fan convector in the basement and keep it around 16 degrees down there. I should be able to continue doing that with a radiator.

Are there always moisture problems with OSB+drywall in a basement? I haven’t checked further than the OSB so I don’t know what it looks like behind, but it’s probably framed with wood. It feels a bit frustrating to tear everything down to plaster, then the electricity and water will end up exposed too. I have felt at the bottom edge of the boards, and it's dry. Can’t I lay tiles on the floor and paint the walls, and then maybe tear more wall coverings later if moisture arises? Or is it also a problem with moisture from washing and sauna from the inside, do you mean?

I haven't even thought about drafts, do they occur if it’s reasonably warm down there, do you think? Maybe I can fit a staircase down that ends with a door; that should work. It might be good from a moisture perspective too if you run a dryer and sauna down there. Ideally, I don’t want to only be able to enter from the old basement; it has a low ceiling and the stairs down there are a death trap if you’ve had a couple of cold ones in the sauna

Speaking of moisture. What ventilation is needed with a sauna and laundry room? Is an exhaust fan like Intellivent, which I have in the bathroom, enough? It uses passive ventilation.

 

[Thomas_Blekinge]

Maybe you are extremely fortunate not to have moisture problems with organic materials in the basement. A future inspector will condemn organic materials there. But if you plan to live there forever, you can take the risk and tile or paint directly on plaster.
It's unfortunate to say, but it's such a typical project where the scope keeps growing. First: "Darling, should we spruce up the laundry room in the basement?"
"Sure! Tiles, and it will look like the brochure."
"Well, the floor needs to be recast, and then you have to replace the floor drain not to lose the insurance. Jackhammering it is!"
"Damn it! What about the walls?"
"Should be torn down. Then there will be new electricity and plumbing. 50 grand extra."
"But you said..."
Sound familiar? With me, it was like that every time.

 

[Tvapac]

That was something neither the seller's nor my inspector commented on when we bought the house. But I understand what you mean. I'll start by removing some plaster and OSB to see what's behind. I'll get back to you with findings from there.

Actually, I see two paths here. Either the basement route where I plaster the walls and keep the entrance from the basement stairs. The other route is to avoid moisture and go with tiles and a staircase down from the living room. But I'm leaning towards the first option, to be honest. Maybe I should spend the money on trying to fix up the old basement and basement stairs so it's easier to access that way.

 

[mannen74]

I have furnished my basement with a laundry room and shower.
There's a staircase down from a hall.
I don't feel any draft from the basement.
I've had geothermal heating for a year now.
I installed an airmove vent in the laundry room and then a vent between the laundry room and the shower. I have installed an Intellivent fan in the bathroom for good ventilation. I have also installed a towel warmer as a heat source in the bathroom. And a regular radiator in the laundry room.
I maintain about 18-20 degrees in the basement.
I also have natural ventilation, but it has decreased due to the removal of the oil furnace.
I have air vents in all rooms.
The bathroom walls are furnished with wooden studs with a moisture barrier underneath. Then OSB + gypsum board. Only moisture barrier in the shower corner walls and floor, then there is only tile on the floor and tiles on the walls.
In the laundry room, I only have tiles on the floor and 2 plastered exterior walls. The interior wall is just painted. I hope it works out, but I will notice in a few years.
There are also metal studs which might be better to use and then only gypsum board walls.

 

[Plupp 161035]

I tore down the ceiling and installed huntonit with LED spotlights. I tore down everything on the wall, the insulation was black in some places. Had paneling and OSB. Wooden studs too. It went quite smoothly, I used Weber's gypsum which I smoothed with a straightedge against a guide that built 0.5cm. Then I took a coarse brush that I dipped in water and added a bit of texture just before it dried. It turned out really nice. Note: it gets wet and mucky so protect well (probably doesn't matter if you're going to tile directly, though).

Then I painted with silicate paint. For the floor, I have Granab steel studs with underfloor ventilation to remove moisture and radon. Then chipboard and single-strip parquet turned out great. If you dig up a couple of centimeters, you can do much more. But ensure the construction too.

I don't believe in shortcuts, but budgeting, setting work hours (I have two small kids), and taking one thing at a time. I've been renovating for two years now, redone the entire rec room, built a sauna, shower, replaced all windows with triple-glazed exterior doors, floors, pretty much the whole house

I'm super satisfied! And I'm on top of the money and not separated

 

[rockin_john]

Does it always lead to moisture problems with OSB+gypsum in a basement? I haven't looked further than the OSB, so I don't know what it looks like behind it, but it's probably framed with wood. .

Wait now! Framed with wood in a basement?
Absolutely NO NO, according to the information I've received. It must be steel studs when it's against concrete....

 

[Manganbangan]

If it is an old house, they have probably nailed studs directly into the concrete, and the studs absorb moisture capillarily depending on the quality of the drainage. I renovated my basement lounge and it was pitch black behind and underneath.

My tip for the floor in the laundry room is a floor with plastic mats like Bergo xl which will lift you up from the cold for a very cheap price.

The walls? Here's what I did! New nice walls in front of the old ones. Completely without contact with moisture.
https://www.byggahus.se/forum/threads/renovera-gillestuga.279231/

 

[Tvapac]

OK! Now I've checked. There were just wooden studs and insulation in the wall against the old cellar. In the three exterior walls, there are Leca-blocks without plaster, steel studs without insulation, OSB, and finally gypsum. Everything feels bone dry.

But many of you recommend removing everything and then plastering, which I think fits quite well in a basement. Is it possible to estimate the cost of plastering three walls of Leca in a room of about 30 sqm? I want to subcontract the plastering and floor tiling.

Right now, I'm considering improving the cellar stairs that exist and tidying up the old cellar area, then laying the same tiles throughout the basement. The new cellar is very roughly cast; it looks level but is coarse and quite uneven. Can tiles be laid with adhesive directly on it, or must it be leveled first?

I have Bergo XL in the old cellar, don't like it, as the floor is so roughly cast underneath. It feels dirty. I would rather have tiles and rugs instead.

 

[zniff]

Your tile installer can probably both plaster the walls and lay tiles with a float underneath for a minimal additional cost. Note that even with good preparation work, it can still fail, which happened to me. The question afterwards was, how do you fix it, alternatively, a monetary discount. It ended up being the latter, but it looks a bit risky. I can recommend shiny granite composite, reflects light very well.

 

[Tvapac]

Your tiler can probably both plaster the walls and lay the tiles with float under for a minimal additional cost. Note that even with good preparation work, it can still fail, which happened to me. The question afterward was, how to fix it, alternatively, a monetary discount. It ended up being the latter, but, it looks a bit tricky. I can recommend glossy granite composite, reflects light very well.

I'll probably do all the preparation work, and then a pro can plaster and set the tiles. I'm terrible at it. Have two drains finished in the rough cast so I would like to have a bit of slope towards these. Then I can grout and finish it myself. That's how it will be!

 

[Evolved]

I am facing the same task and plan to lay raw boards on chipboard flooring, which then float on a Platon mat directly on the concrete floor. Then I create an airflow under the Platon mat by connecting some small pipes to the existing exhaust ventilation along one wall and letting the floor gap a little under the skirting board at the other end of the room so that it can draw in room-temperature air under the floor.
Taadaa! Cold floors no more!

 

[Squall Leonhart]

When it comes to basements, there are clearly two camps:
One camp thinks that it should all be bare concrete everywhere.
The other camp wants to create the same environment as on the ground floor and doesn't care what anyone says.

It's possible to position oneself in the middle. Firstly, there's no general rule for ground conditions throughout Sweden. For example, my house is on a hill with about 6 meters of sand down to the bedrock, my grandfather's home is on moraine where a sturdy excavator is needed to get down, and the house I grew up in is on clay with constant moisture issues. All of this is within Västerbotten.
Secondly, not everyone has the same taste. You can spend money on a livable basement instead of lifting the roof of the house for another floor or extensions. There are evidently rental houses and buildings with businesses that have furnished basements without them being a disaster. So, it’s not impossible to fix it up.

If there were a written law that inspectors would crack down on a furnished basement with wooden studs, any such inspector is welcome to my home. One of the basement rooms is clad with wooden studs and beadboards that I am currently tearing out. There's not even rust on the nails that are in the plugs in the outer walls, and it's been there since 1966.

Common sense can take you far. Do not frame with wood and do not build tightly if the area is prone to moisture, but don't tear down what is problem-free just because there generally should be moisture problems in a basement.

 

[Tvapac]

Makes sense all that you write. If I were to start from scratch, I would go with plaster. But now there are metal studs, drywall, and OSB with electricity and water installed, so it feels a bit wasteful to just tear it all down. Maybe I'll end up tearing it all down anyway, I suppose; ideally, I would like white-painted plaster and tiles.

The ceiling is also drywalled, but I would actually like to have paneling. Damn... it’s going to be tearing everything down, that's what happens when someone else started and you have to take over.