My basement was really damp... Redrained with Isodrän, dried out with a dehumidifier for about 4 months, framed with steel and plasterboard on the walls, tiled the floor, added one supply vent per 25 sqm, supplemented with radiators to keep the humidity down. It smells wonderful and feels really nice in the basement now.
However, the supply vents cooled down the floor above quite a lot as the cold air went straight up into the framing (I think it's called the "trossbotten").
However, the supply vents cooled down the floor above quite a lot as the cold air went straight up into the framing (I think it's called the "trossbotten").
Ahoy, all basement renovators! Thought I'd share some of my experiences. Discovered a water leak in the basement wall... Ouch, ouch... Couldn't fix it from the outside due to a slope foundation. The solution was to inject the leak. It was left open for a year (!) to check that it held tight in all seasons. And it did! Still wanted to secure the future, so we invested in a mechanically ventilated floor. I can warmly recommend Fuktspärrteknik AB, by the way. Very serious company that really thought it through before presenting a solution. We came up with a solution where we ventilate both the floor and the wall that leaked, just to be safe. A fan on the outside of the house sucks air from the room through intakes at strategic points on the walls. On top of the moisture barrier we put polystyrene, chipboard, and parquet. For the walls, we used metal studs, insulation (with an air gap between the concrete and insulation), OSB boards and drywall. The walls were painted. Everything was great until the cold came. (We fixed up the basement about a year ago.) I think the cracks are due to the OSB boards under the drywall moving with temperature differences. However, it's not worse than I think it can be fixed by putting up fabric or wallpaper instead of painting directly on the drywall. Haven't had the energy to address it yet, and don't know if I will, since the kids use the room as a crash-and-bang room...
We face similar questions as many others - what should be done with the outer walls in the basement?
We live in a 1920s house that is semi-basement, meaning half of the basement is above ground and half is dug down about half a meter. We are now going to dig out the basement, insulate, install hydronic underfloor heating and then build a bathroom. That's where the questions begin!
1) Our basement walls are insulated from the inside with mineral wool boards and then plastered and painted with silicate paint. There are no signs of mold, and it doesn't smell like a basement. However, we know that moisture travels in the walls because we haven't drained the house. What should we do if we want to place a bathtub against such an outer wall? We planned to build a "half-wall" that doesn't go completely up to the ceiling right by the bathtub. But can you frame up against the outer wall and install a wet room board and then have vents on the sides, or is that creating problems?
2) Should the entire floor be waterproofed, or should you only waterproof around the shower and drain? The room is 14 square meters.
Grateful for advice!
We live in a 1920s house that is semi-basement, meaning half of the basement is above ground and half is dug down about half a meter. We are now going to dig out the basement, insulate, install hydronic underfloor heating and then build a bathroom. That's where the questions begin!
1) Our basement walls are insulated from the inside with mineral wool boards and then plastered and painted with silicate paint. There are no signs of mold, and it doesn't smell like a basement. However, we know that moisture travels in the walls because we haven't drained the house. What should we do if we want to place a bathtub against such an outer wall? We planned to build a "half-wall" that doesn't go completely up to the ceiling right by the bathtub. But can you frame up against the outer wall and install a wet room board and then have vents on the sides, or is that creating problems?
2) Should the entire floor be waterproofed, or should you only waterproof around the shower and drain? The room is 14 square meters.
Grateful for advice!
I am also considering the issue of drywall in the basement. Currently, I have a basement that doesn't have any moisture problems. There are wood wool panels on the walls, followed by wooden studs and wood paneling. I really dislike the paneling and want to remove it and install drywall instead. The plan is to simultaneously switch to steel studs.
The question is whether I need to do anything other than just replacing the wooden studs with steel and the wood paneling with drywall. From what I understand, the wood wool panels should breathe well enough—does this mean nothing more needs to be done behind the drywall? It would also be nice to add some extra insulation in the walls, and I would appreciate it if someone could give me some tips.
I'm including a section and a floor plan of the room (it's the circled room in question). It might not be very clear in the pictures since they couldn't be that large. It's at least 70mm wood wool panels attached to a 200mm concrete wall, and outside of this, there's 25mm asphalt board if I understood everything correctly.
The question is whether I need to do anything other than just replacing the wooden studs with steel and the wood paneling with drywall. From what I understand, the wood wool panels should breathe well enough—does this mean nothing more needs to be done behind the drywall? It would also be nice to add some extra insulation in the walls, and I would appreciate it if someone could give me some tips.
I'm including a section and a floor plan of the room (it's the circled room in question). It might not be very clear in the pictures since they couldn't be that large. It's at least 70mm wood wool panels attached to a 200mm concrete wall, and outside of this, there's 25mm asphalt board if I understood everything correctly.
You write nothing about how the issue of moisture transport on the outside is solved. That is, drainage and insulation.
It is absolutely crucial for how things work on the inside.
If there is correctly placed insulation from the outside and a good drainage system placed below the foundation level along the house, the situation is entirely different than if you have only fixed things on the inside.
If the drainage, etc., doesn't work, it almost doesn't matter what you do on the inside, moisture will creep in and cause damage.
It is absolutely crucial for how things work on the inside.
If there is correctly placed insulation from the outside and a good drainage system placed below the foundation level along the house, the situation is entirely different than if you have only fixed things on the inside.
If the drainage, etc., doesn't work, it almost doesn't matter what you do on the inside, moisture will creep in and cause damage.
I tore everything out, both above and below ground. Smooth plastered walls throughout the basement. Painted white with silicate. Fresh and neat. The lightweight concrete (siporex) already has a fairly OK insulation value. If needed, I'll insulate from the outside at a later stage.
You can space the OSB boards behind the drywall with three to five mm, so they have some room for movement. If they are flush against each other, they can't swell without cracking. Could potentially help with the cracking issues.seclest said:
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you forgot the air gap and ventilation behind the stud wall.Nimajneb said:
isoskiva you can certainly have.
metal studs are a given.
most important of all is to make sure you have good drainage and podränskiva.
regards
estwing
I have an even better variant that I've tried with good results: if the walls are already plastered and smooth, it's excellent to use regular multifix to attach Styrofoam to the wall, then an aquaboard or minerit.
I apply vertical strips at c-c 60 cm or c-c 45 cm, press the Styrofoam there, then the board which also gets strips with the fix.
Then I nail the board with 4-6 hammer nails, just as a fixation until it dries.
Then I fill the joints with fix, around the windows I also use the aquaboard/minerit as trim.
The result is a wall that can be painted, wallpapered, or tiled.
Completely moisture, mold, and rust-free.
The downsides are the price for the aquaboard and that the wall can be difficult to attach things to without really long screws.
If you're used to masonry work or tiling, this is easy and quick.
I apply vertical strips at c-c 60 cm or c-c 45 cm, press the Styrofoam there, then the board which also gets strips with the fix.
Then I nail the board with 4-6 hammer nails, just as a fixation until it dries.
Then I fill the joints with fix, around the windows I also use the aquaboard/minerit as trim.
The result is a wall that can be painted, wallpapered, or tiled.
Completely moisture, mold, and rust-free.
The downsides are the price for the aquaboard and that the wall can be difficult to attach things to without really long screws.
If you're used to masonry work or tiling, this is easy and quick.
Interesting discussion.
Our basement has an uninsulated slab, so I want to lay 20-30 mm of foam plastic on it to reduce cold penetration. On top, I'm planning to use click vinyl flooring to completely avoid organic materials.
The foam plastic is capillary breaking, so I'm wondering if I can lay it directly on the slab?
Or is platon or construction plastic recommended first?
[the slab is on a gravel bed and the external walls have external platon and ground insulation]
Our basement has an uninsulated slab, so I want to lay 20-30 mm of foam plastic on it to reduce cold penetration. On top, I'm planning to use click vinyl flooring to completely avoid organic materials.
The foam plastic is capillary breaking, so I'm wondering if I can lay it directly on the slab?
Or is platon or construction plastic recommended first?
[the slab is on a gravel bed and the external walls have external platon and ground insulation]
The question is whether you need to care? The styrofoam and vinyl flooring resist any moisture. Building plastic should be installed where warm meets cold but normally not on the floor. Warm air rises, so building plastic is most beneficial in the ceiling, then in the outer wall.
On the floor, it is least beneficial.
Go ahead, if you're afraid of mold smell it's more important that the slab is completely clean from particles that CAN mold together with moisture.
On the floor, it is least beneficial.
Go ahead, if you're afraid of mold smell it's more important that the slab is completely clean from particles that CAN mold together with moisture.