Where is the mold? Smells a lot but can't be seen.

[Back83]

If you have moisture problems, you should definitely look into drainage, but if you're using inorganic materials in the basement, and especially if you're using it as a basement and not living space, the drainage can probably wait a bit (in the past, basements were built as just basements, not as "rooms").

Ventilation in the house is also important to consider for your own health.
New windows: Is it urgent?
If the old ones are not completely rotten, they should last a while longer.
If they are at least double glazed, you can reduce drafts with new seals and let them stay for a while. Of course, it can improve the house's insulation to replace the windows, but there's a lot more that can be done before that (and attic insulation gives even better results than new windows). Additionally, if the windows are in good condition but old, you can install an inner pane (e.g., Grundels does this) to get better insulation at a lower cost and with much less intervention than new windows

Yes, the ventilation is poor, only natural draft, so we installed openable windows as the first thing we did.
We will be using the basement as living space. The bedroom and recreation room will be used daily.

We tore out all the materials and it looked dry and nice. Everything except the particle boards that were directly against the concrete slab. They had propped up the beams with them. It smells much better now. Ran a dehumidifier but not a drop in it after a day running in each room. Could this indicate good drainage?

 

[Totte56]

The particle board... once again, the cause... good that you found the problem.
The drainage?
You need to be able to measure the moisture in the floor and walls... then you can get a better basis for decision?

 

[Back83]

Keep in mind that tiles directly on the slab (which is likely neither insulated nor heated) will be extremely cold. It might be obvious, but since you seem to rely on what others say and then blame them if things don't turn out as you planned, it's best to be excessively clear.

I don't know why replacing the windows is urgent, how much you rely on the basement, or the extent to which the "smell" spreads through the house. However, I would choose to take measures to eliminate the noticeable mold odor indoors and postpone the window replacement a bit, unless there's an urgent reason for it.

If the money isn't enough (or you don't trust contractors), you might need to learn something new and roll up your sleeves.

Tiles do get really cold; I know since we have them in the rest of the basement. I would have preferred it since it would be easier; I'm good at laying them, and above all, they don't absorb moisture from the ground.

We replaced the windows immediately because we want to be able to open them when we light a fire and to ventilate properly in the teenage boy's room. Otherwise, a ventilation hole would have sufficed.

The mold odor disappeared when we tore out the floor. There were particle boards directly on the concrete slab to hold up the joists, so it was those that smelled.

Now the only question is, what floor should we lay?

 

[pacman42]

If it's well-drained, you usually lay down platonmatte - cellplast (XPS, as it is dimensionally stable) for insulation (if needed) - moisture barrier (if you can't make the platon watertight, which is not always possible) - particle board - floor.

That's what I did myself in half of our basement last year after water damage (no construction company had time to do it immediately). I have now ordered a construction company to do it for the rest of the basement this spring (I don't have the time).

 

[Back83]

The chipboard... again, the cause... good that you found the problem.
The drainage?
You must be able to measure the moisture of the floor and walls... then you can probably get a better basis for decision-making?

Yes, it's completely crazy to build up the floor well but then use small chipboards at the bottom.

We ran dehumidifiers for at least 1 day in each room but not a drop, though maybe that’s more due to the dry season than the drainage being good?

Looked at Japegolv but the concrete slab is incredibly uneven so we would first need to self-level so maybe niveled is the best option?
Had a company here yesterday and they install niveled or eps(?) with concrete over it, I think they said. Another construction company is coming today. It feels luxurious to be able to have wooden floors and nice to get rid of bad air, moisture, etc. under the floors, but is it worth it?

 

[Totte56]

I myself have installed underfloor heating in the basement.
First, a Platon mat.
Then 50 mm grooved foam insulation, heat plates, and then water-based underfloor heating.

Then 7.5/mm wooden flooring... not Pergo.
Ventilated baseboard
Now I have the boiler room on the other side of the wall, so it was quite easy to pull the loops through the current wall.

There's a bit of fiddling with the adjacent rooms, like cutting doors and raising thresholds, possibly.

 

[Back83]

If it's well-drained, you usually lay
platon mat - cellplast (XPS, it's dimensionally stable) for insulation (if needed) - moisture barrier (if you can't make the platon tight, which you can't always) - chipboard - floor.

That's what I did myself in half our basement level after a water damage last year (no construction firm had time to do it right away). I have ordered a construction firm to do the rest of the level now in the spring (I don't have time).

Yes, the firms we are supposed to get cost estimates from can't do it until after the holidays, so I would like to fix it myself.
Not a drop in the dehumidifier but maybe that's due to the season? It hasn't been drained since -76.
Big price difference compared to mechanically ventilated floor to do as you did?

 

[pacman42]

Yes, it's completely crazy to build up the floor perfectly but then use small chipboards at the bottom.

We used a dehumidifier for at least 1 day in each room but not a drop, though maybe it rather depends on the dry season than the drainage being good?

Looked at Japegolv but the concrete slab is incredibly uneven so we first need to pour leveling compound, so maybe nivell is the best option?
Had a company here yesterday and they do nivell or eps(?) with concrete over, I think they said. Another construction company is coming today. It feels luxurious to be able to have wooden floors and nice to get rid of bad air, moisture, etc., under the floors, but is it worth it?

Not eps-concrete then (foam pellets in concrete)?

 

[pacman42]

Yes, the firms we are getting cost proposals from can't do anything until after the holidays, so I would prefer to fix it myself.
Not a drop in the dehumidifier, but maybe that's due to the season? It's not been drained since -76.
Is there a big price difference between doing a mechanically ventilated floor and what you did?

My floor cost practically nothing, really. The parquet we laid on top was the most expensive. Platon from Biltema. XPS from Hornbach. Moisture barrier and chipboard from Byggmax. And then parquet flooring on top of that. Check the prices yourself as the thicknesses etc. vary, as do the prices.

Ventilation in the baseboards and you'll have a dry floor as long as the drainage is OK.

Edit: I did two rooms myself in two days (almost, my brother-in-law helped me for a bit, but I would have finished in two days anyway). I didn't even have to take time off from work...

 

[Back83]

I myself have installed underfloor heating in the basement.
First, a Platon membrane.
Then 50 mm grooved polystyrene, heat plates, and then water-based underfloor heating.

Then 7.5 mm wooden floor... not Pergo.
Ventilated floor skirting.
Now, I have the boiler room on the other side of the wall, so it was quite easy to extend the loops through the current wall.

There's a bit of fuss with the adjacent rooms, like sawing off doors and possibly raising thresholds.

It's 15 cm up from the concrete slab, so there would probably be plenty of space, but underfloor heating seems unnecessary in these rooms. Although, with ground-source heating, it might have been worth it. The boiler room is also wall-to-wall with the recreation room 🤔

I would have really liked to have it in the laundry room where the shower is and we have fully tiled. It's not pleasant to set foot without a mat. But it will be a future project.

 

[pacman42]

It's 15cm up from the concrete slab, so there would probably have been plenty of room, but it feels unnecessary to have underfloor heating in these rooms. Although I have geothermal heating, it might have been worth it. The boiler room is also adjacent to the family room 🤔

I really would have liked to have it in the laundry room where the shower is and we have fully tiled. It's not pleasant to put your feet down without a mat. But it will be a future project.

Then install underfloor heating in this room, you lay it on top of the XPS but under the chipboard.

 

[TRJBerg]

Keep in mind that tiling directly on the slab (which is likely neither insulated nor heated) will be extremely cold. This might be obvious, but since you/you seem to rely on what others say and then blame them if everything doesn't turn out as you thought, it's best to be overly explicit.

I don't know why it's urgent to replace the windows, how dependent you are on the basement, or to what extent the "smell" spreads in the house. However, I would choose to take measures to get rid of any noticeable mold smell indoors and postpone the window replacement a bit unless the replacement is urgent for some reason.

If the money isn't enough (or you're not confident in craftsmen) you might need to learn something new and roll up your sleeves.

Quote:
"but since you/you seem to rely on what others say and then blame them if everything doesn't turn out as you thought, it's best to be overly explicit."

Why are you writing things like this? Do you want to start a fight or what?

 

[Back83]

Not eps-concrete then (polystyrene balls in concrete)?

Do you mean eps to level the floor beforehand?

 

[Back83]

My floor basically cost nothing. The parquet we laid on top was the most expensive. Platon from Biltema. XPS from Hornbach. Moisture barrier and chipboard from Byggmax. And then parquet flooring on top. Check the prices yourself as thicknesses, etc., vary, as do prices.

Ventilation in the floor mouldings and you have a dry floor as long as the drainage is OK.

Edit: I did two rooms myself in two days (almost, my brother-in-law helped me for a bit, but I would have finished in two days anyway). I didn't even have to take time off from work...

Doesn't it need to be quite flat before laying platon? It's very uneven so at least 5 cm to level the floor first.

 

[pacman42]

Doesn't it need to be quite even before laying platon? It's very uneven, so at least 5 cm to level the floor beforehand.

5CM is maybe a bit too much. Time for some self-leveling compound then. However, it doesn't need to be completely smooth. An amateur can manage it...