I don't think it's the humidity that's the main culprit (if it was, the walls would erode here and there, not just at the bottom near the floor), but rather that the wall is absorbing moisture from the ground underneath. This is very common. Whether the moisture in the ground comes from a broken pipe or is just regular groundwater keeping the soil moist is hard to say.
That the thin walls are the worst affected could be because they might be made of a different (more absorbent) material than the thick ones?
That the thin walls are the worst affected could be because they might be made of a different (more absorbent) material than the thick ones?
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The narrow walls are probably concrete elements then, I scraped and there was a fairly thick layer of plaster, and under the plaster, there appeared vertical gaps/spaces about 40cm apart.
Is there another way to find out where the moisture is coming from? Like some camera/meter that can compare humidity near sewage pipes and exterior walls.
We have just bought the house (turn of the year), can we get any financial support to address this? The inspection report did not mention anything about moisture in the slab or basement walls.
Is there another way to find out where the moisture is coming from? Like some camera/meter that can compare humidity near sewage pipes and exterior walls.
We have just bought the house (turn of the year), can we get any financial support to address this? The inspection report did not mention anything about moisture in the slab or basement walls.
I think it looks like lightweight concrete blocks. Scrape a few decimeters up as well and you'll see that you also find horizontal gaps. That is, it is built with blocks.fulingbusen said:
Yes, there are such moisture meters available for purchase/rent. However, one should have some knowledge of where and why to measure. You could perhaps call in an inspector to conduct a small investigation if you feel uncertain? Inspectors usually are equipped with moisture meters.fulingbusen said:
I doubt you can get any financial support for this, unless you have generous parents or the like?fulingbusen said:
However, I guess you're referring to claiming this as a "hidden defect"? That's probably wishful thinking, unfortunately...
Moisture in basements and slabs is very common in older houses. If the technical life span of the drainage is also passed (which it seems to be) this is something to be expected. The moisture in the walls probably could have been measured too (if you had done it).
But moisture in basements does not necessarily have to be a big problem. As long as you don't have lots of organic material where the moisture is present, it won't start to mold.
The moisture rising in the walls could be due to several factors. Is the paint on the floors diffusion-tight? Then maybe the moisture seeks into the adjacent walls instead of being vented up through the slab (floor). In that case, remove the paint and apply tiles or another material that allows the moisture to pass through.
It might be sufficient to replaster the walls and apply some breathable silicate paint.
But it could also be a sign that it's indeed time to redo the drainage?
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It is an old house (moved to a basement foundation) and there are plans to both replace cast iron pipes and drain the house, but unfortunately, there are also a hundred other things to take care of. You start to understand those who warned that an old house is an endless project 
I have no idea about the color of the floors, the color that exists has probably been there for a while, and much of it is already worn off.
I have called a company that I hope can come and determine if it's the drains that are bad or not www.söderlundhs.se
I'm going to keep scraping the thin wall just for fun
But I'm also thinking about the slab, what is a common thickness from the 50s-60s? Can it be so thin that all the moisture comes from underneath? Is it stupid to drill a hole to see how thick it is? Are there other ways to see the thickness than drilling a hole?
If I now have to break up the floor in the basement to replace drainage pipes, maybe it's just as well to pour a thicker slab and insulate for future heating of the basement.
I have no idea about the color of the floors, the color that exists has probably been there for a while, and much of it is already worn off.
I have called a company that I hope can come and determine if it's the drains that are bad or not www.söderlundhs.se
I'm going to keep scraping the thin wall just for fun
But I'm also thinking about the slab, what is a common thickness from the 50s-60s? Can it be so thin that all the moisture comes from underneath? Is it stupid to drill a hole to see how thick it is? Are there other ways to see the thickness than drilling a hole?
If I now have to break up the floor in the basement to replace drainage pipes, maybe it's just as well to pour a thicker slab and insulate for future heating of the basement.
I think you should assume there is moisture in the slab when it comes to a house from the 50s. However, it doesn't necessarily mean any problems automatically, as long as the moisture can be ventilated away.fulingbusen said:
Replacing the cast iron drain and at the same time taking the opportunity to tear up the entire slab and then cast a new one, is a bit like saying: I was thinking of replacing the fan belt on the car, but then I thought it might be just as well to remove the entire engine and install a brand new engine instead.
You'll certainly have less moisture and be able to run waterborne floor heating with a new insulated slab. But it will probably cost quite a lot to subcontract. If you do it yourself, it will be cheaper, but prepare for hard work.
I would probably spend the money on new drainage and insulation of the basement walls (from the outside).
Regarding the plaster release, it doesn't necessarily have to be the moisture in the floor that is the actual problem. Of course, the moisture comes from there, but by having a paint that breathes, the moisture is ventilated away. It's when the moisture is trapped in the wall material that plaster/paint peeling occurs.
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Agree with eviljava. If you don't plan to convert the basement spaces into living areas and still only have storage, laundry room, boiler room, workshop, etc. down there, you don't really need to break up the entire slab and pour a new one.
Sure, it's probably a bit raw and damp environment, but that's not a problem as long as you only build with inorganic materials in the basement and don't trap moisture behind tight paint, allowing floors and walls to breathe.
Sure, it's probably a bit raw and damp environment, but that's not a problem as long as you only build with inorganic materials in the basement and don't trap moisture behind tight paint, allowing floors and walls to breathe.
Okay, thanks a lot for all the answers.
The plan in my head now is to first get help from someone who can check if the drain pipes are leaking. If they don't see any leakage, I will try to remove old paint and replace it with silicate paint and then, in the future, fill in the well in the old "garage" and replace everything in cast iron (pipes and wells), drain and add insulation to walls (isodrän/pordrän). If we want to live in the basement, we'll go with plastered walls and that kind of low-profile insulating floor heating (pre-made panels). Does that sound reasonable?
I've plugged the vents in the basement now and plan to keep them closed as long as I'm using the dehumidifier. Is it okay to have them closed year-round as long as the air isn't stagnant and the humidity doesn't exceed 70% (the dehumidifier is set to 65%) Mitsubishi EVX2 or whatever it's called?
The plan in my head now is to first get help from someone who can check if the drain pipes are leaking. If they don't see any leakage, I will try to remove old paint and replace it with silicate paint and then, in the future, fill in the well in the old "garage" and replace everything in cast iron (pipes and wells), drain and add insulation to walls (isodrän/pordrän). If we want to live in the basement, we'll go with plastered walls and that kind of low-profile insulating floor heating (pre-made panels). Does that sound reasonable?
I've plugged the vents in the basement now and plan to keep them closed as long as I'm using the dehumidifier. Is it okay to have them closed year-round as long as the air isn't stagnant and the humidity doesn't exceed 70% (the dehumidifier is set to 65%) Mitsubishi EVX2 or whatever it's called?
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Yes, it sounds sensible.fulingbusen said:
Hmmm... you need to get fresh air somewhere. It might be possible to close them when it's most humid (July, Aug, Sept), but then they should probably be opened. But on the other hand, there's hardly any draft at all in the vents during summer (in passive ventilation houses).fulingbusen said:
I'm assuming from my own house (passive ventilation) and all the fresh air vents are in the basement and the exhaust vents (except the range hood) are on the upper floor. This creates an even draft throughout the house, and the air coming in is "preheated" in the basement and therefore not ice-cold when it reaches the living area. If I were to close my vents in the basement, I would likely have significantly worse ventilation throughout the house.
Very good. While he's at it, you can ask him to draw the sewage layout on the blueprint you have. It's good to know where these go. At the same time, you can ask him if this sewage is "for itself" or if it is connected to the rest of the house. If it turns out to be a leak, ask him how he sees the possibility of sealing the pipes with a liner, and if he has any tips on who can do this.fulingbusen said:
I would say that removing old paint and drainage are on the same priority level, i.e., no.1. Then you may need to replaster certain walls? Painting isn't necessarily something you need to do immediately, and the plaster should be dry when you do this.fulingbusen said:
I thought of something in connection with this. Is the basement cold, or unevenly warm? If so, it functions like a classic vented crawl space, i.e., it becomes very humid in the areas that are cold. If that's the case, you should have the vents closed, and then try to arrange for a more even heat distribution.fulingbusen said:
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This is starting to become a general thread about my house (which is very okay with me)
The house is a stick-built house (is that what it's called?), thin timber with a wood facade.
I use the stove a lot in the winter and have a bathroom fan, aside from that, it has natural ventilation. Openings/dampers at the top of all windows that are always open, ventilation grilles in the basement and pantry. The basement is unheated during winter and closed off, but I have an old patio door leading to the garage that lets in a draft (unintentionally). Last winter, there was a lot of draft coming from the basement up into the house/hallway through gaps in the stairs, which I have now sealed with latex caulk. I assume there's still some draft through the basement door and stairs but hadn't considered that this is good. I've even thought about insulating the stairs since the electric bill in winter isn't fun with the combi boiler running on electricity. During the summer, I've supplemented with a heat pump and stocked up 5 cubic meters of firewood for the stove.
The house is a stick-built house (is that what it's called?), thin timber with a wood facade.
I use the stove a lot in the winter and have a bathroom fan, aside from that, it has natural ventilation. Openings/dampers at the top of all windows that are always open, ventilation grilles in the basement and pantry. The basement is unheated during winter and closed off, but I have an old patio door leading to the garage that lets in a draft (unintentionally). Last winter, there was a lot of draft coming from the basement up into the house/hallway through gaps in the stairs, which I have now sealed with latex caulk. I assume there's still some draft through the basement door and stairs but hadn't considered that this is good. I've even thought about insulating the stairs since the electric bill in winter isn't fun with the combi boiler running on electricity. During the summer, I've supplemented with a heat pump and stocked up 5 cubic meters of firewood for the stove.
I managed to post the above before I read Raceman's post.
Good tip about including the sewage pipes in the drawing, I'll remember that.
With a newborn, a 3.5-year-old, and various trips and work involved, I won't have time to drain before winter. But I'll try to do this in the spring and try to fix the surface of the basement walls during the winter.
It's an unheated basement, the panann is down there, and some radiators leak a bit via the thermostat, but maybe it will be +5 degrees in January. I'd like to move towards heating it up once I've drained and made the basement more livable.
Good tip about including the sewage pipes in the drawing, I'll remember that.
With a newborn, a 3.5-year-old, and various trips and work involved, I won't have time to drain before winter. But I'll try to do this in the spring and try to fix the surface of the basement walls during the winter.
It's an unheated basement, the panann is down there, and some radiators leak a bit via the thermostat, but maybe it will be +5 degrees in January. I'd like to move towards heating it up once I've drained and made the basement more livable.
If it is as you say, I would argue that the likelihood is great that the temperature goes towards, or even below 0 on some cold winter nights. When this happens, the damp concrete gets frost-shattered/weathers. If the basement is much colder than the surroundings even in the summer (and you have ordinary "vent valve ventilation") then it is precisely during that time of the year that the basement becomes the most humid.fulingbusen said:
I have acquired a weather station to keep track of the temperature now in winter. The only reference I have from last winter is that the clothes dried nicely and I managed to hang laundry in my underwear without freezing
I think it's now after the high summer that the walls have weathered more.
But if I keep +5 at waist height at least this winter and run the dehumidifier (if it starts in the winter?) so the air circulates. Is that "ventilation" sufficient for the basement, and does the living space upstairs get air from the window vents?
I think it's now after the high summer that the walls have weathered more.
But if I keep +5 at waist height at least this winter and run the dehumidifier (if it starts in the winter?) so the air circulates. Is that "ventilation" sufficient for the basement, and does the living space upstairs get air from the window vents?
Lifting the thread and jumping back a bit. The walls are still in the same condition and now we're thinking of turning the old garage into an extra room for guests or a playroom for the kids.
Since the render seems porous, it looks like we should use lime render. Thinking of washing the walls with a pressure washer to clean them, remove anything loose, and soak them so the new render adheres. Should I also scrape off or roughen the surface around the areas I plan to improve?
Since the render seems porous, it looks like we should use lime render. Thinking of washing the walls with a pressure washer to clean them, remove anything loose, and soak them so the new render adheres. Should I also scrape off or roughen the surface around the areas I plan to improve?
I think it sounds a bit extreme to bring out a pressure washer to remove loose plaster. Where will all the water go?
Even if you have a floor drain in the room, a lot of plaster/sand will follow. This is probably not something you want in the drainage?
It gets messy enough even if you do it the conventional way.
Personally, I would take a hammer and chisel and simply knock down everything loose. Then I would wet it and plaster in the usual way, just before the plaster is applied.
Even if you have a floor drain in the room, a lot of plaster/sand will follow. This is probably not something you want in the drainage?
It gets messy enough even if you do it the conventional way.
Personally, I would take a hammer and chisel and simply knock down everything loose. Then I would wet it and plaster in the usual way, just before the plaster is applied.