I am currently working on drainage. The house is from 1946 and there was no drainage previously. The basement walls are about 160 cm below the ground surface.
The basement walls are quite bad, sporadically very bad with large areas of flaking plaster covering various damage over time, especially moisture damage. Now, remediation of the basement walls is necessary.
What is the best way and method to solve such a classic problem? That is the basis of my question and I would be very grateful for experiences and advice from others who have dealt with similar issues.
Some specific questions regarding this problem:
- Which medium, plaster mortar, or similar is best to use for remediation of such old basement walls?
- For example: Mur & Putsbruk C; Mur & Putsbruk B (0-3 mm or 0-1 mm); Cementbruk A? What experiences and recommendations are there for using, for instance, Nivoplan, Sika products (Sika Montop 650 or Sika Top seal 107), Weber 135, etc.?
- What are the main details and guidelines when conducting remediation – plastering of this type of basement wall? Preparatory work, which surfaces to treat at a time, what coating. Is a fixer or cement mixing base recommended for better adhesion of the plaster?
The basement walls are quite bad, sporadically very bad with large areas of flaking plaster covering various damage over time, especially moisture damage. Now, remediation of the basement walls is necessary.
What is the best way and method to solve such a classic problem? That is the basis of my question and I would be very grateful for experiences and advice from others who have dealt with similar issues.
Some specific questions regarding this problem:
- Which medium, plaster mortar, or similar is best to use for remediation of such old basement walls?
- For example: Mur & Putsbruk C; Mur & Putsbruk B (0-3 mm or 0-1 mm); Cementbruk A? What experiences and recommendations are there for using, for instance, Nivoplan, Sika products (Sika Montop 650 or Sika Top seal 107), Weber 135, etc.?
- What are the main details and guidelines when conducting remediation – plastering of this type of basement wall? Preparatory work, which surfaces to treat at a time, what coating. Is a fixer or cement mixing base recommended for better adhesion of the plaster?
Member
· Västernorrland
· 12 030 posts
I would probably drain and then let it sit for a while and then in a few years address the basement. There are excellent primers for such work that allow normal plaster to adhere, so that's probably the least of the problems. Step one is still probably first to address the moisture and then make sure it really stays dry afterwards.
Thank you, Stefan!
I appreciate your reasoning, and you are probably completely right. One should first look at the effect of drainage, wait for the wall to dry, and then address it. But I have a small problem with waiting, at least in a small part. Namely, I want to install some radiators and heat the basement, which should generally improve the health of the basement-house. So I need to at least repair – plaster the area of the wall where the radiators (waterborne heating system) will be. I can do it spot by spot, and the main question is: which mortar and plaster is best to use: Masonry & Plastering B (0-3 mm / 0-1 mm), Plastering C, or Plaster and Masonry C... or?
Best regards, Mika
I appreciate your reasoning, and you are probably completely right. One should first look at the effect of drainage, wait for the wall to dry, and then address it. But I have a small problem with waiting, at least in a small part. Namely, I want to install some radiators and heat the basement, which should generally improve the health of the basement-house. So I need to at least repair – plaster the area of the wall where the radiators (waterborne heating system) will be. I can do it spot by spot, and the main question is: which mortar and plaster is best to use: Masonry & Plastering B (0-3 mm / 0-1 mm), Plastering C, or Plaster and Masonry C... or?
Best regards, Mika
There are often two sides when this question arises. I believe that a basement wall with the right paint can perform very well even if it's humid. So if you remove the loose pieces and the paint that is there now, then paint with silicate paint, it will be fine even with inadequate drainage. I mean there are plastered outdoor walls that remain nice year after year.
I had a similar problem. I was advised to use the same type of plaster or a weaker one than what was already there when I repaired it. I knocked off what was loose and then repaired those surfaces. Then I painted everything with silicate paint. The plaster and paint are holding up well a year later. Had I done this today, I would have chosen to scrape off all the old plaster and replace it with new ones. I believe you get a more even wall if you replaster the entire surface since it is very difficult to get it even when repairing. You are also freer to use any type of plaster since it won't risk reacting badly with the existing plaster.
Regarding moisture in the basement, a little moisture is not a problem unless you enclose it or have organic materials against it that can start to mold. But what is considered "a little moisture" and when it becomes necessary to drain is difficult to define clearly. If you find it very damp and it smells of mold, it might be time to drain.
Regarding moisture in the basement, a little moisture is not a problem unless you enclose it or have organic materials against it that can start to mold. But what is considered "a little moisture" and when it becomes necessary to drain is difficult to define clearly. If you find it very damp and it smells of mold, it might be time to drain.
Given the year, the basement is likely plastered with lime mortar. In that case, stick to lime mortar unless you are replastering completely. This would also explain why you have such significant plaster damage; lime mortar does not like moisture. In the 1950s, the product Gullex was introduced to the market, and thus cement lime mortars eventually took over. But your house is older.
You can easily solve moisture issues with a dehumidifier in the summer and fall. During the winter, you can heat the basement to keep it dry.
You can easily solve moisture issues with a dehumidifier in the summer and fall. During the winter, you can heat the basement to keep it dry.