How do you fix high humidity levels in a basement?
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How do you fix high humidity levels in a basement?
Good morning,
I bought an older house (built 1965) in September 2018 and shortly after moving in (mid October), I was experiencing extreme joint pains. Strangely, I was feeling pain and discomfort only inside my house, everywhere else I was perfectly fine. One year later, the moldy batt insulation in the basement has been removed and replaced with spray foam insulation; the foundation around my house on the outside surface has been waterproofed (4 cracks were found inside the basement walls) and the grading reversed. I’ve had many contractors come to my house and most of their suggestions have been implemented. Unfortunately, $40k later, the humidity inside my home is still high 50-65% .
Furthermore, a contractor recommended installing an air purifying system, adding additional insulation in the attic and refinishing the walls in the basement to reduce humidity and coldness in my home. Frankly, I am not sure whom to trust anymore, therefore, your guidance would be greatly appreciated.
JR Tadinac
You were wise to remove the moldy insulation and re-insulate, as well as taking steps to mitigate water infiltration into the basement. A house that old would not have any vapor barrier below the concrete floor, so even if you did insulate and seal the walls with aspray foam vapor barrier, it will likely continue to absorb moisture from the ground below and release it into the home. And if it is not insulated, it will of course feel cold as well.
I think the next logical step is for you to put a dehumidifier in the basement. 50 – 65 RH is a little bit high, but with a dehumidifier that you could buy for a couple of hundred dollars I think you could bring it down quite a bit and maybe solve your problems.Due to the natural stack effect, humid air from the basement will rise to the living area所以解决楼下的问题，你就可以在楼上解决。If you do plan to do further work, we can certainly help you choose the best course of action and if so, here are a few questions we would have if you want to work on it further –
Is the basement floor finished?
是用作居住空间吗?
How much ceiling height do you have?
Is there a sump pump?
Is there any signs of flooding?
感谢您花时间阅读和回复我的帖子。地下室楼层/区域没有完成，也没有用作生活空间。从地板到地板托梁底部的高度是84英寸。没有水池水泵，我不确定在我搬进房子之前是否有洪水。然而，房屋检查员指出，在某些区域的墙壁底部有风化痕迹。
有一次，我想在地下室的地板托梁上安装roxul绝缘材料，但我的想法被否决了。我被告知我应该在阁楼加一些绝缘材料，并在地下室的墙壁上加一些绝缘材料。我需要做更多的工作，我的目标是让房子冬天温暖，夏天不潮湿。非常感谢您的建议!
JR Tadinac
Attic insulation is a good idea, but uninsulated basements are a heat sink, so best is to make sure they are both done. The only reason to insulate the joists above your head in the basement is if you plan to keep the basement at a cooler temperature. If so, then it will work, but with pros and cons however - it's cheaper, faster and easier, but it doesn't do anything to prevent moisture infiltration through the pourous concrete floor. And if you heat the basement then it doesn't serve much purpose at all.
或者，你也可以把地下室当作家里空调空间的一部分，把地板和墙壁都隔离起来。Here is a page that may be helpful abouthow to insulate a basement floor properly. That would help a lot with reducing your heating demand, it would also prevent moisture from continually being absorbed from the ground and being added to the humidity of your home. The reason I asked about head room and how you use the basement is to see if insulating the floor is even an option. if it's 7 feet high now, you could raise it up 4-6 inches and only the tallest of your tall friends will bonk their heads.
As for a sump pump, I have never heard anyone say they 'regretted' putting one in. It's easy and relatively cheap considering the nightmare situations that it may prevent. I would do it, especially if you plan to insulate the floor.