What’s subsequent? Feeling misplaced with humid basement (NC, US).
Hello all,
My spouse and I just lately grew to become householders and we’re dealing with a humidity/mildew situation in our basement. Fortuitously, there is no wooden rot but, however we have now observed some mildew progress and uncontrolled humidity.
Our basement is unfinished, with filth flooring and open concrete partitions on the facet of a hill. Here is the present state ([https://imgur.com/a/THYfqUQ](https://imgur.com/a/THYfqUQ)):
* The vents are closed and we’re working a dehumidifier
* Spray foamed rim joists
* The insulation below the primary ground is outdated and falling aside
* The froth boards on the partitions are additionally outdated and falling aside
Humidity ranges stay persistently excessive, starting from the 60s to 70s and even 80s on the dangerous days. We’re feeling a bit overwhelmed and uncertain of the following steps. Ought to we think about placing foam boards on the partitions? In that case, does each inch must be lined to assist? Is it mandatory to switch or take away the insulation? There’s a window within the basement, am I suppose to seal that? Would it not be useful to spend money on a moisture barrier?
Any steerage or recommendation any of you’ll be able to present could be tremendously appreciated.
Comments ( 15 )
Not sure what “open concrete walls” mean, but google *crawl space encapsulation* . It’s basically putting in a drainage system and sump pump (if needed), closing off all outside ventilation and then lining the floors and walls with heavy duty vinyl sheeting. If it applies to your house, you can buy the materials and do it yourself. I did my small house about 7 years ago using used billboard tarps and it cost hardly anything and has worked fine. Usually a dehumidifier is also called for, but I skipped that also.
The dirt floor is the problem. I’m not an expert but until one shows up, I suggest looking into radon mitigation for ideas on how to properly seal the floor. Something like this https://radoncorp.com/radon-block
I don’t think trapping moisture on the inside of your basement walls (between the wall and the foam board) is a good idea at all. In my experience, the only way to treat a basement for water issues successfully is to put the barrier on the outside of the house all the way down to the bottom of the foundation. I did this to my house and have not had any issues since.
We dug a trench on the outside of the house right up against the cinder block foundation walls. We added a double barrier made out of rigid plastic that sticks up about 1’ from the ground and goes all the way to the bottom of the foundation. There is no realistic way for water to get in between the barrier and my foundation wall when it rains. At the bottom of the foundation is also a layer of gravel and some PVC pipes that help route the groundwater away from my house. My unfinished basement walls used to ‘weep” whenever it rained and were constantly damp. During heavy rain, we would even get puddles. After we treated it, the entire room was bone dry for over a year. We eventually finished the space and have had no issues in over 5 years now.
Before we got serious about it we tried everything – patching the walls, putting down waterproof sealants, etc. Nothing worked – water always finds a way in unless you make it impossible.
You also need a floor and I’m guessing that is a huge issue as well. Whatever you do you are going to need to hire someone who specializes in this.
Not an infinite expert, but the dirt floor is the problem. Ground moisture just directly seeps through the floor. The walls you could apply Drylok to repel water passing through the walls, but I think a concrete floor is your only hope to dry the space out. The magic number is 55%, if you get the humidity below that point then mold won’t grow. A high quality, high capacity dehumidifier is key. If you are needing to manually dump it I don’t think you are maximizing the device. If it drains into the dirt floor you’re not really drying the area out.
My dehumidifier drains directly into a drain and can draw 80 pints from the air per day in my stone foundation basement. I’m about to reapply Drylok to the walls and apply a coat to the floor after sealing all floor cracks. I consider my dehumidifier appropriate for my basement, I imagine you need to step it up in your basement.
Do you have a dehumidifier? We have 2 in our basement.
I will admit that my basement experience is somewhat limited, but “closed the vents”?
What vents? Vents to HVAC from above? Vents from the basement to outside? It would seem to me that any kind of air circulation would be beneficial.
I also agree with u/javeryh who talks about keeping moisture out, rather than trapping it in.
I looked at the basement encapsulation once (when I had a basement in the midwest) and it just looked pretty. Who wouldn’t want a nice, clean, plastic lining rather than the (to me)creepy, scary, dirty dirt basement thing…but what does it really solve???
At the end of the day, you need to keep the moisture OUT of the basement, not just under a layer of plastic.
I wrapped a dirt floor crawl space in a building I remodeled last summer. It worked really well. Looked really nice, and you could instantly feel the difference in the humidity. These are the products that we used, https://www.stegoindustries.com/products . I was very satisfied with them.
This is a franchise that specializes in wet basements and they know their shit.
https://www.basementsystems.com
It’s a DIY sub so I’m not saying you have to use them but their methodology is sound. Read their materials to get some ideas of how to approach your problem.
https://www.basementsystems.com/basement-waterproofing/basement-learning-center/dry-basement-science.html
You have a crawlspace, not a basement. Knowing the difference will help you find the right solution.
Your best bet is to encapsulate or seal the crawl space . If you have the budget just pay somebody to do it. There are usually local companies that do this work . You can add sunp , pumps, or french drains depending on the need .
All comments so far basically suck.
Buy enough 6 Mil polyurethane plastic to cover the dirt and cover the dirt with it.
If that doesn’t substantially change things (it will), then add 1″ extruded polystyrene to the inside of the concrete.
The polyurethane alone will change everything.
Our house has a crawl space and our land is ridiculously wet (as in so wet we have to keep our yard covered in wood chips or you’ll just sink into the ground… when we bought the house it was grass and our dogs turned it into mud instantly just by running around on it). The floor of crawl space is completely covered in a plastic moisture barrier and the foundation is sprayed on the inside. We have a dehumidifier running and it’s bone dry. So it’s probably the floor.
I think you major problem is the exposed dirt. Especially here in NC (also a resident) there is a LOT of moisture that comes up from the ground. pretty much every house on a crawl space should have something to stand between ground moisture and the floor joists. One of the first things I did in my crawl space was lay a new VB. [Something like this will do just fine](https://www.homedepot.com/p/MP-Global-Products-100-sq-ft-Rolls-30-x-in-W-x-40-x-ft-L-x-6-mm-T-Polyethylene-Film-Moisture-Vapor-Barrier-Underlayment-for-All-Floors-MB006300100/100641164). Just do the math to get enough for you to allow it to ride up the block walls about 2-3 inches on all sides and overlap about the same. You do not need to tape it. Cut slits to get around footings and what not. Between this and a good dehumidifier you’ll be shocked at the air quality change.
Once you get that done you might need to look at the insulation. If it’s been existing in 70+% humidity for a while it might take an eternity to dry out. If the time/effort and cost aren’t a major roadblock consider replacing it **if needed.** As you can imagine fiberglass isn’t absorbent but all the space between the fibers can hold onto moisture.
Also, where is the humidifier draining? If it’s not connected to a pipe and being taken out of the crawl space or going into the main drain of the house you could be removing the moisture in the air only to put it back on the ground and, in turn, in the air. Make sure a drain pipe runs out of the crawl space and away from the foundation enough so it isn’t leeching back in. Otherwise tie the drain into an existing drain pipe using a P-trap addition (like under your drain with an [admittance valve](https://www.homedepot.com/p/STUDOR-1-1-2-in-or-2-in-PVC-Mini-Vent-Air-Admittance-Valve-20341/202275238) as required by code.) Or you can get a [condensate pump](https://www.homedepot.com/p/Little-Giant-VCMA-20ULS-230-Volt-Condensate-Removal-Pump-554455/204481232) that will let you drain right into it’s tank and then it’ll pump the water elsewhere for proper removal. This is my solution.
Once the VB is down you should begin to see a difference fairly swiftly. Add some small fans to move air around under the house in addition to the dehumidifier. Moving air means pulling moisture from surfaces, which means wetter air but that’s the job of the dehumidifier.
Another consideration is that you’re getting moisture from something. Take a look at any AC lines running through the crawl as well as any ducting. My old (70s) ducting was very poorly insulated and the cool sheet metal was causing condensation to build up on the outside and drip into little pools which would sit forever. It took almost a year for all of the built-up moisture to go away after I started taking action.
Hope some of this rambling helps. let me know if you have any ?s
You need to get plastic vapor barrier over that dirt floor at minimum. That alone will make a world of difference.
Crawl Space encapsulation will be the ultimate fix for the problem. That will tackle the floor with vapor barrier, the walls with foam board, and the ceilings of the crawl spawn with spray foam.
You also need a vapor barrier over the dirt. do not skimp on how well you seal the plastic. tape all the joints, tape the vapor barrier to the block wall 6″ up, tape the barrier off to the footings below any wooden supports, you want the air under your house to be fully separated from the dirt. Once it’s separated you can get it all dried out an deal with the insulation and any damage.