We are of the belief that you should have virtually zero tolerance for water on top of the vapor barrier under your home. This distinction of on top of the barrier is important and we will explain. But why so strict when on top of the barrier? Because it is easily achievable to have a dry crawl space and the risk of allowing anything more than zero does not seem like one taking.
When we find water in the crawl space we usually tell homeowners to have a mold inspection in their attic. More often than not there is mold discovered. And in our experience the inverse is true, a dry crawl will usually yield a passing grade from a mold inspection. Why is that? Well, mold needs 3 things. Moisture, oxygen, and darkness. Just eliminate one of those factors and we severely limit molds ability to spread. Eliminate two factors it would seem exceedingly rare that mold could replicate in such an environment.
We can severely restrict and/or eliminate the moisture by installing a drainage system under the home with a PROPERLY installed vapor barrier (notice the emphasis). That black plastic in your crawl space does serve an important function. It’s job to keep soil gasses and moistures out of the crawl space and in turn out of your living space is an important one. Often there is no need to install a drain system. The rips and tears in the existing vapor barrier along with incorrect overlap of seams might be allowing the smallest amount of ground water to percolate on the barrier and accumulate into standing water. If the vapor barrier is properly installed and in good condition then the water is evidence that the soil has reached maximum absorption and that the water table around your home is too high to just have a vapor barrier without drainage below it. The best way to increase the soils ability to absorb water, and the only way that I have heard of? Remove water from it with a drainage system and generally one that ends at a sump pump.
You will never hear anyone at Better Basements tell you that a home with proper drainage and a dry crawl space will never experience foundation issues. However, we will confidently tell you that major foundation issues are often caused by running water and poor groundwater management. Why and how is that? Running water carves canyons and creates mountains on the earths surface. The clay and soil around the foundation of your home truly stands no chances up against an Oregon Winter and Spring rainfall. Then when it settles your foundation ever so slightly to create a crack, water will easily find it’s way into that crack and begin to carve it’s own canyon. So is water in and around your home really THAT big of a deal? Only if you think your foundation is a big deal.
“All homes have water in them, this is Oregon. Can you even stop it?”
This is my favorite push back. Because if we are making these statements then it would seem I have convinced you that water in your crawl space and standing water around your home is in fact a big deal. Now I get to tell you how simple the solution is, which is why our tolerance for these symptoms should be nearly zero. There is a fix. A straightforward easy fix. AND it is generally done for less than most people are expecting it to be.
Let’s share cost before we share application, then I have a hunch you will think it is a bargain. And we share cost with a very large and obnoxious disclaimer. Many homes are much larger than average, and many homes only need 20 feet of drainage where as the average needs 120’. So what does a full crawl space waterproofing cost? In our experience between $4,000 – $8,000. With the vast majority of homes being in that $5,000 range.
Maybe you think that is outrageous. Well let me share some quotes with you from homes that had their foundation sink from years (or A year) of standing water and we’ll think it is a bargain.
“Okay, fair point, I am not interested in spending $50,000+ for foundation stability and restoration. But I will just do it myself because it is not that much work”. By the way, we love our DIY types. That is how all contractors got started, so if you need advice on how to do this just let us know and we would be happy to sell you some materials and give you advice (still free). Lets just not kid ourselves on it being easy.
- Go under home. Cut up and remove ALL vapor barrier and debris under home. Put into trash bags. Remove trash bags filled with debris. (this usually takes a 2 man crew about 2 hours, and they do this all the time and their fear of dead rats and living spiders has disappeared).
- Decide what proper drain trench placement is. Do you really need to do a full perimeter drain system? Afterall, if we can do 50’ instead of 140’ that would be ideal. Are you prepared to make that educated decision to ensure that you are not going down there in a flooded crawl space on a Saturday morning to right your wrongs?
- Dig trench. Easier said than done and I usually do not need to convince anyone of that. We use mini D-Handle spades. They are about 25” long and work well for digging on your side. Yes, you have to lay on your side and dig trench whilst throwing the soil evenly over your shoulder. This process is obviously the longest and will take a good crew with “good” soil conditions a full day, Generally about 20 man hours.
- Dig sump pump basin pit, lay a gravel base, install basin and surround in gravel (have fun bringing that gravel to the lowest point in your muddy crawl space). Install sump pump in basin and connect with PVC.
- Crawl out of crawl space and install your discharge line (not going to explain how important this part is and how to decide that, alas it is important).
- Install drain pipe/drainage/drain tile or whatever you would like to call it.
- Properly install vapor barrier. So, likely better than the last guy. Which is there can be no earth exposed and all the seams must overlap no less than 12”. BUT, we must keep as minimal seams as possible. Which means you need to use as large of sheets as possible, make tight cuts around your post, and to keep it really professional roll yourself out of the crawl space to ensure it is clean. We even go the extra mile and take a small leaf blower with us to keep any dust and dirt under.
- Finally, you have to be willing to stand by your work. Because you can’t call me for a warranty repair to fix your mistake!
In summary, why should our tolerance for water under our home be nearly zero? Because it is simple to keep it nearly zero and the ramifications of it not being dry can be drastic.
We covered a lot and this is a very brief overview. We did not explain material selection, drain trench or pump discharge placement. Why not do a gravity system? There are reason why you should and should not have a pump. What are some obvious fixes that we can do to see if that fixes our flooding crawl? All valid questions and pushback that have answers. Give us a shout to set up a free estimate or just to ask some questions and have a conversation with someone who has likely seen what issues you are experiencing. We truly love hearing from you.