Dear Angie: Is it better to waterproof a crawl space inside or outside? My husband and I just bought a home that has some pooling water in spots in the crawl space. There are three sump pumps in the crawl space now. We also have a very low crawl space, about 2 feet. It has a cement floor.
We have had four companies give us estimates and their suggestions. Two said outside waterproofing including an outside French drain were needed. The other two said a French drain inside the crawl space and encapsulation was the way to go.
There is mold in the area, and wooden joists are starting to rot, so we want to get this problem taken care of ASAP to avoid further issues. Which of the two is the better, longer-lasting solution? — Lisa K., New Baltimore, Mich.
Answer: The solution to your water problem depends on a variety of factors, such as if you have a block or poured concrete foundation; where the water is coming from — through the walls, up from the floor or out of the sump pump; if you have a storm drain near the home; and the angle at which the ground around your foundation is graded.
It could even be as simple as a sump pump failure. Before investing too much time and money into waterproofing, it might be worth it to contact a qualified plumber to check your sump pumps. Often, sump pits fill with rocks, dirt and sand, which cause the unit to malfunction. A qualified plumber can run a camera into your sump pit drain lines to see if there's a blockage or other issues affecting the operation of your pumps.
That said, there certainly is more than one option for dealing with water penetration issues, so it's possible that an interior or exterior waterproofing method will work. If the crawl space needs a complete waterproofing system, it's possible that the exterior method wouldn't work, as driveways, porches, decks, etc. can impede the excavation process. However, because the space is only 2 feet tall, it's also possible that it's simply too small for inside waterproofing.
Because there are so many factors, it's difficult to offer you clear advice without a qualified person seeing the crawl space and identifying those variables. However, I did reach out to several highly rated c ompanies in your area that deal with basement waterproofing, and the general consensus was to not encapsulate the crawl space but to address the source of the water entry, drain it, dry it and remediate any mold. Again, this advice could change depending on your situation.
Unfortunately, if you're soliciting advice from companies that do interior or exterior waterproofing — but not both — you're more likely to get conflicting information with each type of company recommending their particular service.
That's why my recommendation is to find three local waterproofing companies that offer both interior and exterior waterproofing.
A company that offers both services should be able to provide you with options to find the best solution for your situation. Plus, by talking to three companies that offer both services, you're likely to get consistent opinions or at least identify if one company offers advice that conflicts with the other two.
Because it can be so difficult to know whether the information you are getting is accurate, it's important to hire a company with a track record you can trust. Read unbiased, online reviews. Before you hire, ask for a list of previous customers, and ask some of them how the company worked out for them.