Dear PoP – Fixing Basement dampness

Photo from basement dig out post

“Dear PoP,

I am in the process of getting the basement watertight. One way I am doing this is by removing half of drywall in the inside and repair the brick and paint it dry-lock. The other part is to get the soil in front of my basement windows removed and make it the same level as my basement entry way and build a retaining wall; however, I know there is water line that will be there probably 6″ or so from the basement floor. With soil gone, what do people do to winterize the newly exposed outside portion of the main water line?”

I’d also be curious to know what other steps people take to keep their basements dry. I don’t know about a water line but I’ve been running a dehumidifier 24 hours a day. I wish there was a less expensive solution. What do you guys do?

27 Comment

  • brookland_rez

    When I bought my house, the basement leaked water. The prior owners just had some paneling attached to 2×2 attached to the brick. The wood was full of moisture, so I demoed all of it out, took it back to the brick. I found a number of cracks in the brick as well as a 2 inch wide gap where the wall met the floor. I patched all the cracks and holes, scraped all the loose existing paint on the walls, cleaned the walls and floor with an anti-bacterial cleaner. I painted the walls and floor with two coats of Killz, and went over the floor with a garage floor paint. I also sealed around all the windows and patch a crack between mine and my neighbors porch where water appeared to be running in.

    I have had no problems with water since, and have no mold in my basement. I run a dehumidifier 24/7 anyway, helps to keep mold from possibly forming.

    • Is your basement below ground? I have a basement that has a garage but the front of the basement is below ground under my porch…

    • How did you get the loose paint off the brick walls? I have the same issue but have been avoiding it because the paint is old, in terrible condition, and I don’t want to contaminate the house with lead.

  • Another option is to remove the soil and place a plastic barrier outside and replace soil. With an addition ours was done this way and the only water that has been an issue was related to roof and door issues.

    On the older portions of the basement, drylock and garage paint in exposed areas of hte floor worked.

  • Similarly I took out the paneling that was there and found that the 2x4s holding it up were rotted. I scraped the brick work, patched up cracks and holes, added a good hand of Drylock, and then I covered all the walls and ceiling joints w/ Tyvek. I put up drywall on most of the walls, but put up the old nice notty pine paneling up on 2 walls (it was in very nice shape). During the winter the basement now isn’t as cold and this summer it has maintained cool and not very damp. I do run a dehumidifier every other day.

  • Few things are more important and more overlooked by property owners than proper


    Walk the perimeter of your property, observe the grade and footprint of your house upon that grade, and ask yourself when it rains and snows where does the storm water flow to ?

    Where do the gutters and downspouts drain to ?

    Do they drain away from the house ?

    If not why not ?

    Take remedial action so that when it rains everything flows as it should directly into clear gutters and not down the exterior walls and down downspouts with long lower extensions upon sloped ground away from the house.

    • I checked my rear drain. There is no obstruction, however it does not drain properly. I’m getting water in basement now. Do I call DC Water (WASA) to fix it?

      • you call a contractor. why should DC WASA have to deal with it?

        • Because the drains connect to WASA pipes.

          The Obstruction might be there…

          Call WASA and have them come out. I had a similar problem, they came out, snacked a backyard drain, and wa la… dry as a bone.

          Although, as NON 12:32 says – drainage!

      • Umm, you call a plumber. Why would you think your personal drain is somehow the cities problem?

        • My backyard drain (not inside my house) belongs to the city, runs the length of the row houses, and is managed by WASA…

          That is why it is the city’s problem.

          • So the drain it isn’t on your property? Odd…you must have one of those futuristic “floating” houses that manages to hover above ground. Perfect I’d say…all the benefits of owning a house without having to pay property tax.

            I hate to point out the irony of your non-drain considering you used the term “my backyard drain”. Do you or don’t you own your backyard?

            It the cities problem when it reaches your property boundary, not an inch before.

          • Frankie: Call a plumber dude. You’re responsible for the drain that connects to the main line, even if it extends past your property line. If the obstruction/problem is in that drain, have it fixed. It’s not that expensive. It cost me about $700 total and that covered the initial visit/testing the plumbers did and the follow trip to correct the issue. Which involved cleaning out the pipe and redoing some thingamajig that connects to the whatdoyoucallit.

            I really think homeowners take basement dampness way too lightly. I say this from personal experience. If you’re basement is consistently damp, there’s water collecting somewhere along your foundation and soaking into the structure. Check your waste/water lines, check your drainage and regrade your yard. None of these things are super expensive and will save you a lot of headaches and money down the road.

          • The city owns any property which does not include improvements. A drain in the backyard connects to WASA’s sewer, making it their responsibility.

          • ah

            In theory true, but you are responsible for the water supply pipe from the property line and same for the sewer.

            That said, can’t hurt to see if WA, er DCWater!, will come fix it for free.

            And +1 to all the drainage points. You can’t block water with paint–you need to get rid of the source of water first, then look for ways to keep the limited water remaining outside, which includes digging out around foundation and putting in plastic sheeting and such. But that’s expensive.

            Basements around here will be inherently damp still-gotta use a dehumidifier for that. Or A/C if you’re running it anyway.

          • Constantly amazed at how shockingly little most homeowners apparently know about “homeownership”.

            Your house isn’t a condo, and the city not your HOA.

          • Funny, AFTER I called a plummer who snaked my drains, which connect to the WASA drain, WASA came out and snaked THEIR drain which runs through my back yard, side to side, not to the alley or street. My share of the issue was corrected and then WASA did their part (just as my expert plummer advised.)

            Perhaps my wording wasn’t clear. The drain in my back yard runs parallel to the street in the front along the back of all the houses. WASA’s name is on the drain cover and it serves all the neighbors… OK?

            NOT my responsibility to keep that clean.

            You “experts” should read the post completely before you preach – JOKER. Oh yeah… floating house – idiot!

            Regardless, my basement is completely dry and has been since I bought the house over a year ago and fixed the problem.

            Constantly amazed at how shockingly – ignorant most people are in this site.

    • bfinpetworth

      I had a small flooding problem two nights ago during the heavy rain. Water collected in the bottom of the concrete stairway to my rear basement door. It looked like the drain outside the door was overwhelmed, but it took a good while to drain.

      After reading this, I called the City water department – was told that I’d need to call a plumber to snake it, but that it probably just couldn’t handle the flow of water. The downspout from the rear gutter is also directed into a ground drain, and I suspect that all that water overflowed into my basement stairwell. My next step will be to redirect that downspout to the back of my (very small) backyard. Ugh.

      • ah

        You may be able to do this yourself: Take a hose and put a spray nozzle on it (the straight kind). Slowly push the hose down into the drain and keep pushing. With so little rain there may be a wad of leaves down there. You may well be able to blast it out with some water pressure.

        Then redirect that downspout.

  • You should never expose a waterline above the frostline. This is bad building practice and will cause problems down the road when it freezes (not if). There are lots of products out there that will do a great job if you apply them to your foundation and then backfill it as it was.

  • Get rid of any drywall or paneling that is hiding the foundation. Old basements were never meant to be finished, and I can’t believe so many people live in them around town. Consider buying a powerful dehumidifier– not one that you get at Home Depot, but a serious model by Santa Fe or Aprilaire. These consume less electricity, won’t run 24×7, and will last a lot longer than the plastic models you can buy off the shelf. They cost a lot more (upwards of $1000) but you will recoup that premium in efficiency and longevity over the years. A proper dehumidifier in the basement can lower the relative humidity throughout the entire house.

    If you have actual water running in the basement, through the floors or through the ceiling, you might need a drainage system installed.

  • Watch holmes on homes, he makes this look easy.

    You need to water proof the exterior all the way down to floor level, NOT the interior surface of the foundation to keep the water out. If you just watertight the interior surface, you trap the water in the wall and that is not good, especially if it freezes there. CRACK.

    Second, you will need to attach weeping system to the interior surface of the wall, so if you do get water inside, past the exterior coatings, you can keep it off the finished surfaces. Is like a corrugated plastic that channels water.

    The weeping system inside will then run down the wall into a perimeter drainage system under the floor that drains into a sump pump. A good foundation contractor could probably do this for you in a couple days, say around $4,000 or so I would guess.

    Finally, inside of this, you can put up regular stud walls and finish as you like and you should not even need to dehumidify.

  • Wow, 20 replies later EMP actaully addressed the orginal post. Thanks! So my only option is to backfill the soil after covering the outside wall?

  • we used and they did an amazing job. It was not cheap but they were in an out in one day, and now we have a 100% moisture free basement with invisible french drains and a sump pump. such a reassuring sound to hear the whoosh of the water coming out during even light rain.

Comments are closed.