GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Damp Basement

9ifmFcfNf9 | Posted in General Questions on

I have a row house in Philadelphia that suffers from constant dampness. I have dehumidifiers running constantly, but really need to address the “antique” foundation. Half of the basement is ancient brick (c. 1890) and half very thin concrete (1-2″). The problem is the there is no way to have concrete poured into the space as it is:
a. set back off the street and surrounded by an iron fence
b. down some extremely steep stairs
c. only accessible from the exterior by two small windows
I don’t think I could even get a mixer in the house and down those stairs.

Any suggestions? Thank you for your time!


GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.


  1. jklingel | | #1

    Hayley: Is your floor dirt, or concrete? If bare dirt, it may help to lay some visqueen down on the ground and up the side of the walls a foot or so. Tape/goo the visqueen to the walls. The first thing to check, or fix, is drainage outside. Is water directed away from the foundation by properly sloped land and gutters and down spouts working well. Is the basement heated?

  2. richmass62 | | #2

    Hayley -- check out my posts under energy-efficiency-and-durability titled:

    basement-insulation-1930-house-retrofit-wall- (and)

    I haven't fixed my problem yet but I am taking steps... the first one was regrading the back yard as suggested by John, which solved the problem of wet walls but did NOT solve the problem of wet floors.

    To address the water under the foundation, we had a contractor dig a trench in the part of the basement with the greatest exposure to outside water. The trench in our case needed to span the entire wall, and is filled with rocks (1.5" bluestone). About 14 inches down there is a perforated pipe that directs water outside. When we did the digging in May, just after the wettest part of the year, we discovered standing water about 15 inches below the basement floor. In our case we could direct the water to the yard and street with no sump pump, but in your case you might need one in the lowest part of the trench.

    If you do this exploratory digging it will tell you whether there is water present, and whether a sump pump would help.

    If you actually want to use the basement then you probably can replace the concrete. We had a portion of our basement jackhammered and the mason used about 40 bags of concrete, poured it right over bottom half of the old concrete floor, costing us some headroom! Since it was a very dry section, no vapor barrier or drainage rock were used, and the new concrete does not wick up the moisture like it used to. At least we have a dry place now to store stuff from the main basement floor, which is also slated to be dug up and replaced, using a layer of drainage rock and a plastic vapor barrier under the concrete.

    In your case, they have concrete trucks with a pump that can send the concrete through a long tube. The bigger problem is carrying hundreds of buckets of dirt out of the basement... but it can be done, and you can get a roll-off dumpster for under $400 to carry the extra fill away. Hope this helps!

  3. GBA Editor
    Martin Holladay | | #3

    Talk to a contractor; anything is possible if you can afford the work.

    Your basement floor can be lowered by digging down and removing the dirt. Drainage measures can be installed, indoors or out. Concrete can be placed where necessary, using a concrete pumper and hoses. There are solutions to all of these problems; all you need is a checkbook.

  4. davidmeiland | | #4

    Martin, my feelings are hurt, you're making contractors sounds so ... expensive!

    You might get a real bargain in a situation like that, for instance, a company that likes fixing old buildings and knows exactly how to remove the soil and place a slab in the fastest possible time for the lowest possible money. It could actually work out really, really well.

  5. GBA Editor
    Martin Holladay | | #5

    I feel confident that I have not genuinely hurt your feelings. However, your exaggerated expression of injured honor gives me an opportunity to clarify my point.

    If Hayley was hoping that this was a DIY job, he or she would probably regret the decision. In most cases, a competent contractor able to do this work would certainly be worth every penny.

    Since Hayley appeared to be unaware that concrete can be pumped, it sounded like Hayley was willing to wing it instead of talk to a contractor -- perhaps in an attempt to save money. But I'm just guessing.

    I advised Haley to call a contractor because that's the best approach for a job like this.

  6. 9ifmFcfNf9 | | #6

    Wow, guys! I am impressed and thrilled that I have had such a great response. To answer John's question, I do have gutter issues that are stated to be addressed. I do think it will help with some of the issues.
    I appreciate Rich's ideas very much along with the feeling that I am not alone.
    Martin has the pat answer. Ironically, I did have a contractor come to give me a bid and he was the one that lead me to believe that getting concrete pumped in was going to be a problem. I asked him if taking one of the small windows out would solve the problem and he still seemed stymied. Perhaps he was one of the guys that get's a bad wrap on Angie's list. I am encouraged to look for a more qualified contractor.
    However, I am not adverse to doing as much as I can. I must admit, however, I have no desire to "grow a pair" and try to manage this on my own. Thanks for all the input! I am so glad you are all out there. You Rock!!!

  7. 9ifmFcfNf9 | | #7

    Also, thanks to David for sticking up for all the broke people of the world. I am no money bag and will get a few bids to make sure I am not overpaying and hear what everyone has to say. I'll post some pics when it is all done. Thanks again!

Log in or create an account to post an answer.


Recent Questions and Replies

  • |
  • |
  • |
  • |