+ Reply to Thread
Page 1 of 2 12 LastLast
Results 1 to 10 of 11
  1. #1
    Join Date
    Nov 2009
    Posts
    5

    Default HELP! Water in walls, no detectable source

    Three years ago I bought a brick row house in Washington DC, built in 1893. In May 2009 I had the front (north) wall repointed and repainted. In June, I began to notice a musty smell near the north wall on the top floor, then also on the floor below. There is no visible sign of water damage. I called in my roofer and plumber and the mason, and then two industrial hygienists. The roofer, plumber and mason found no problems. The hygienists confirmed there is water inside the walls in various places (behind both drywall and plaster), but they could not locate the source. All the contractors agreed that a pipe leak should be causing visible damage by now. My neighbors with similar houses have no problems, and the previous owner denies any knowledge. The musty smell is much less pronounced now. Clearly I have a problem, but I'm reluctant to start demolishing the walls without some idea of what I'm looking for.

    Could rainwater be migrating through the new exterior mortar and/or paint? Any other ideas? I'm at my wit's end.

    Thanks,
    Nell

  2. #2
    Join Date
    Mar 2009
    Posts
    1,387

    Default Re: HELP! Water in walls, no detectable source

    Howdy, got a humidifier on the furnace? Turn it off. Consider getting a dehumidifier and run it in theses areas to dry out the room. What type of wall insulation? Vapor barrier? Any plumbing pipes in this out side wall cavity? or the ceiling above. I have handled claims where pinhole leaks caused these issues. What type of plumbing pipe? You Need to open the wall an investigate further. Start in the upper room and work your way down. water in walls = mold issues ...

  3. #3
    Join Date
    Nov 2009
    Posts
    5

    Default Re: HELP! Water in walls, no detectable source

    Dear Tim (May I call you Tim?) -
    Thanks so much for responding! Furnace? No - I have a boiler and radiators. There is no insulation, vapor barrier or plumbing in the north wall. There is some plumbing in an intersecting wall, and I guess that could have a pinhole leak that allows water to seep along a joist to the north wall and then down from there. . . What kind of contractor could best investigate that? A plumber, but they aren't necessarily equipped to deal with mold if they find it.
    Thanks,
    Nell

  4. #4
    Join Date
    Aug 2009
    Location
    Ladson,SC
    Posts
    192

    Default Re: HELP! Water in walls, no detectable source

    Quote Originally Posted by DCSwann View Post
    Three years ago I bought a brick row house in Washington DC, built in 1893. In May 2009 I had the front (north) wall repointed and repainted. In June, I began to notice a musty smell near the north wall on the top floor, then also on the floor below. There is no visible sign of water damage. I called in my roofer and plumber and the mason, and then two industrial hygienists. The roofer, plumber and mason found no problems. The hygienists confirmed there is water inside the walls in various places (behind both drywall and plaster), but they could not locate the source. All the contractors agreed that a pipe leak should be causing visible damage by now. My neighbors with similar houses have no problems, and the previous owner denies any knowledge. The musty smell is much less pronounced now. Clearly I have a problem, but I'm reluctant to start demolishing the walls without some idea of what I'm looking for.

    Could rainwater be migrating through the new exterior mortar and/or paint? Any other ideas? I'm at my wit's end.

    Thanks,
    Nell
    My guess would be that the exterior repoint work was completed using the wrong material like very dense portland cement mix and i would guess that the paint if installed over the bricks was an elastromeric type paint all of which would direct any water to the interior of the wall. If it was ok from 1893 until 2009 what changed? As for piping being placed in masonary walls in 1893 i don't think this whould have been done Piping installed after 1893 would have been in a chase.
    Check the top of the wall if it terminate at the roof joist bearing point it could be a roof leak I have also seen drain lines that were left to drain on to the top of the wall from A/C and water heaters. If the moisture has been between the brick and the plaster for over a year you should have plaster failure like delamination or detachment or if plaster is cracked you will see brown stain outlining the crack.

  5. #5
    Join Date
    Oct 2009
    Posts
    25

    Default Re: HELP! Water in walls, no detectable source

    This sounds like condensation inside the walls caused by something that you did in 2009. It probably wasn't the pointing, even bad portland cement mortar wicks water both directions. But maybe your paint is trapping moisture that always used to be able to flow out through the walls. If you have a boiler and a radiator system there is plenty of humidity in your house and it needs a way out.
    The dehumidifier is a good idea, but I be very afraid that you have mold in the back side of your plaster or sheetrock.
    I'd locate one of those micro inspection camera that plumbers use to inspect pipes and poke that into the wall looking for condensation and MOLD. It could also look for dead animals that will product a heck of a smell. Also put a humidity sensor in the wall to figure out what the humidity is in the wall. If it is really high you could try to vent the wall Iat the bottom and top) to the exterior to slow what ever process is going on.
    Good luck.

  6. #6
    Join Date
    Mar 2009
    Posts
    1,387

    Default Re: HELP! Water in walls, no detectable source

    Quote Originally Posted by DCSwann View Post
    Dear Tim (May I call you Tim?) -
    Thanks so much for responding! Furnace? No - I have a boiler and radiators. There is no insulation, vapor barrier or plumbing in the north wall. There is some plumbing in an intersecting wall, and I guess that could have a pinhole leak that allows water to seep along a joist to the north wall and then down from there. . . What kind of contractor could best investigate that? A plumber, but they aren't necessarily equipped to deal with mold if they find it.
    Thanks,
    Nell
    Howdy Neil, call me Tim . Is the top of the wall cavity open into the attic or has a top plate( usually 2by4"? What type of attic insulation? Do you have exhaust fans in the bath rooms? any bath rooms close to this north wall. I ask because the humidity given off from shower if no exhaust fan I would have one installed and run on a timer to get the moisture out of the house. The type of would be a restoration contractor not a plumber. Plumbers want to charge plumber rated for unskilled general labor so price alone is cheaper with a general contractor. Opening a small observation hole or two in the wall after checking the attic for insulation would be a good next starting point. If your interior wall and ceiling is painted then you have a vapor barrier of the paint ... yes oil base is the better but somewhat even with latex. Hope the repair is a inexpensive one.

  7. #7
    Join Date
    Nov 2009
    Posts
    5

    Default Re: HELP! Water in walls, no detectable source

    Hi, Tim! The top of the exterior wall is visible in the attic, under the roof, and it's dry. Attic insulation is blown in. There is a bathroom on that wall, and it does have an exhaust fan which I run during and maybe 15 minutes after every shower. Walls and ceiling have latex paint, and exterior wall also has latex (exterior) paint. I'll see about making some openings for observation, but not with a plumber! Thanks for the advice. Nell

  8. #8
    Join Date
    Nov 2009
    Posts
    5

    Default Re: HELP! Water in walls, no detectable source

    Hi, Hank! Thanks for responding. The mortar was Type O, which I was told by historic preservation experts is the right type for circa 1893 mortar. The exterior paint was Benjamin Moore, but I don't know which particular version. No roof leak or drain lines leaking, and no visible damage to plaster or dry wall. Looks like I need to open the wall! Thanks again. Nell

  9. #9
    Join Date
    Nov 2009
    Posts
    5

    Default Re: HELP! Water in walls, no detectable source

    Hello, LogDoc! Thanks for your reply. Dead animal is unlikely, as it doesn't smell THAT bad. All signs are pointing to a probably pinhole leak in a pipe somwhere in an intersecting wall, so I will probably have to start making larger holes to investigate. Thanks for your help. Nell

  10. #10
    Join Date
    Aug 2008
    Posts
    109

    Default Re: HELP! Water in walls, no detectable source

    If your wall plaster is upon expanded metal lath moisture readers are going to register (falsely) high readings behind your plaster even if there isn't a moisture issue.

    I agree with previous poster about the pointing work and painting likely contributing (walls can't respirate). Window and wall flashing might have been damaged also.

    You'd have to know if your plaster is applied directly on the brick, or on wood lath (on strapping), expanded metal lath may be with strapping usually not, or on gyp or rock lath (on strapping over brick), I've seen all three in DC circa 1900-1950 construction (and once all three in the same row house).


    Source might also be between the wythes (layers of brick in the wall) up near the shared walls or roof. You probably have three wythes on two walls and two on the other walls.

    If the problem is only on the lower floor then suspect plumbing traveling along the ceiling out to the wall then down the wall behind the plaster. Do you have old style expansion tank up in the attic for the old boiler or any steam/hot water piping up there that is another potential source of moisture between floors that can travel in the cavity and pour between inner brick wythe and plaster or down inside walls.

    Is your bathroom exhaust fan vented to the outdoors or to the attic cavity?

    What are you doing for cooling/dehumidification in the summer? A/C? Where is the coil, the condensor? Draining condensation or a pan might be the source depending on where your appliances are located. Other thought is that windows open/window sills are the source - i.e. rain - but not so much if this is only inside walls not exterior walls to the row house. Perhaps you have storms up or windows closed and that's the reduction of the smell or perhaps no AC running is the difference (condensation pan or drain line).
    Last edited by Gray Watson; 11-18-2009 at 07:08 PM.
    SPAM: never liked it from a can, can't stand it on a board forum. This board needs MODERATORS!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •