I noticed a vertical crack in the wall from the baseboard up to the window above it, Vertical crack was first sign of trouble so I pulled off the baseboard to investigate. I saw that the drywall under the baseboard had cracked and crumbled away in a few spots. I pulled off a chunk of the drywall (about the size of 2 or 3 fingers), and much to my surprise a handful of dirt/soil/earth came out! I then used a screwdriver to jab the drywall (just below the height of the baseboard) which easily crumbled and came loose. If it didn't break up easily I skipped ahead to try the next spot. I did this along the length of the wall and about ¾ of it had this problem. Drywall beneath molding had weakened and crumbled easily

I then stuck an inspection camera inside the opening and mostly saw insulation. Where I was able have an unobstructed view, I could see lots of cracking. Inside the front wall of house.  Shows cracking which allowed dirt to enter wall I could also see outside light coming into the wall's interior when the room was darkened.

Next, I went outside to find the place where the light was entering the wall. I started by digging some of the ground away from the foundation down to about a foot. Dug some dirt away from foundation looking for a means for dirt to enter wall The concrete of the foundation appeared to be in good condition and did not reveal any cracking or any openings leading inside the house. close-up of exposed foundation as seen in previous photo, seems OK

To find the light's point of entry which I saw from inside, I referenced a corner of the window to measure offsets down and along the wall to the problem area inside the house. I then used these measurements to measure from the same corner of the window on the outside of the house. The specified location was a point just above the boundary between the foundation and the facade of house. This was confusing at first because no deterioration was apparent. facade is free of holes or openings leading to inside of wall The reason was because although the surface of the facade was intact, it had separated from the rest of the house which could only be seen by looking upwards from the ground. gap between wall and facade as seen looking skyward from pit shown in photo 4 The tape measure would not be able to penetrate the gap between the facade and the wall were it not below the level of the ground and pointing skywards. tape measure shown extending up into gap behind facade

To verify that the point of entry on the inside of the wall actually exited the exterior wall at the indicated location, I was able to stick a tape measure into the wall from inside the house, tape measure shown penetrating wall to verify exit on exterior side of wall

and see it in the gap from outside the house. tape measure shown protruding into gap as seen from exterior side of wall This also was a way to measure the size of the gap (about ¾").

What I would like to know is: what could be the cause; how serious is this; what should be done to prevent this from continuing; and how to repair the damage?

The only answers I can hazard are:(null); not serious at all; just ignore the problem, it will go away by itself; for the interior, use "great stuff" expanding foam in the interior of the wall, trim to be flush with the inside surface of the drywall, and then use Plaster of Paris (which I have never used and have no idea of its working viscosity) to replace the missing drywall (or cut off the jagged edge of the drywall and cut a strip of drywall to fit into the empty space), and for the exterior of the house I would seal off the gap by troweling some mortar into the first inch or two of the gap. (These kind of "solutions" are the reason I'm asking for advice!)

EDIT: (I've just accepted the answer, but I thought I'd update with some more info.)

I think what I have learned is that the foundation of a house should always be above the level of the ground surrounding it. What has happened in this case is that this house had a 2-car garage which was remodeled into a master bedroom. Then the front wall of the garage-turned-into-bedroom had a giant flower bed built onto it (in the way you might see a flower box hanging outside of a window). garage remodeled into master-bedroom with giant flower bed built onto it The left side of the above photo show the same area as seen in photo #4, only from a slightly different angle and further back and after I filled in the hole. Photo #5 shows the foundation after I dug away some dirt, as well as the bottom of the (fake) stone facade. This is where the problem is because the foundation, facade and ground all meet at this level. This is why the dirt/soil/earth came out from behind the baseboard, because it was always right outside. The next photo gives photos# 7 & 10 some perspective from the XYZ axes I drew. (The ground is parallel to the XY plane.) perspective for photos# 7 &10 Also notice what is between the red lines. This is a 2x4 which lies flat on the foundation so you can see just where the foundation is/ends. Here is that same 2x4 as seen from inside the house: same 2x4 as seen in photo 12 When I look at photo# 3, I think it wasn't much help because, like, What is all that stuff? This one is hopefully better. enter image description here The red line is calling attention to the edge of something which I think is that black tar paper stuff used as a vapor barrier to block wetness. It is still attached to the vertical stud (to the right, from our perspective). You can tell, because the shadow cast onto it is very thin. The green arrows point to the stud from the previous photo. The black lines are meant to be parallel to each other and to the 2x4 (the ground). They represent the size of the gap (the facade separated from the house) and is equal to the blue arrow.

Luckily this house is in the dry desert climate of Nevada, so at least the damage isn't as bad as it could have been. (I installed a Panasonic "Whisper Warm" - I think that was the name, it was "whisper" something - which was kinda expensive but WELL WORTH the money because it really is quiet. Highly recommended if you can't stand how irritating a noisy bathroom exhaust fan can be. Anyway, when I installed this fan, and I was removing the old one, I saw that it had never been hooked up to vent outside! Not that it had broken or was disconnected, there never was any kind of vent or opening for that slinky-exhaust-tube-stuff to attach itself to! And the old exhaust fan was old. I mean o-l-d OLD! Probably original to the house so that means 40 to 50 years old. And all that time the showers taken in the bathroom just vented into the attic!) Long story still long: although there is water damage present, it's not as bad as it could be. But thanks for the help because I can now give a somewhat competent report to the owner who of course is the one making the decision.

  • Foundation is at or below grade. That's no bueno.
    – Mazura
    Commented Sep 28, 2021 at 22:58
  • WOW, COMMENTS RULE!!! I'll bet you just solved the whole situation. What I understand you're saying is that the level of the ground should never be at or above the top of the foundation. After you gave me the answer, it seems like first-day-of-class-in-common-knowledge-101. But, well, I did not know that! So here's what I left out of the question because I had no idea it was relevant or important enough to be worth mentioning: The wall in question was a modification which converted a 2-car garage into a master bedroom. Then a low retaining wall (I may be taking liberties with the...
    – TRS-80
    Commented Sep 28, 2021 at 23:14
  • 1
    jargon) was put around the front of the wall to create a huge 8' x 20' (guestimating) FLOWER BED in front of the new master bedroom wall with massive window for viewing all the beauty of nature growing just outside! So it is just this front part of the house that has the foundation at or below grade. Rest of the house should be sufficiently bueno! I will add all of this to the question and add some photos showing other parts of the house that presumably have a situation with the foundation that is up to snuff. Granted: I've gone all in on your 9-word comment, but my gut is sayin THAT'S IT!
    – TRS-80
    Commented Sep 28, 2021 at 23:28
  • 3
    Well researched, asked & documented question!
    – FreeMan
    Commented Sep 29, 2021 at 14:24

2 Answers 2

  • Drywall Crack - That is a likely the factory joint of the drywall. It cracks due to movement of the studs that can happen for a variety of reasons, including temperature, humidity changes and settling. Will crack more easily if it isn't properly taped and mudded. Fixing it properly requires cutting out the old tape, filling (I prefer elastomeric caulk) any gaps, redoing the tape & mud and any texture, repaint.

  • What causes the drywall to crumble like that - Water. As you have found you have a hole that has let in dirt and moisture (and likely insects). That water is likely what has caused the flex and moisture issues. That water could be coming from where you see the gap or it could have originated at the window (or higher)

  • Is it bad? Yes, very. Water, both suddenly and over time like this, is the worst thing that can happen to a house short of fully burning down. Insurance often won't cover damage caused by slow water intrusion like this (nor the insect or other damage that follows). It is critical to find the root issue and properly fix it. Hopefully it isn't a large fix, but any water intrusion is worthy of 'very bad' levels of concern.

  • Can you use foam and other patching to address it? - No. The hole is likely a symptom, not the issue. And it looks like the exterior wall isn't even on baseplate anymore. Also, Great Stuff open cell foam should never be used around moisture as open cell foam sucks it up if the skin is cracked. It is only good for air sealing in dry areas.

  • Recommendations:

    • As Mazura stated, it looks like your dirt is higher than the foundation. If that is the case, it needs to be dug out and regraded around this area.
    • You need to find the root of the water intrusion and determine the extent of the damage (how high is it, is the wall even on the foundation or has it flexed out, etc). Since you need to do drywall repair anyway, I'd recommend starting by cutting the drywall out under the window (along the middle of the stud take make it easier to attach a new piece of drywall). Remove the insulation, and see what you see. Test the outer sheathing with a screw driver to see if it sinks in, indicating rot. Being solid on the inside doesn't mean the outside hasn't started to rot but it will at least give you an idea of next steps without having to start tearing off the rocks on the outside.
  • 1
    This pretty much qualifies as an answer, not a comment anyway, so well done. Also, tweaked the formatting to make the "Recommendations" section a bit easier to read.
    – FreeMan
    Commented Sep 29, 2021 at 14:22
  • What do you mean by, "the factory joint of the drywall" ?
    – TRS-80
    Commented Sep 29, 2021 at 20:46
  • (re: " The hole is likely a symptom, not the issue.") It's not just a hole, it's like an entire vent! The gap made when the facade pulled away runs pretty much the whole length of the wall, and on the inside, the drywall doesn't meet the floor for about 3/4 the length of the wall. If the vertical studs show signs of rot, that's going to become a structural integrity threat, no? Oh, and BTW, thanks for the answer!
    – TRS-80
    Commented Sep 29, 2021 at 20:53
  • Factory joint and butt joint are the names for the two type of seams between two pieces of drywall. Factory refers to the tapered edge along the long end of drywall pieces. Factory or butt isn't really relevant as far as actions are concerned so you can ignore that aspect and just note that the crack is just happening at the joint between two pieces of drywall. As for the it pulling away along the length, that does need attention. If it isn't rotted already it will be. Structural if the wall is supporting something above it, yes. Very likely you'll need a contractor out to fully assess.
    – Mike P
    Commented Sep 29, 2021 at 22:34
  • 1
    Just saw that you added pictures and details. Holy smokes, yeah that is a bad gap and no way in the world should they have built that raised garden bed up against the house like that. No question that you have been saved by being in Nevada. Here is western WA that wall and room would have had severe water damage by now. And it is definitely the situation where you are going to have to remove that dirt and get a contractor to mitigate the damage and determine best way to repair that wall as it isn't a minor fix unfortunately.
    – Mike P
    Commented Sep 29, 2021 at 22:42

Given the size of the hole, and the locale, that 'dirt' in the wall could have been wind-blown in. If the fake stone facade is attached to the outer sheathing and the weight pulled it away, that likely needs to be torn down and replaced. Consider removing the flower bed dirt from next to the house, leaving a gap out to the surrounding area, and fill with appropriate materials. Its under the roofline, given a rare rain and likely flower bed watering, a French drain covered with stone is one idea. Use landscape cloth up against the exposed flower bed dirt. Yes it has been a few years since the post, but I did not see these topics addressed.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.