I had an interesting inspection happen last week that had me thinking about the importance of regular maintenance of your home, as well as a semi-regular inspection of your home to make sure potential problems can be taken care of before they become a bigger problem. During a recent inspection, some fairly large cracks in interior walls were present and some cracking in the mortar of the exterior brick walls were noticed. The homeowner mentioned that those cracks developed over the last year, as well as a new, musty smell. That lead me to take a look in the crawlspace. It didn't take long to figure out that that was the location of the problem. Nearly half of the crawlspace dirt floor was mud. Looking for the source of the wetness, I noticed that the tub plumbing was actively dripping and showed a VERY large amount of corrosion on the copper piping. That indicates to me that it has been leaking for a long while. However, the amount of mud down there couldn't have been from just that leaky pipe. I looked around the mud a little more and noticed some rusty discoloration. I found a stick and scraped away at the mud and found the home cast iron sewer waste pipe under the mud. Not only did the stick scrape away mud, it also scraped away some toilet paper out of a hole in that drain about 4 inches long, allowing sewer gasses to enter the crawlspace. This hole was most likely allowing water to leak down there any time someone did dishes, or took a shower, or ran the clothes washer, or anything that uses water in the home.
So what about the cracks? Well, my guess is that the large amount of water in the crawlspace made mud and softened the ground, including in the areas where the home support pillars for the beam that runs from the north to the south end of the home sits. If those pillars are not supporting that beam (ergo, the whole center of the home), then extra stress is being placed where that beam sits on the perimeter foundation wall. It just so happens that that is where the cracking visible outside was taking place.
Before I recap, let me say that I can be wrong on what I'm proposing, but I believe this is the way things worked.
Leaky plumbing dripped to dirt directly above cast iron waste line.
That water/mud made the cast iron waste line start to rust (note that cast iron drain lines also slowly deteriorate from the inside out as well through normal usage.)
Rust and deterioration of the pipe eventually created a hole in the waste line.
Waste line allows large amount of moisture to enter the crawlspace.
Dirt under support pillars becomes softer and muddy
Support pillars no longer providing adequate support
Extra stress in some areas and lack of support in others create movement and cracking in interior and exterior walls and foundation perimeter.
You may be asking, what's the point of the story? The lesson is that little problems that aren't found and fixed can create much larger problems down the line. The leaky pipe didn't appear over one night. The cracks didn't appear over night. The rust didn't appear over night. But, at any point, if one part of this situation was caught earlier and fixed, future damages could have been avoided. That's why it is recommended that you do an inspection of your home on a regular basis. Walk around your yard and look at your home siding, the windows, the gutters, caulking of gaps, the slope of the ground away from your home. Make sure they look like they are in good condition and performing their jobs correctly. If not, fix it. Check under your sinks and behind the toilet for leaking. Look for new cracks or discolored walls or ceiling. Make sure doors and windows are shutting properly. Replace light bulbs. Replace batteries in smoke/carbon monoxide detectors. Pop your head under the house to the crawlspace and take a quick look for anything new or out of the ordinary. I hop down to my crawlspace every 3-6 months for a quick look around. If you don't want to do the looking around for yourself, get some help. Ask a friend. Or, create a new routine and hire a certified home inspector to do an annual check-up for you. They can write up a report of findings, which you then use as your “honey-do” list of things that might want attention, and then you also have a written record to compare against next year to see that things are being maintained. However you want to do it is up to you, but taking a few minutes every now and then can save you a lot of money and worry.