Signs of Active Movement
These are the things that tell me something is currently happening.
Cracks That Grow
My pencil marks at the ends of my cracks are still exactly at the ends after five years. Gary's marks were inside the crack within three months. That's the clearest sign of active movement: cracks that extend past where they used to end.
Width matters too. My widest crack has been 1/8 inch for five years. If it started measuring 3/16, then 1/4, that progression would mean the crack is actively opening.
Fresh Concrete Dust
Active cracks shed debris. When concrete is moving and grinding, you'll see fresh concrete dust near the crack. Clean it up, come back in a month. If there's more dust, something is moving.
My cracks have accumulated normal basement dust over the years. No fresh concrete fragments. That's what dormant looks like.
New Cracks Appearing
A new crack that wasn't there before is movement that just happened. I've found one "new" crack in five years that turned out to be a hairline I'd missed before. But a genuinely new crack, especially with clean edges and fresh appearance, means something caused it recently.
Failed Repairs
I sealed one of my cracks three years ago. The seal is still perfect. If the crack were active, the repair would have cracked or separated. Failed repairs are proof of ongoing movement. The repair can't hold against forces that are still at work.
What Gary's Wife Noticed First
Foundation problems often show up in the living space before the basement.
The Sticking Door
Gary's front door started needing extra push to close. He blamed humidity, trimmed the door, problem "solved." A year later, trimmed it again. He was chasing a symptom while ignoring the cause. The door stuck because the frame was twisting from foundation movement below.
I check a few key doors in my house during every inspection. Same behavior every time. No new sticking, no new rubbing. That consistency is what I want.
Windows That Won't Open
Gary's wife mentioned a bedroom window that got harder to open over time. Again, he made adjustments instead of asking why. The window was in the frame above his bowing wall. The foundation pushing in was distorting everything above it.
New Gaps
Gaps opening between walls and ceilings, between wall sections, around door frames. Gary's wife pointed out a gap in a corner that she was sure wasn't there when they moved in. She was right. The gap was new. Different parts of the house were moving relative to each other.
Drywall Cracks
Diagonal cracks from door and window corners. Classic sign of frame stress. Gary had developed several by the time he finally called someone. They traced right back to the foundation problem. Different symptoms, same cause.
My Detection Methods
What I actually do to confirm my foundation is stable.
Crack Monitoring
Pencil marks at crack ends, measurements at the widest points, photos with ruler for scale. If anything changes, my system catches it. Five years of identical data proves my cracks are dormant.
Wall Plumb Checks
I hold my 4-foot level vertically against each wall at several points. Looking for any tilt. My walls are plumb. Gary's wasn't. His was out by almost two inches at the top when we finally measured it properly. That's movement you can detect with a $15 level.
The Golf Ball Test
I roll a golf ball on my floors in a few rooms. It always rolls the same direction, toward the same corner. Slight slope from original construction, been that way for 45 years. If the ball started rolling differently or faster, the floor's tilt has changed.
Door Function Test
Open and close key doors. Same behavior as last time? Good. New sticking or rubbing? Investigate. My doors have operated identically for five years. Boring is good when it comes to foundation movement.
Visual Wall Sighting
Stand at one end of each wall and sight down to the other. Any bow or curve would be visible. I do this in the basement and upstairs. My walls are straight. Gary's basement wall had visible bow once you knew to look. Maybe an inch and a half at the worst point.
Historic vs. Active: The Key Distinction
Everything in an old house has a history. The question is whether that history is ongoing.
Historic Damage
My house settled sometime in the late 1970s or early 1980s. The cracks from that settlement are still there. But the settlement stopped decades ago. The cracks are scars from ancient history. Nothing is still moving.
Historic damage is stable. It looks bad but behaves well. You can seal it, ignore it, or live with it. It won't get worse.
Active Damage
Gary's wall was actively failing. The crack was growing. The bow was increasing. The problem was not historic. It was ongoing. Ignoring it would only make it worse and more expensive to fix.
Active damage requires intervention. The forces causing it haven't stopped. The damage will continue until someone does something.
How To Tell
Time. Monitor for a year. If nothing changes through all four seasons, historic. If things get progressively worse, active. There's no shortcut. You need data over time.
This is why I push everyone to monitor instead of guessing. My five years of stable data proves historic. Gary's three months of progressive data proved active. The monitoring made the difference clear.
What Causes Ongoing Movement
Understanding causes helps predict behavior.
Water Problems
Gary's wall was being pushed by saturated soil. We'd had unusually wet weather. His drainage wasn't great. The water accumulated, the soil expanded, and the wall started losing the fight. Water problems don't fix themselves. They usually get worse.
Soil Conditions
My friend Dave in Texas deals with expansive clay that never stays the same. Wet season, dry season, the soil moves constantly. Active movement from soil is hard to stop without addressing the soil itself.
Tree Roots
Growing trees continue to affect soil moisture. Gary's neighbor had a willow tree that kept growing and kept causing problems. The movement continued until the tree was removed. Then the soil had to stabilize, which caused its own issues.
Inadequate Original Design
Some foundations were undersized for their soil conditions. If the original design was barely adequate, ongoing stress eventually causes progressive failure. This was probably part of Gary's problem. His 1980s foundation wasn't built for the soil pressure it eventually faced.
When I Would Call Someone
My foundation is stable. But here's what would trigger a call.
Any Horizontal Crack
If I ever saw a horizontal crack in my basement wall, I'd be calling an engineer the same day. Horizontal cracks mean the wall is failing to resist lateral pressure. That's serious.
Gary had a horizontal crack. I saw it and knew immediately it wasn't like my vertical shrinkage cracks. Different animal entirely.
Detectable Wall Bow
If my level showed any wall bow, or if I could see a curve when sighting down the wall. Even an inch of bow is concerning. Gary's inch and a half required $8,400 in wall anchors.
Progressive Measurements
If my monitoring showed cracks growing, widening, or extending. Any progressive trend over multiple measurement periods. That's what Gary's data showed. Growth over time means active failure.
Multiple Symptoms Appearing
If I started seeing sticking doors, new gaps, drywall cracks, and floor changes all at once. Single symptoms might have innocent explanations. Multiple symptoms forming a pattern suggests coordinated foundation movement.
Gut Feeling
If something felt wrong and I was losing sleep over it. The $350 for an engineer's opinion is worth it just for peace of mind. I did this once. The engineer confirmed my foundation was fine. Best money I spent that year.