When to call a structural engineer about your foundation
Most hairline cracks can wait. A few signs cannot. Here is where the line sits, and what you get for the visit.
Call a licensed structural engineer when a wall or floor is moving, not just cracked. A crack that stays the same width for a year is a record. A crack that grows, a wall that leans more each season, or a floor that slopes toward one corner is a case.
This page is about when to make the call. It is not a way to diagnose your house from a chair, and nothing here is a repair you plan yourself.
Which signs mean you should call?
Some signs justify a call soon. Others justify a note in your calendar. The table splits them.
| What you see | Usual next step |
|---|---|
| Hairline crack, same width after months | Photograph, measure, keep watching |
| Crack wider at one end, or growing | Call an engineer |
| Wall bowing or leaning inward | Call an engineer |
| Horizontal crack along a block wall | Call an engineer |
| Doors and windows suddenly sticking | Measure, then call if it keeps changing |
| Floor sloping or sagging | Call if it is new or getting worse |
A horizontal crack deserves more respect than a vertical one. It often means soil is pushing on the wall. The page on a bowing basement wall explains what that pressure looks like.
What does a structural engineer actually do?
The engineer looks at the wall, the cracks, the floor above and the ground outside. They measure, take notes and often photograph everything. Then they write down what they think is happening and what, if anything, should be done.
That written finding is the product. It is what you hand to a contractor, a lender or a building department. A verbal "it looks fine" is not worth much once the next owner asks.
Why an independent engineer matters
Many foundation companies offer a free inspection. That is a sales visit, and the person doing it is paid to find work. It can still be useful as information. It is a poor substitute for an opinion from someone with nothing to sell.
Look for a licensed structural engineer who does not install repairs. Ask whether they are licensed in your state. Then compare any quote against their written report, not the other way around.
What not to do while you wait
Do not dig beside a leaning wall to take a look. Do not push it back, jack it or load it with new weight. Soil you remove may be the thing holding it up.
Do not sign a repair contract in the same visit as the first inspection. A good fix will still be a good fix next week.
How to prepare for the visit
Photograph each crack with a coin or ruler beside it. Date the photos. Mark the ends of each crack in pencil with the date, so any growth shows. Write down when you first noticed it and whether it changes after rain.
Rules, permits and engineering requirements are set locally and vary by state. Your building department can tell you what applies where you live.
When the report arrives, the page on how to read a foundation engineer's report walks through what each section is telling you.
Frequently asked questions
When should I call a structural engineer about a foundation crack?
When the crack is growing, wider at one end, horizontal, or paired with a leaning wall or a sloping floor. A stable hairline crack can usually be watched first.
What does a structural engineer do during a foundation inspection?
They examine the foundation, cracks, floors and drainage, take measurements, and write a report on what is likely happening and what, if anything, should be done.
Is a free foundation inspection from a repair company enough?
It can give you information, but the inspector is paid to find work. An independent licensed structural engineer has nothing to sell, which is the point of hiring one.
Do I need an engineer for a hairline crack?
Often not at first. Photograph it, measure it and keep a dated record. Call if it widens, lengthens or starts to line up with other signs of movement.
Should I sign a repair contract right after the inspection?
No. Get a written finding from an independent engineer first, then compare quotes against it.
Sources
What this page explains is based on these official sources. If you check one and it does not match what you read here, send it to us and the article gets corrected.