Has It Moved, or Is It Still Moving? The Missouri Floor Question
These are two different problems with two different answers, and almost nobody asks which one they have before spending money on a floor.
The two cases
It has moved. A house that settled decades ago has found its level. It may sit visibly out of level — doors that swing, a marble that rolls — but it has stopped traveling. That is a one-off leveling job followed by any material you like.
It is still moving. A house on graded clay fill that has been through only a handful of seasons is still working through its first cycles. That is a material decision rather than a preparation one: choose something that tolerates movement, because leveling it perfectly today does not keep it level.
Age is the best clue you have
Nothing tells you outright, but when the house was built is the strongest available signal. Missouri gives an unusually wide spread:
- St. Louis — a 1938 median, 57.9% of it built before 1940. Ninety years of cycles have already happened.
- St. Joseph 1962, Independence 1967, Kansas City 1969 — largely settled, with a prewar core that is very settled indeed.
- Blue Springs and St. Charles 1986, Columbia 1993, Lee’s Summit 1994 — mixed, and worth looking at rather than assuming.
- O’Fallon — a 2000 median and 0.8% pre-1940. Young ground.
Three checks anyone can do
- The straightedge. A ten-foot straightedge and a tape measure tell you how far out of flat the floor is today. Write the number down — it is the number every flooring warranty is written around.
- The season. If doors bind in spring and swing freely in autumn, something is moving with the moisture. If they have been exactly the same for fifteen years, it is not.
- The history. Ask how long the house has stood and whether the lot was cut and filled. A builder’s grading plan is a better predictor than any single measurement.
What each answer buys you
Settled: level the floor properly once, then lay whatever you want, including tile and stone. Still moving: prefer a floating floor, and if you want tile anyway, specify an uncoupling membrane and a genuinely flat substrate and accept that both cost money.
Common questions
Can a floor be both?
Frequently — an older house with a newer addition is two different structures on the same lot, and the join between them is where movement shows first.
How long until new ground settles?
There is no clean number, and anyone offering one is guessing. What is reliable is that the first few seasonal cycles do the most visible work.