Steps are the first thing to move and the most dangerous when they do. A rocking tread or an uneven rise is a fall waiting to happen, and it is almost always the base or a missing clip rather than the blocks themselves.
A rocking step is a base problem, not a block problem
Steps carry more load per square foot than any other part of a paved surface and usually sit on the least base. Most sets we take apart were built on a few inches of screening straight onto clay, with no drainage behind the risers and no clips holding the courses together.
Water gets in, freezes, lifts the top course, and the rise between the treads goes uneven. The rebuild is not complicated, it is just done properly: a real base, drainage behind, and each course pinned or glued to the one below.
We record the height of each tread before anything comes apart, because the finished flight has to match the door sill at the top.
Dismantle and sort
Blocks come off course by course and are cleaned and stacked, so the same faces go back to the front.
Base and drain
Compacted base under the bottom course, clear stone behind the risers, and a path for water to leave rather than sit.
Rebuild and pin
Courses rebuilt to even rises, pinned or adhered where the pattern needs it, and the treads set with a slight fall.
Movement Or Rise
A step that rocks, and one out of rhythm
The four pages here split on which of two problems you have. A tread that moves under weight is a bedding failure, and packing something under the low corner buys one winter before it is back.
A flight where the rises differ is a geometry problem, and it catches people who have used that entrance for years, because everybody climbs by feel after the first two treads. Both get dismantled and rebuilt rather than shimmed, and every rise is measured rather than eyeballed. A landing is the worst place for either, because that is where people turn with their hands full.
Not always. If the rest of the flight measures even and the base under it is sound, a single course can be lifted and re-bedded.
The landing has settled away from the house, usually because backfill against the foundation was never properly compacted. It gets re-based and brought up.
Yes. People climb steps by feel, and a rise that differs by more than about six millimetres from its neighbours is what catches a toe.
Usually most of them. Caps and treads take the wear, so those are the ones we sometimes replace while the flight is apart.
Twenty years or more when there is a real base and drainage behind. The ones we take apart after five years never had either.
We work around existing railings and reset posts that are bedded in the steps, but new railing supply and code work goes to a railing contractor.
