We get this call every summer. A cabinet door or an interior door that behaved all winter starts catching against its frame once the humidity climbs. Nothing is broken. The wood is breathing.
What is actually happening
Wood is hygroscopic: it exchanges moisture with the air around it until the two reach equilibrium. When the surrounding air is humid, wood absorbs moisture and swells. When the air dries out, it releases moisture and shrinks. This never stops, for the entire life of the piece.
The important detail is direction. Wood moves very little along its length – a board barely changes end to end. It moves substantially across its width, and it moves differently depending on how the board was cut from the log. A flat-sawn board can change width noticeably between a dry season and a wet one. That is why a door gets tighter side to side but not top to bottom.
Why Southwest Florida is a hard case
The swing here is not just seasonal, it is architectural. A house that runs air conditioning heavily is dry inside while the air just outside the door is saturated. Every time a slider opens, the interior moisture level moves. Wood in that house is chasing a target that keeps shifting.
What good carpentry does about it
Nothing stops wood from moving. Good work accommodates it:
- Acclimation. Material sits in the house for several days before it is cut, so it is already near the moisture level it will live at.
- Floating panels. A raised panel door is built so the center panel sits loose in its grooves. It expands and contracts freely while the frame around it holds the dimensions. A panel glued in place will crack itself.
- Honest reveals. We set gaps around doors and drawer fronts with the wet season in mind, not the day of installation.
- Finish on all six sides. Finishing only the visible face lets the back absorb moisture at a different rate, and the piece cups.
When to call someone
Seasonal sticking that comes and goes is normal. What is not normal: a door that never closes properly in any season, visible cupping across a panel, a joint that has opened and stayed open, or a gap that grows year over year. Those point to a construction problem rather than a weather one, and they are worth looking at.
