Cabinets under kitchen and bathroom sinks are easy to forget. The supply lines, shutoff valves and drain pipes sit in a tight, dark space, and a slow drip can run for a while before anyone sees the signs. Most slow leaks do not look dramatic. They show up as a faint water ring, a cabinet floor that feels soft, a small puddle that dries overnight, or a musty smell that comes and goes.
This is a calm, practical routine for checking those spaces and for keeping a short record of what you find. It is general home maintenance guidance. It does not replace a licensed plumber, and in a rented home the first call usually goes to the landlord or property manager.
A monthly walk-through
Pick a fixed day, such as the first weekend of each month, and follow the same order every time. Open the cabinet doors, move anything that blocks the back wall, and use a flashlight. Keep a stack of dry paper towels nearby.
Start with the floor. Wipe it dry, then lay a paper towel flat on the bottom of the cabinet and check it after a few minutes. Press along the base panel and the floor for softness or swelling. Next, look at the supply lines, the flexible hoses that run from the wall or floor up to the faucet and toilet. Note any bulging, cracking, or rust at the fittings.
Then check the shutoff valves. Turn each one slightly and back to confirm it still moves. If a valve is stiff, or drips when you move it, write that down and leave it alone. Forcing an old valve can make a small problem worse, so the safer step is a plumber visit.
Look at the trap, the curved pipe beneath the drain, and every joint you can reach. Note any drips, crusty residue, or damp spots. If a dishwasher or water filter shares the cabinet, check its hoses and housing too. Finally, pause and notice the smell. A musty odor is worth recording even when you cannot see anything wrong.
Keep a simple log
A short written record turns a vague impression into something you can act on. Use a notebook or a shared note on your phone, and record the date, the location, what you saw or smelled, whether you took a photo, what you did, who you contacted, and when you plan to check again. Dated entries make it easier to tell whether a spot is getting worse, staying the same, or clearing up after a repair.
The log also helps when someone else needs the history. A plumber can see at a glance when a stain first appeared, and a family member or landlord who joins the routine can pick up where you left off. If a repair is quoted, the log shows what was noticed before the visit.
If one person in the household handles the monthly check for an older relative, a planned break can keep the routine steady. Some families look for family caregiver respite in St. Louis that fits your calendar when they set up a rotation.
Records matter beyond the home
This week The Guardian reported that Senator Ron Wyden has opened an investigation into evidence that the health secretary, Robert F Kennedy Jr, "unlawfully lied" during his 2025 confirmation hearings. The report was written by Michelle R Smith, and the Guardian story on the Senate inquiry sets out the details as reported. This article does not weigh in on that inquiry. The point for a household is narrower. A written, dated account is easier to check than a memory, and that is true for a cabinet floor as much as for anything else that needs a clear record.
When to call a professional
Call a licensed plumber if you find active dripping, a soft cabinet floor, a valve that will not turn or seal, or a smell that persists after the area has dried. Do not wait for a stain to grow before making the call. Bring your log, since a few weeks of dated notes often makes the visit faster and the repair clearer for everyone involved.