A mudroom or entry closet is often the first place St. Louis weather comes indoors. Rain soaks jackets, melting snow runs off boots, and umbrellas drip onto the same floor for hours. Much of that water eventually becomes humidity in the room, and it can build up in a space that gets less air movement than the rest of the house.
Why the entry stays damp
Entry spaces collect moisture from several sources at once. Wet outerwear hangs in a small area, the door to the garage or outside lets in cold, humid air, and tile or vinyl floors hold surface water instead of soaking it up. Over time, that moisture can move into nearby walls, baseboards and closet shelves.
Check the door first
Start with the exterior door, since it is the most common route for water and humid air.
- Look at the threshold for gaps, cracks or loose caulk where water can run underneath.
- Check the door sweep or bottom seal for wear. A worn sweep lets rain and humid air pass straight through.
- Feel for drafts with your hand on a windy day, and note where air moves in around the frame.
- Look at the weatherstripping on the sides and top of the door for cracks or flattened spots.
- Check the exterior step or landing. If water pools there, it can run toward the door.
Look for signs in the room
Moisture problems in a mudroom often show up on the surfaces near the floor and the wall behind the coat hooks. Look for these signs:
- Staining or lifting on the bottom of baseboards or trim near the door.
- Soft spots or a musty smell in the flooring under the mat or rug.
- Dark marks on the back of a closet wall or on the shelves above the coats.
- Grout lines that stay dark or damp long after the floor has dried.
- Doors or drawers near the entry that stick more often during wet weather.
If you find staining or a soft floor, pull back the mat and let the area dry completely. Then trace the source before you close the space back up. Do not paint over a stain until you know it is dry.
Reduce the moisture that comes in
Small habits make a noticeable difference in a busy entry.
- Set a tray or mat by the door that catches melting snow and rain from boots, and empty it after each storm.
- Hang wet coats on hooks spaced apart so air can reach the fabric, instead of stacking them on top of each other.
- Keep umbrellas in a stand that lets them drain, away from the floor covering.
- Take wet shoes off in a spot with a hard surface, and move them to a dry area once they are dry enough to stop dripping.
- Wipe the floor after heavy wet weather rather than leaving water to sit on tile or wood.
Improve airflow in the space
A mudroom with no air movement will hold humidity longer than an open hallway. If the room is closed in, consider a few simple changes. Leave the closet door cracked after a wet day so air can circulate. If the room has a vent, make sure it is not blocked by a coat rack or stored bags. If the entry has no vent at all, a small fan on a timer can help move air during the hours when people come and go most.
Measure the room's humidity
Instead of guessing, place a hygrometer, which is a simple device that reads relative humidity, in the entry at about head height and away from the door. Compare its reading with one taken in a living room. A large gap between the two often points to the entry as the source of extra moisture. Take readings on a dry day and on a rainy day so you can see how the room responds to weather. Keep the device away from direct sunlight, heat registers and the exterior door, since those spots can give misleading readings.
When to call for help
Most mudroom moisture comes from weather and worn seals, and you can address both yourself. If you see water coming from under the threshold during steady rain, notice a floor that feels soft, or find staining that keeps returning after you have dried the area, a local contractor or inspector who works in St. Louis homes can look at the door frame, subfloor and drainage around the entry. Describe what you have seen, when it happens and how long the area stays damp. That information helps whoever comes out decide what to check first.