Where Indoor Moisture Comes From

• People
• Bathroom
• Kitchen
• Laundry
• Humidifiers
• Plants, pets, water features
• Fuel-burning appliances
• Basement and renovation

Indoor moisture comes from the people in the home and from what they do. Some sources are obvious. Others hide. Walk the home with this list and tick what applies.

§People

Everyone breathes moisture all day and night. More people, or more hours at home, means more moisture. A small bedroom with two people and a closed door is a strong overnight source.

§Bathroom

• Long hot showers and baths
• Wet towels hung in the room
• Missing, weak, broken, or short-run exhaust fans
• Fans that vent into an attic or ceiling space instead of outdoors

§Kitchen

• Boiling, simmering, steaming, dishwashing
• Recirculating range hoods that filter grease and odour but do not remove moisture from the house
• Cooking with lids off; kettles left steaming

§Laundry

• Clothes drying on racks or radiators indoors
• Dryers that do not vent outdoors, or vents that are crushed, disconnected, lint-clogged, or stuck shut outside

§Humidifiers

• Portable units in bedrooms or living rooms
• Whole-home furnace humidifiers set too high or never adjusted as weather changes
• Units added for a cold or dry skin and then left running

§Plants, pets, water features

Many houseplants (especially clustered near windows), open aquariums or terrariums, and large indoor water features add vapour. Pet water bowls are usually small by comparison.

§Fuel-burning appliances

Unvented gas or kerosene heaters release water vapour (and other combustion gases) into the room. Long use of gas cooking without a ducted hood adds moisture too. Suspected venting problems, soot, rust, or water around an appliance vent need a qualified technician — do not diagnose combustion venting yourself.

§Basement and renovation

A damp basement can feed the whole house. Watch for musty smell, damp patches, white powder on concrete, rust near the floor, and condensation on cold pipes. New construction and renovations can also hold building moisture for a while after work finishes.

An audit is not a diagnosis of building failure. It is a map of what you can turn down, vent, or change first.

Originally published at https://dry-glass-notes.surge.sh/articles/indoor-moisture-sources.html (AI-assisted, sources cited). If this helped, zaps go to hollisvarrow3753@coinos.io.