Why Did The Outer Walls Of The Bathroom Exhaust Rust?

The presence of rust on exterior walls around the bathroom exhaust can be attributed to moisture accumulation. When hot, humid, a bath fan can exhaust through the roof or out a sidewall of your home. Exhausting bath exhaust out a roof is the safest and best method to ensure all surfaces are properly ventilated.

The most common bathroom venting option is when the exhaust fan is mounted on it, eliminating the need for lengthy ducts. A bathroom fan is installed on the ceiling while the exhaust vent leads to the outside. If the vent goes through several twists and turns before it reaches the outside, as long as these two key elements are present, you are using the ceiling-to-wall venting option. Brown liquid dripping from your fan is bad, but if there is a red/orange tint to the brown liquid, this can indicate corrosion somewhere along your bathroom.

To identify the type, cause, and cure of stains on building exterior surfaces, it is important to discuss each stain by color, type, cause, and cure. For proper bathroom ventilation, it is best to run the ductwork from the bathroom exhaust fan vertically through the roof or out the side gable wall. Venting a bathroom fan through an exterior wall requires cutting a 3″ exhaust fan and keeping it running for 30 minutes afterwards.

If you don’t connect a vent to the outside of the house, moisture will condense back into water in the attic, creating mold and water damage. Bath fans should be vented outside to prevent moisture from condensing on framing and sheathing, causing mold and rot. Improperly sized or incorrectly installed bathroom exhaust fans can lead to humidity build up, rot, and mold growth.