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Bathroom Ventilation

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Checking for Proper Bathroom Ventilation

Most home bathrooms are equipped with a ventilation fan that can be used during showers to expel hot moist air from building up in the bathroom.  Have you ever wondered where all that moist air goes?  If not, then you’re not alone.  Alot of times we find that bathroom exhaust fans simply dump that air into the attic.  Now, you’ve got an attic full of moisture and a prime environment for mold growth.  Mold growth on plywood and OSB will actually delaminate and weaken the strength and integrity of the wood.

Below, is a picture of what years of unproperly vented bathroom fans can do to the underside of a roof decking.  In a case such as the one below, the best thing to do is remove the moldy roof decking and replace with new. (After correcting the source of the moisture first!)

Roof Decking Mold


How to Vent Bathroom Exhaust Fans

Now that we’ve established our main source of moisture contributing to the mold in the attic, we need to correct the situation.  It is a pretty simple process which involves cutting a small hole in the roof decking, extending the insulated exhaust tubing to the hole, and attaching it to an exhaust vent on the roof.  (Pictures below)



Proper ventilation of bathroom exhaust fans can save homeowners thousands of dollars in costly roof repairs and mold remediation.  Not to mention, help keep your entire family safe.  For more roof related information, feel free to browse our site or check out our Roofing 101 page!