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Attic Moisture Sources

Attic moisture sources can be difficult to diagnose.  The sources can range from framing voids, compromised ceiling vapor barrier, electrical or plumbing penetrations, attic hatches or the ever increasing volume of recessed lighting fixtures.  One of the most common attic moisture source is something that is quite easy to identify: bathroom exhaust fan vent hoses.  All too often these exhaust mechanisms are poorly installed or improperly vented to the outside.  Thus creating a significant source of heat & moisture that is introduced to the Attic space with each shower and bath use.

Take a look at the photo below.  You can clearly see that there are 2 individual bath fan vent hoses that are sharing a single exhaust vent.  Neither looks properly fastened to the Gooseneck roof exhaust vent and the other is simply pointed at the penetration in the roof sheathing.  Around these hoses you can see the evidence of moisture and the subsequent damage to the wooden trusses and plywood.  The frost that his building on the plywood & nail heads is a direct result of the moisture these hoses are contributing to the Attic space.

The remedy is simple.  Install an individual gooseneck roof exhaust vent for each and every bath fan, clothes dryer and kitchen hood exhaust fan that is exhausted through the attic.  Make sure that the connection at the fan source & roof vent is secure to prevent air leakage.  It is easy to replace older metal pipes with the newer pre-insulated flexible hose that can be cut to length and snaked through the attic to meet your needs.  IDEAL is happy to provide this service to your bath fans during our Attic insulation upgrade services.  Call today for your FREE inspection.

bath fan moisture sources
bath fan moisture sources