Introducing the Soffit Vent by Moisture Flow® 


Why Is The Soffit Vent System So Important?

The Soffit Vent System solves a long-standing problem in the building industry: the damage caused by venting a bathroom exhaust fan to a soffit.  The Soffit Vent System is an adapted termination that now gives builders and homeowner the ability to vent bathroom exhaust fans through the soffit without running the risk of the exhausted air from going back into the attic.  It safely and effectively allows venting a bathroom exhaust fan to a soffit.  It is a revolutionary alternative to venting through the roof. Cutting into the roof’s sheathing can, and often does, create roof leaks and catastrophic water damage.  Venting through the roof can also void a roof warranty. The Soffit Vent System is code compliant under The International Code Council (ICC) and the International Residential Code (IRC).

How Does The Soffit Vent System Work?

By effectively displaces exhausted air from a bathroom exhaust fan, through a soffit, and out of the soffit’s passive air stream.  Effective displacement subscribes to the removal of exhausted air away from the assembly and preventing re-entry.

Our Soffit Vent has multiple points of egress for bulk moisture, should moisture condense inside of the vent.  These points of egress also prevent reentry of moisture into the attic and prevent moisture build up inside of the vent.  The vent can be used on soffits ranging from 8” to 48” long.

Unique in its function and design, the Soffit Vent System is the only product on the market that takes the exhausting air out of the soffit’s passive air stream.  The soffit is designed to take in air, helping to ventilate the roof deck.  Subsequently, any air vented within the soffit’s air stream will end up back in the attic.  This promotes moisture problems and mold growth.  For these reasons – in the residential energy efficiency industry – venting a bath fan into the soffit is considered the least ideal place for venting and is oftentimes utilized as a last resort.  This soffit vent termination is truly an industry first.  It not only gives builders a real, effective, and viable alternative to venting to the roof or gable wall, it is now the best way to vent a bath fan. 

What Do Soffits Do?

Soffits serves both an aesthetic and functional purpose for a building’s roofing system.  It’s the skin that covers your eaves.  Without it, you would expose your rafters.  Functionally, it is the roof’s passive air intake for ventilation

Consequences of Improper Venting

An attic is not part of the living space, is “out of sight out of mind,” with inspections few and far between. Once mold is visible on the ceilings and walls beneath the attic, then the mold is already in an advanced stage of growth. In the USA, homeowners spend over $15 billion annually on remediation caused by attic mold and moisture damage. The health-care costs from mold contamination and the loss of business productivity exceed half a trillion dollars annually.  Mold contamination also affects domestic animals, which can cost homeowners thousands of dollars in medical treatment.

Bath Fan Venting Causes of Attic Mold and Moisture

Four most common causes are: (1) The bathroom exhaust fan or the fan’s transition duct vents directly into the attic. (2) Venting directly into the soffit. (3) deterioration of a roof vent exposed to the climatic conditions that are connected to the bathroom exhaust fan.  (4) Gable Vents actually compromise the effectiveness of removing the heat and humidity and causes the formation of mold and condensation in the attic. 

The Soffit Vent System eliminates all of these risk factors.                                                                                                                                                                                                                        

                                                    Ideal Consumer –Anyone with a soffit.

The Soffit Vent System is perfect for national home builders and contractors in the home improvement industry, the 136 million existing homes, 5.6 million commercial buildings, and the 50 million do-it-yourself (DIY) homeowners in the USA.  


The Soffit Vent comes with a standard, no questions asked, lifetime warranty.