Roof Exhaust Vent | Pacific West Roofing


As an experienced commercial and residential roofing contractor with a forty-year history serving the Portland, Oregon area, Pacific West Roofing understands ventilation systems and the roof exhaust vents that are best for our climate and weather.

Residential, Commercial / Industrial Roofing & Ventilation Systems

Different types of buildings–residential, commercial, and industrial–require different ventilation systems to maintain optimum airflow, support HVAC systems, and protect the building and its occupants. While the principle of a balanced intake and exhaust ventilation system is the same, the specific components vary between residential attic ventilation systems and commercial/industrial ventilation.

Intake Vents vs. Exhaust Vents

A complete ventilation system will be comprised of both intake and exhaust vents. The intake vents serve to pull fresh, cooler outside air in, while the exhaust vents work to push warmer, moist air out. When working in concert, the vents create an optimal airflow that prevents the buildup of excessive heat or moisture–two conditions that can lead to roof and/or structural damage.

Active vs. Passive Ventilation

Passive ventilation systems are quite effective and are found in most residential homes. Typically residential ventilation will include soffit vents for intake and either ridge or box vents for exhaust. The vents—both intake and exhaust—are essentially static, with no moving parts, and work together to allow heavier cool air to move into the attic space and push lighter warm air out.

Active ventilation systems, on the other hand, rely on moving parts that actively pull or push air through the intake or exhaust vents. The four common types of active roof vents are turbine, power, and solar-powered vents.

Turbine Roof Exhaust Vents

Turbine vents are non-powered vents that use the natural forces of wind and air pressure to spin. The turbine is comprised of blades, or vanes, that are configured to catch wind and create a rotary motion, which pulls rising hot and humid air out of the attic. This is not a vent style typically used in the western United States and is more common in the eastern part of the country.

Power Roof Exhaust Vents (Roof Exhaust Fans)

Power exhaust vents, aka exhaust fans or roof-mounted attic fans, are installed near the ridgeline or top of the roof and rely on electricity to rotate and draw hot air up and out of the attic. They often have a dual thermostat and humidistat, which is especially important during the wetter winter months when humidity levels rise, and condensation is more likely to form inside poorly vented attic spaces.

Any exhaust vent that requires electricity to run—roof/attic exhaust vents; bathroom, kitchen, and laundry room fans—and must be electrically connected by a licensed electrician.

Solar-Powered Roof Exhaust Vents

Solar-powered roof exhaust vents operate much the same as power vents. While this type of roof vent can be energy efficient, problems may occur if the solar panel is unable to hold a charge long enough to run the vent continuously. Solar-powered vents are also typically not as efficient at moving air and have a much lower CFM (cubic feet per minute) rating than electric-powered exhaust fans or vents.

A NOTE ABOUT POWERED EXHAUST VENTS: Unless the intake and exhaust ventilation are balanced, power exhaust vents and fans–whether electric or solar–can have the adverse effect of drawing air conditioning out of your house, causing your HVAC to work harder and your energy bill to rise.

Furnace Vents and Other Exhaust Vents

Homes with central heating and a furnace will typically have furnace vents coming through the roof that expel combustion gases from your furnace. Other common exhaust vents are kitchen, laundry room, and bathroom vents, which may be on an exterior wall or on the roof, depending on the layout of the home. 

Complete Roofing & Ventilation Systems

Whether residential or commercial roofing, we are always talking about the entire roofing and ventilation system–the two go hand-in-hand. How and where intake and exhaust vents are installed on a roof, as well as the type and the total number of vents needed, depend on a number of factors: the type of roof, the building structure, the type of building—residential, commercial, industrial, etc., and even the climate.

This is why you want to hire only experienced roofing contractors who are well versed in all aspects of roof construction, materials, installation, and roof ventilation systems.

Pacific West Roofing installers, inspectors, and technicians are well-trained, knowledgeable, and experienced commercial roofing contractors. We follow commercial roofing industry best practices on every job. We are also BBB accredited, and we are longstanding members and board members of the Western States Roofing Contractors Association and our local Associated Roofing Contractor of Oregon and SW Washington group.

When you hire Pacific West Roofing, you can rest assured our number one priority is to make sure that your home, commercial or industrial building, and its occupants are protected. 

Contact us today to learn more about our residential and commercial roofing services or schedule your roof inspection. We are located in Hubbard, OR, serving the greater Portland Metro area. Our friendly and knowledgeable office staff is ready to help you.

Portland Roofing Contractor Since 1980

CCB# 169414