Can I Have Both a Power Fan and a Ridge Vent System on My Roof?

When the hot days of summer are upon us, this is a question our customers frequently ask us: Can a power fan and ridge vent coexist?.

Having both a power vent and ridge vent installed on your roof can short circuit the attic ventilation system. When the power vent goes on, it can actually pull air from the ridge vent, which can cause an imbalance of airflow along the underside of the roof deck. When the power vent goes off, it acts like a roof louver (an opening on the roof without a motor. In this case, the ridge vent pulls its intake air from the power fan which can lead to “weather infiltration” and poor ventilation along the underside of the roof deck.

In most homes, it is typically best to have only the ridge vent and remove the fan, as described above, they don’t work well together.

If you have a hip roof with very little ridge, a power fan with both a thermostat and humidistat (for both temperature and humidity) should be installed, with no ridge vent.

With any attic ventilation system, the attic can be 20 degrees hotter than outside. Attic ventilation should protect the roof sheathing, insulation, and shingles from temperature and moisture extremes. However, many variables can affect the attic temperature, such as shingle color (black shingles absorb more heat and can make the attic hotter than white shingles). Other factors are the geographical location, sun intensity, orientation of the primary roof plane, and amount of total ventilation.

If you feel your home is warmer than it should be in the summer, Emmons Roofing & Siding can install a roof ventilation system – contact us today.

If you’re located in the Greater Philadelphia Area, South Jersey, or at the Jersey Shore, contact Emmons today for a free quote. Contact Us