Are ridge vents better than other attic vents, and is ridge venting really better?
Why the ridge is the best place to exhaust
Hot air rises, so the warmest, most humid air in an attic gathers at the peak. A vent located there uses that natural lift, called the stack effect, to keep air moving even on still days. Wind blowing across a baffled ridge vent also creates lower pressure over the opening, which helps draw air out. Box vents installed a few feet down the slope leave a pocket of hot air above them.
Even coverage
Spot vents pull hard from the bays right around them and weakly from the bays in between. A continuous ridge vent pulls from every bay along its length, so when soffit intake is also continuous, air washes the underside of the decking from eave to peak. That even flow keeps the decking dry and avoids hot spots that age shingles faster.
Other practical advantages
- No moving parts and no power, unlike turbines and fans.
- Fewer holes cut through the field of the roof, so fewer flashing points to fail.
- A low, clean roof line, which matters to many HOAs.
When ridge venting is not the better choice
Hip roofs with short ridges, roofs with no way to add intake, and homes converting to a sealed spray foam attic are the main exceptions. On a hip roof, a combination of ridge and hip vents or a row of box vents may be needed to reach the required vent area. For the head to head comparison, read ridge vent vs box vents, and for the overall system, roof ventilation basics.