Have questions about the roof or attic vents? Here's a handy FAQ list that explains what they are and what purpose they serve:
What are roof vents?
Technically, these are any vents that allow air to pass through the attic or roof deck. Of course, many vents are actually installed on the eaves, but a number are directly attached to the roof itself, depending on design. Roof vents are so important to the health of a house that they are typically required by local building codes for any new projects.
What do they do?
Vents have a very important job. They allow stale, or moist air to pass out from under a roof. Without vents, warm air rises through a house until it reaches the room, where it just lingers. The vents allow the air to keep on moving and pass outside.
Why is this important?
These vents help in a couple different ways. By moving warm air outside, they make it easier for air conditioners to do their job and cool down a home. More importantly, they stop humidity problems before they start. As the moist air gathers under the roof, the humidity rises and water starts to condense in the attic and roof deck. This moisture creates numerous problems, from rot and mold to pests.
Don't think that roof vents are unimportant for those who live in dry climates. Since homes are usually well-insulated, the air inside a house typically has enough humidity to cause problems no matter where the house is located.
Are there different kinds of vents?
Yes, there are active and passive vents. Active vents are typically sprouting out of rooftops in conical shapes. These include fan blades that are turned by motor or wind power and pull air out from the attic quickly. Active vents are more suitable for large spaces or very humid areas. Passive vents are simply grates placed into eave panels that allow air to leave on its own.
Do I need to add some roof vents?
More roof vents are not better. If there are too many vents, it'll be difficult to cool the home when summer comes around - plus having too many vents can increase fire dangers or blowouts. If there is ever condensation in an attic area, it's best to call an attic insulation professional and ask them to take a look. A professional will provide an estimate on what types of vents are needed and how much they will cost.
Note: Having sufficient roof venting doesn't mean vents can be ignored. These vents - especially the active versions - can grow clogged with dust, debris, snow or ice. It's a good idea to check on vents once or twice a year to make sure nothing is covering them up.