Ridge vents are a very efficient form of static exhaust vents.
They are installed over a slot that is cut in the ridges of roofs to ex- haust the attic space air flowing from ventilating intake soffits at the eaves, as shown in the Soffit-to-Ridge-Vent Ventilation image.
The ridge vents that we install incorporate an internal baffle that allows air to escape from the attic space. We use special installation procedures that prevents wind driven rain or snow from entering attic areas, regardless of the wind direction and force.
We install two styles of ridge vents: shingle vent, with ridge cap covers, and metal ridge vents, shown in the adjacent image.
NOTE:We will always install shingle vents on roofs that don't have adequate ventilation, including houses with gable end wall vents.
The majority of our customers prefer shingle vents, because of how attractive a roof finished with shingle caps appears.
When we determine that an existing exhaust ventilation systems is inad- equate and/or a ridge vent can't be installed, because of a roof's design, we will recommend vents that should be installed to satisfy the minimum requirements, which is: the total ventilation area provision must equal 1/300 times the attic area.
The type of ventilation that you want installed is up to you; however, we will advise you of the impact of not having a proper ventilation system will have on the shingle manufacturer's warranty.
Soffits vents are in- stalled under the eaves of a roof. Air that is used to cool the roof is drawn into the soffit vents and exhausted via ridge vents or other vents.
Vented drip-edge can be added to an existing roof to provide in-take ventilation, where ventilating soffit vents are not installed.
They are installed at the eaves in place of conventional drip-edge.
Edge vents are used to provide in-take vent- ilation for homes with little or no overhang.
They are roof-top in- stalled vents that can supplement existing soffit or undereave vents.
A single 4 foot length provides 9 square inches of net free area per linear foot to balance with ridge vent.
Insufficient attic ventilation can lead to moisture problems during Winter and decreased energy efficiency during Summers.
In Winter, adequate roof ventilation can minimize the formation of ice dams and help reduce heating bills.
In Summer, a properly installed roof ventilation system keeps the roofs cooler by exhausting hot air from attic spaces, extending the life of the shingles, by preventing them from drying-out over time from exposure to excessive heat.
Ventilation exhausts any moist attic air that could condense, potentially causing wood damage and allow mold or mildew to form, which could affect your family's health.
Ventilation also helps reduce the formation of ice dams at the roof eaves. Ice dams prevents melt water from running off the roof.
Roof louvres or roof pots are another popular style of exhaust vents. Roof louvers are instal- led at equally spaced intervals, near the ridges.
They are available in round, square and slanted-top configurations. They provide a continuous flow of most of the underside of the sheathing, albeit not a very uniform flow.
Because of their small, individual exhaust areas, several vents may be needed to satisfy the recommended ventilation area.
Gable wall louvres are installed in the gable ends of a house. They are installed more for decorative pur- poses and are not effective ventilators.
Cupolas are aform of static vents. They are decorative vents that straddle the ridge of a roof and are installed over a hole that is cut in the ridge of a roof.
An alternate in-take ventilation system that home owners can install are disk inserts.
They are installed in holes bored in the un-ventilated soffits.
The quantity of disks can be large, because their combined ventilation area must equal 1/300 times the attic area to be ventilated to be ef- fective. The area of one disk is only about 10 in2.
Wind driven turbine vents employ a series of specially shaped vanes that spin cre- ating a negative pres- sure that sucks the air from the attic. They require a wind velocity of at least 5 mph to be effective. They act as static vents, when not spinning. Like static vents, they must be installed equally spaced, near the ridge to prevent hot spots from developing in the roof.
Power vents are similar to wind turbines, except that their rotating vanes are driven by a high efficiency motor and controlled by a thermostat and/or a humistat, to exhaust air from attics.
Depending on theirdesign, power vents can move as much as 1500 cubic feet of air per minute. For optimum performance, multiple power vents should be installed. They are especially effective on hip roofs where unpowered ventilation systems are not.
Electric-powered attic vents use a thermostat to fight heat and a humidistat to help prevent moisture buildup inside the attic. Featuring a low-profile dome, the power roof vent is unobtrusive when installed on the roof face slanting away from the front of your home. It's an efficient option to replace wind driven turbines already in place.
Exhaut fans are used to draw air into a house from the outside and exhaust hot air. The fan and it's shuttered assembly is mounted in the ceiling of, usually the upstairs hallway, with it's output into an attic space that is vented. The principle function of a whole house fan is to help reduce the cooling load on the home's air conditioning system.
Intake booster vents promote greater airflow through a ventilation system by forcing supplemental air into the attic space and out through existing exhaust vents. They are installed near the eaves. They do not replace the necessity for soffit vents. Some versions of these vents are solar powered and do not require any power from the electrical system or an electrician to install them.
Booster exhaust vents install from inside the attic against the underside opening of standard roof vents up to 11 sq. in. They boost ventilation by over 3 times that of passive roof vents, helping to keep the upper roof deck below 32(F) during below freezing weather.
They are available in various sizes and designs. Their main problem is that they are high maintenance. And, they can become a home for birds, bats and even squirrels, when their protective screen is compromised.