Ratio Of Soffit Vents To Roof Vents

Choosing round soffit vents for.

Ratio of soffit vents to roof vents.

For example our v 600 products have 20 sq. Resin circular mini wall louver soffit vent in white 6 pack model rlsc2 view the master flow intake vents 9 28 9 28. The ratio of soffit intake to roof outlet should be at least 2 1 to avoid unnecessary these heat losses from the building. As a homeowner it is important that you review the soffit areas of the home for soffit vents.

Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space. Master flow 2 in. In net free vent area nfva in the soffit intake than at the ridge. Determine the amount of intake venting required.

But the ratio of intake air to outlet air is of critical importance too. For example if you use 16 inch by 8 inch soffit vents each vent is 128 square inches. To balance this you need 2 soffit eave intake vents of approximately 10 sq. More ways to filter.

Where eave or cornice vents note. These specialty vents do not affect the. For the number of soffit vents in the example divide 8 square feet of ventilation needed by 0 5 for the number of rectangular vents required 16 in the example. A serious error is a roof outlet vent net free area that exceeds the air inlets at lower roof edges or eaves.

Master flow 15 amerimax home products 1 deflect o 1 gibraltar building products 1 mounting position. An equal or greater amount of vent opening sq. Divide this by 144 to calculate how many square feet each vent is. For roofs with a 7 12 to 10 12 roof pitch you may want to add 20 percent more cfm.

One square foot equals 144 square inches so the standard 16 inch by 8 inch soffit vent is 0 89 square feet. And for roofs 11 12 pitch and higher add 30 more cfm to handle the larger volume of attic space. P er lineal foot 1 2of 20 in each overhang. Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge.

Rafter vents or insulation baffles install in any rafter space to create narrow gaps that direct fresh air from the soffit vents to the peak of the roof. An important part of installing any system of ventilation into your roof system is to make sure that there is a point of entry and a point of exit for airflow.