How Many Square Feet Per Roof Turbine

This will give you square inches instead of square feet.

How many square feet per roof turbine.

Build your roof empowers you to select each layer and component that goes into your total protection roofing system so that you get the roof you want to protect your home. 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. A small 12 inch diameter turbine vent with a constant wind speed of 5 miles per hour mph can remove 347 cubic feet of air per minute cfm from the attic space. Take this number and divide it by three hundred.

We want to share those questions and answers with you. Flat roof vents have no moving parts to break or squeak but don t vent as much air as wind driven vents. Depending upon the diameter of the vents and the wind speed outdoors the turbines can expel vast quantities of humid air before it becomes a problem. Although more vent is generally better replacing a turbine vent with a standard flat vent is acceptable as long the vent is big enough for the square footage of the attic space.

Thus if your attic is 450 square feet you need roof vents equaling 3 square feet. 1 square foot of ventilation for every 300 square feet of space for pitched roofs with vapor barriers. 30 lineal feet required. There are also gable and roof fans which actively pull the hot air out of the attic.

First find out the square footage of your attic and sketch it onto the graph paper. 1 100 square inches of intake net free area needed. 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. For example a 6 by 12 inch soffit vent has 72 square inches which when divided by 144 results in a 0 5 square.

Now take the square footage number and multiply it by 144. The next step is to select a suitable exhaust vent and intake vent that fits the roof design for best performance and best aesthetics. This is accomplished by taking the square feet recommended and multiplying by 144. Say the contractor is standing in front of a house that has an attic with 2 200 square feet.

Then divide that calculation by 144 to convert the square inches to square feet. The quotient is the amount of ventilation you will need for your attic. Because vents are rated in square inches you need to convert the square feet required to square inches. Thousands of cfm per hour.

2 200 2 1 100 square inches of exhaust net free area needed. Thus 6 66 divided by 2 3 33 square feet of attic ventilation for intake and 3 33 square feet of attic ventilation for exhaust.