Roof Fan Size

Attic x 0 7 700 cfm minimum fan rating add an additional 20 cfm x 1 20 if you have a steep roof and 15 cfm x 1 15 for a dark roof.

Roof fan size.

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. You will want to check your fan to ensure that its cfm rating is anywhere between 1 600 and 4 500. This is the least expensive high quality fan feature for feature available. The 537 cfm fan is capable of moving plenty of air through an average sized attic roughly 1 200 square feet.

Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute. If you have a regular sized bedroom of 144 to 225 square feet then a medium ceiling fan with a blade span of 44 to 50 inches will be a great fit. You may have seen an extremely large diameter ceiling fan in an airport convention center or large industrial complex. The formula above gives an approximate value of the cfm needed for an attic fan.

Attic fan size calculation. Of attic space at up to 1550 cfm. 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. Use the chart below as an attic vent fan cfm calculator.

Hvls fans like these are sold by the big ass fan company and similar brands that target the industrial fan market. When it comes to the right size of ceiling fan for your space you need to keep proportions in mind. Ventilation rate of 10 air changes per hour. Our stylish powder coated steel 30 watt fan will effectively ventilate up to 2500 sq.

Proceed to step 2 and use the chart to determine the size and number of solar powered attic ventilation fans required to achieve a min. These are called hvls high volume low speed fans and range anywhere from 12 feet to 24 feet in diameter. Ceiling fans come in a wide range of blade spans from small mini fans with a blade span of 18 inches up to large ceiling fans with a 68 inch blade span. And beyond we even offer fans with an expansive 99 inch blade span.