Roof Fan Size

Attic fan size calculation.

Roof fan size.

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. Hvls fans like these are sold by the big ass fan company and similar brands that target the industrial fan market. You will want to check your fan to ensure that its cfm rating is anywhere between 1 600 and 4 500. 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.

When it comes to the right size of ceiling fan for your space you need to keep proportions in mind. Attic vent fans are commonly rated from 800 to 1 600 cfm making one fans suitable for attics of up to around 2 200 square feet. You may have seen an extremely large diameter ceiling fan in an airport convention center or large industrial complex. Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute.

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. Our stylish powder coated steel 30 watt fan will effectively ventilate up to 2500 sq. 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. Use the chart below as an attic vent fan cfm calculator.

The formula above gives an approximate value of the cfm needed for an attic fan. 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. And beyond we even offer fans with an expansive 99 inch blade span. This is the least expensive high quality fan feature for feature available.

Attic fan size cfm 0 7 x sq ft area of the attic formula 1 the size of an attic fan is calculated in terms of cfm. 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. Of attic space at up to 1550 cfm. In terms of sizing your ceiling fan for your bedroom there are two common size options for bedrooms.