Flex Duct Cfm Calculator

This online air duct calculator is used to calculate the velocity of air flow feet per minute fpm and feet per second fps through any shaped circle square or rectangle ductulator with either diameter sides or area.

Flex duct cfm calculator. Read friction loss inches of water and duct velocity fpm. Input the required cfm in the box below that. Fpm is velocity in flex duct feet per minute. Metal ductboard flex size by.

Rectangular duct is rounded up to the nearest 1 4 inch. Data is based on straight runs of quietflex non metallic flexible air ducts as tested in accordance with the air diffusion council fd 72r1 test code and in accordance with ashrae 120 1999 method of testing to determine flow resistance of hvac. In wg duct tel. Select the duct type on the pull down menu.

Click calculate and you will see the size of flex duct you need for that room. The flex duct size may be different than the hard duct that runs to that room. Use the online duct calculator see references and calculate the needed flex duct size. Sheet metal duct friction loss calculator.

Read round duct diameter inches and friction loss per 100 of duct inches of water. Enter round duct diameter. Friction loss calculator for flexible ducts. Include fittings in the duct tel enter either.

Enter duct airflow cfm duct velocity fpm duct length and the number of bends. Calculations are for 60 f dry air at sea level from 5 to 3000 cfm approximately standard air which is 0 075lb da ft. Equivalent duct calculator round vs rectangular. Flex duct 05 on most metal duct calculator round metal pipe 06 on most metal duct calculators field duct sizing chart rectangular sheet metal duct 07 on most metal duct calculators.

Friction loss calculator for sheet metal ducts. Enter round duct diameter inches duct airflow cfm duct length and the number of bends. Read duct diameter inches and duct velocity fpm. Friction rate velocity friction rate.

If ashrae 2013 is selected flexible roughness is 0 003 ft when straight and fully stretched tight at 0 compression adjusted at other compressions otherwise the. Enter the desired length of the rectangular duct. Air duct also termed as ductulator is a passage that is used to provide fresh air into rooms buildings etc air ducts may be in circular square and in rectangular shapes. Other hart cooley mobile tools.

Duct cross sectional area air flow rate and air speed are used in calculating the duct size. Cfm 4 cfm 6 cfm 8 cfm 10 cfm 12 60 6x4 60 4x6 90 4x8 120 4x10 150 4x12. Cfm is flow rate in flex duct cubic feet per minute.