Door Opening Force Calculation - Staircase Pressurization
Door Opening Force Calculation - Staircase Pressurization
(OP)
Hi All,
I'm unable to figure out a "PARAMETER" in Door Opening force Calculation. I have the formula from ASHRAE and I can substitute values to find the answer. No problem in it. But there comes a parameter that I could NOT relate where it exactly appears on doors. The measurement "DISTANCE FROM DOOR KNOB TO KNOB SIDE OF THE DOOR" is the one. I was wondering from where to where do I need to measure physically on a door. ASHRAE also suggests that while calculating I can take this value to be 75mm. I'm done with the calculation. I'm trying to justify the assumption of 75mm.
Is it between the knob and the latch that gets engaged into the wall?
Would anyone please help me out to figure it out?
Thanks in advance for the help!
I'm unable to figure out a "PARAMETER" in Door Opening force Calculation. I have the formula from ASHRAE and I can substitute values to find the answer. No problem in it. But there comes a parameter that I could NOT relate where it exactly appears on doors. The measurement "DISTANCE FROM DOOR KNOB TO KNOB SIDE OF THE DOOR" is the one. I was wondering from where to where do I need to measure physically on a door. ASHRAE also suggests that while calculating I can take this value to be 75mm. I'm done with the calculation. I'm trying to justify the assumption of 75mm.
Is it between the knob and the latch that gets engaged into the wall?
Would anyone please help me out to figure it out?
Thanks in advance for the help!





RE: Door Opening Force Calculation - Staircase Pressurization
TTFN (ta ta for now)
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RE: Door Opening Force Calculation - Staircase Pressurization
RE: Door Opening Force Calculation - Staircase Pressurization
RE: Door Opening Force Calculation - Staircase Pressurization
The backset, which is the distance from the center of the knob stem to the latch to the edge of the door, is typically 2 3/8" or 2 3/4"
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm
RE: Door Opening Force Calculation - Staircase Pressurization
Equating moments about door hinge:
F1 x (W-d) = P x A x (W/2)
P = Pressure on door on lb/SF = (in wg x 62.34 lb/cu Ft water)/(12 in/ft) = 5.2 x in wg of water
F1 = (5.2 x in wg of water x A x W)/(2 x (W-d))
where A = SF door area
where W = ft door width
where d = ft distance from center of door knob to the edge of the door nearest the knob.
With door closer total force F to open door in lb
F = F1 + Fdc
where Fdc = lb force to overcome door closer
RE: Door Opening Force Calculation - Staircase Pressurization