Second story rollup doors — why?

January 30, 2014 8:51 PM

Industrial buildings frequently have rollup doors on the second or even third story. The ones in question don’t have a horizontal I-beam or timber to hang a winch or block & tackle from, (like you’d see on a hayloft,) so they’re not for day-to-day loading/unloading. The ones I see in the city are generally facing a sidewalk, not a dedicated open space like a loading bay or parking lot. What are these doors for? The only guess I’ve come up with is occasional installation of equipment that’s too big for a freight elevator. But large-scale machinery usually comes in pieces and is assembled on-site, and the stuff that can’t be (e.g. large pressure vessels, crucibles, this thing) isn’t stuff that’s ever installed upstairs in a general-purpose light industrial building. I’m stumped.
posted by El Mariachi to Grab Bag (6 answers total)

Could be for easy ventilation? Loading things on/off a flat bed truck?
posted by dfriedman at 9:19 PM on January 30, 2014

I am only guessing, but perhaps for ventilation? Here is a link to non traditional residential uses for garage doors. Also here is a townhouse in NYC that has one in its second floor. Not sure it answers the question, but both links are very interesting.
posted by JohnnyGunn at 9:22 PM on January 30, 2014

Best answer: I've used dozens of these doors to get electrical equipment in and out of MCC or electrical rooms. Electrical equipment while not all that heavy (though transformers can mass a lot) is often too tall to fit through the interior doors leading to the equipment rooms and would otherwise require extensive dismantling and reassembly. It's always better to get these things as assembled as possible from the supplier. A hole in the wall with a roll up door is cheap compared to specialized labour to dismantle and reassemble a cabinet. Heck some buildings don't even have the roll up door; just a section of wall designed to be unbolted and lifted out of the way.

Another thing we might us this sort of door for is cable. A big spool of cable can easily weight several thousand pounds and that might exceed the limits of the freight elevator. A 500m spool of 3c500 teck for example tips the scale at a smidge under 3500kgs.

But they can also be used for supply. A light industrial facility with a cabinet shop on the second floor might receive lifts of plywood via a second story entrance because it is faster/easier to use a telehandler to lift the wood to the second story than it is to bring it through the building. Or the building might not have a freight elevator or at least not one that can handle 8' long material. A lot of freight elevators are designed to (barely) hold two standard pallets.
posted by Mitheral at 9:24 PM on January 30, 2014 [3 favorites]

They could be used for loading and unloading with a boom fork lift.
posted by halogen at 9:42 PM on January 30, 2014

I'd say that it's for some kind of loading and unloading, too; look at the scrapes and gouges at the center-bottom of the opening. (And heck, when something like this makes me curious enough, sooner or later I give in and go ask the source!)
posted by stormyteal at 10:00 PM on January 30, 2014

In my experience, both printing presses or phone switch equipment can be enormous and also installed above the ground floor.
posted by wenestvedt at 3:24 AM on January 31, 2014