Mister for cooling metal work building?

[texasjohn]

I'm building a 40X60 metal building for all the usual reasons. It will have a passive ridge vent running the entire length of the roof peak and efoil bubble insulation/radiant barrier on all walls and roof. Concrete floor, 16X14 rollup door on one end, 14X14 rollup door on the other end, 4X7 walk doors on both sides, one 3X7 walk door on an end.

I'm thinking about installing a bunch of mist nozzles as additional cooling. Anybody tried this? I've looked on the net and seen numerous kits. Everything I know about this is summarized at http://www.mrdrip.com/mistingsystems.htm . My understanding is sketchy, but boils down to:

place misters 10' off the ground
place nozzles every 2 to 2.5 feet... that's 600 nozzles for 40X60 bldg??
one mister uses .5 gallon/hr, thus 600 would use 300 gal/hr = 5 gal/min??
use a lime reduction filter because I have hard water
And, a sediment reduction filter
150 lbs water pressure or therebouts is needed
use an automatic drain valve
conservatively, on a 100 degree day I could expect the bldg to be 80 degrees.

Seems to me that I'm confused re the number of nozzles and gallons per minute that will be required for a 40X60 foot building.

Anybody have experience with misters and/or using them in a work shed/shop/garage metal building?

 

[MrJimi]

We live in Florida and we use insulation, no maintenance and always there. And no water bills etc. and break-downs.
Really, give insulation a thought, no moving parts.
One more thing
water + metal building = rust and like Mike says, humidity
Jim

 

[PineRidge]

I have no experience with misters but I would be concerned with the humidity problems within the building if you use them.

 

[Egon]

The Mister's will require much additional maintenance on the water treatment facilities. Electrical costs for the water pump will also escalate.

Think passive - like insulation

Egon

 

[WhyNot]

The farm where I work uses mister's in the freestall barn's to kep the cow's cool while they work great from what I see is that with in an hour of them running you would be working in a small lake they put out a lot more water than one would think.

 

[RedRocker]

It's kind of humid here for swamp coolers, but it might help a little.

 

[BB_TX]

The misters work on the endothermic principle that water evaporating absorbs heat from the surrounding air, making the air cooler. That is why evaporative (swamp) coolers work so well in desert regions. However, in high humidity, all you get is wetter air. And I think that is what you will get most of in central TX. And if the air it too humid, you will probably get wet floors (and whatever else is in the building).

 

[texasjohn]

All good points.

Humidity averages for May thru Sept, when it averages over 75 degrees, are: 59%, 54%, 47%, 49%, 57%.

I'm led by manufacturers to understand that a temp reduction of 20 degrees is possible with humidities between 40% and 80%.

I was thinking that I could turn the mist system on only when working in the building... thus hopefully avoiding a total mist-down of the place.
Am still looking into it... insulation is good at keeping cool air in... or hot air out... but neither cools nor heats air. I do have some insulation installed already.

Am hoping that somebody who has tried a mist system on a large scale will comment on their experience.

 

[dooleysm]

When I was in college a few guys in our non-air conditioned frat house tried swamp coolers in their rooms. They did not work in the humid Indiana summer. They just added more humidity to the already steamy rooms. I would think that some big fans would work better.

 

[Bird]

The swamp coolers were the only kind of cooling we ever had in our homes until I left home when I was 19 years old. And that was in south central Oklahoma and north central Texas. And they really do help, but only if you're standing, sitting, or lying directly in front of the air flow. I started working nights when I was 19 and I bought a little portable evaporative cooler; held one gallon of water. I set it on a stool right beside my bed so it was blowing right in my face. That was about the only way I could sleep in the Texas summer daytime heat.