How big of fan?

[deepsea]

24 x 41 x 8 pole barn with a roof peak at 12 feet located in southern Louisiana. How big of an exhaust fan should I get and what kind of thermostat should go with the fan? I may just cheap out being insulating for an AC can get so expensive. Ill still insulate the roof but that may be it. Suggestions?

 

[Deltarat]

I got one from Lowes, I am not sure of the size,but it tells you the square footage it exhausts on the box. The thermostat and humidity control comes with it. About $100.

 

[deepsea]

I saw the same set ups at HD rated at 1000cfm or higher. That will exchange the air every ten minutes. Plenty of ventilation but can that actually create a breeze? Im sure other cheapskates have considered this option. Is there a calculation to see if this will equal a 5 mph breeze or so? Such air exchange could make heavy insulation obselete. I wouldnt have the fan set up so aggressive when the shop was unoccupied

 

[green.bubbly]

I would approach this a little differently. Use a typical 1000 to 1500cfm attic fan to exhaust the heat and use a secondary fan on the floor to create the "breeze".

Growing up in south Louisiana, I remember having a whole house attic fan that would draw air through the windows and it created a nice breeze but it a was pretty big fan. Something like this...

 

[Grumpy365]

Look at it like this. Your building is 7,872 cubic feet (21x41x8). So a 1500 cfm fan moves 1500 cubic feet of air every minute. Now extrapolate what kind of air turnover you would like to see.

 

[deepsea]

Not bad bubbly I like your style. I was afraid I was gonna get a bunch of naysayers. If condesation stays at a minimum I don't see a downside. Stop me before I do something dumb though. Open a shaded window and put the fan up high (where the hottest air is) I suppose

 

[Falcon67]

The $100 fans at Lowes/HD move 1600 CFM. They will exhaust heat but will not create a breeze for you. I know - I'm using one for exhaust. Be sure you have sufficient outlets for the air. A whole house fan would be the best, but you'll need holes in the roof/gables/etc to let out at least 4700 CFM.