Removing heat from second floor of barn

[gunner 6165]

48X32 pole building, reflectix insulation on walls and ceiling. The second floor gets REAL warm in the summer. I need suggestions on best way to remove excess heat upstairs. Building has soffit vents and a ridge vent.

I thought of a gable end vent fan set up on the back of the building, but I'm seeking other/better ideas. Building is used for normal auto maintenance/auto storage. No welding.

 

[MagKarl]

I had good results when I installed a gable end attic fan in my old house, I agree with your inclination.

 

[Firebrick43]

First the double bubble with a reflective barrier is NOT insulation. The advertisement the company puts out are a flat lie and false. It's a good condensation blanket and does some good in the winter reflecting radiant heat back into the building but if installed in the usual manner(against the outside metal/roof) it doesn't function to keep heat out. For any radiant barrier to work you need an air gap on 1-2" minimum to reflect the heat back into.

Second are you sure there is a ridge vent? I have yet to see a pole building personally out there. Most are a ridge cap with foam closure strips that don't allow ventilation. If the did it would allow heat out in the winter.

The best and cheapest solution in the long run is to install real insulation above a ceiling.
Anything else is going to cost you more in the long run.

 

[kbs2244]

I like the turbine type roof vents.
No power needed and they move a lot of air.

You can make "plugs" for the winter if that is a concern.

 

[raferguson]

Think basic physics:

1. Good insulation in the roof. 6 to 12 inches thick fiberglass would be good. I don't think that Reflextex? is thick enough to be good insulation. The link below says R38 to R60 for an attic in a house in Delaware. You may not need to use quite that much in a garage, but it is a starting point.

https://www.energystar.gov/index.cfm?c=home_sealing.hm_improvement_insulation_table

2. A sizable eave fan to remove the hot air. I am sure that there are rules of thumb for how large a fan (or how many cfm) for so many square foot.

I like to have the fan operate either automatically, or manually, depending on the situation. (Automatically when the heat gets up to a certain point). If you look at the building code, there should be a fusible link so in case of fire the fan shuts down. Home Depot sells them. You could use two thermostats, one higher temp, one relatively low temp, like 60F.

 

[stm317]

The best way to get heat out is to keep it from getting in to begin with. You need insulation, and radiant barrier doesn't count.

 

[jerry j]

All refrences to insulation are SPOT ON.... (The only fix that'll work.. !!

 

[Marctrees]

Be aware- the tstat one should use for an attic fan of any kind should be made for THAT purpose... having a function where it will not run the fan if temps are TOO high from Fire.

Marc

 

[gunner 6165]

Yea, I understand Reflectix isn't exactly insulation, but it's what the building has right now. My plan is to eventually fully insulate the building, I need something to get the heat out of the second floor until then.

 

[Marctrees]

Depending on the wall, floor, whatver arrangement you have .. may want to consider what I put in.

I really don't use it as for "Gable end venting", although they are mounted up there high, but for general venting of hot air, fumes, really nice during certain times of year.

Marc

https://www.garagejournal.com/forum/showthread.php?t=363857