Hot Rods How to keep the shop cool? V

Now I have a6 car garage I am trying to find ways to keep it cool enough to work in. The last owner did heat and air and I think he used it for mainly storage. There’s a 3 ton A C unit and I also in stalled. 5,000 B T U A C unit and a big fanThursday it was cloudy and with everything going I got it down to 70 degrees that was nice but when the sun is out I can only work till 1 or 2 p m before it gets about 90degrees in there a friend said in stall 2 turbine fans on the roof and that would help. I am not crazy about climbing on that high roof so I wonder if I installed 2 exhaust fans with shutters 1on each end of the shop if that would help ? Thanks in advance Bruce.






Thanks in advance . Bruce.

 

120 in the desert in the summer. I have a big side draft swamp cooler I point right where I'm working.

 

Two years ago I put a dual zone mini split in my 50x60 -10ft ceiling garage. Before the install I insulated the hell out of the roof and walls.
I’m in Ohio and it’s not uncommon to have 90+ degrees days with really high humidity. That said, I usually just need to put the system on the dehumidify setting ( not full AC) and the temps stay around 70 inside and any bare steel doesn’t rust. I love it!

 

Insulation...it works wonders! As thick as you can afford. Add reflective silver mylar insulation sheets.
https://www.amazon.com/s?k=reflecti..._9624363&tag=hydsma-20&ref=pd_sl_3cyt0dnbkl_e

Plus a SMALL exhaust fan up high. A large exhaust fan defeats the purpose because it ends up sucking in too much outside air around your doors or any other holes around your shop.

 

Im with the insulation crew too.. Spray foam works great if its in your budget.

 

Insulation is the key. As for exhaust fans, if you're talking about ventilating an attic that's separate from the working space that's one thing, but if you're talking about connecting them to the working space they would just fight against the air conditioning.

 

I live in Ky and you in Tn, so I imagine we are looking at the same problem. I have a 40x60 building that has 6" insulation in the walls. I installed a metal ceiling which I like very much. Having a flat ceiling cuts down on heat rising into the truss area in the winter. I put spray foam on the upper side of the metal ceiling to make a membrane and seal the seams........then blew fiberglass on top of that. My building holds heat pretty well in the winter using an overhead furnace. I can leave the heat off for weeks and the building never gets below about 50/55 in the winter. Now thats compounded by the fact that I have lots of stuff within the building and lots of raw metal.........so that makes it somewhat harder to raise the temp, but the hot air gets it up to 70 and shuts off and on like a house does. The 40x60 has a 12 1/2' ceiling. I also have a 12 x60 leanto with an 8' ceiling that is open to the pole barn. So about 2900 sq ft.

Moving to the cooling. I have yet to work this summer (with its many 90 plus days) with my overhead doors open. The metal and other treasures helps keep some cool inside the building. Its noticeable when you enter. Rather than try to air condition the building, I chose to place fans of various sizes in places where I work. I got a couple of used industrial wall fans and mounted them so they could pivot.
I have a lift, so one of them is positioned to blow right where the front of a vehicle would normally be. Another is for general use in another bay and can provide air pretty much anywhere I'm working. Over at my bandsaw and my welding table I have small 8" fans that can be flipped on when working there. I often leave something I welded on the vise and turn the fan on for quick cooling.

Over where the lift is, when I'm directly under a vehicle, I had a squirrel cage blower and set it on a bench at the back of the shop. Changed the pulley to slow it down and it makes a nice gentle breeze under any vehicle I'm working on.

I gave my son a medium sized squirrel cage on a roll around cart. He loves it. Somehow it puts out a large volume that goes all the way across his shop without blowing really hard. The key is often to slow them down.....and people practicaly give them away......$30-$50. Anyway, I have found that putting fans where you need them works really well as long as you slow them down.

The problem with A/C is you can't open your overhead doors without loosing all the kool........and its expensive. But if you can afford it, its nice. I always found that if I was working hard, I would sweat even in an a/c building.....so I'm happy with slow moving fans.

 

Ok guy thank for all the input The last owner put in very thin insulation it’s almost like bubble wrap I think I might go with the white board insulation like I did in my old shop( I built a box around my new compressor which I moved inside) and did the walls around it with the white board insulation which really quited it down I am just Not sure I can reach the ceiling todo it Thanks in advance and it’s good to be back on the HA M B! P S here’s what the last guy used for insulation.

 

Consider sectioning off a work area and insulate the hell out of it, then use a mini split or other form of A/C to
cool it. Cooling off 2400 square feet to work on one vehicle is foolish, a 2 bay work area is usable and reasonable to
heat/cool.

 

what @jetnow1 said , 2400 sqft is a big area to cool off .

couple suggestions


1. Insulate the crap outta everything , ceiling is the most important .

2. section off a work bay 1000-1500 sqft is much easier to cool , lower ceilings with insulation .

3. the shop at work is 15,000 sqft we have 2 big doors at the back of the shop and a large door at one end on the front and a man door on the opposite end .

we have 8 ceiling fans and 4 pedestal fans we can move around . The shop is “ok” during the afternoon as there is always a bit of a cross breeze coming through .


A/C is awesome but in this day and age the cost of electricity is something to consider as well .

 

Do you need to cool the entire shop or just a workspace? I would a curtain off a generous workspace and cool that on top of proper insulation.

 

In my shop I cut it into a couple different rooms and I insulated the one I work in (42x48), but just have a minimal vapor barrier on the storage side. It's amazing the difference. it's not un-common to have a 30 degree difference between the two rooms with no heat or air on and the only change being the insulation. I did R22 fiberglass bats (6") in the walls and ceiling , but the ceiling is over a R7 vapor barrier for a total of about a R29 insulation value. It really shows hew well it works walking from one room to the other of the same building under the exact same conditions.

I think any money spent on AC is a waste until you have real insulation, and any money spent on insulation is about the best money you can spend on a shop (or house for that matter!)

 

Google Big Ass Fan.

 

My home shop is 42x60, with a two story apartment on the south end, which, since the previous owner who had it built was an insulation contractor, is heavily insulated. Small and old gas heating system feeding only the apartment, no AC. We are lucky here that it cools off a lot and quickly in the evening, cool air coming up from the Bay. Have the house torn up right now, so staying in the apartment. I keep it closed up as much as possible in the afternoon, and open things up in the evening and the morning, and a little help from a couple simple box fans on low that use very little juice. Just closed the 10' wide back door of the shop at noon (west side) and it is now 81 outside, 72 in the apartment, and 64 in the shop ( was 60 at 9AM). If I don't generate any stink in the shop, I can leave open the 36" door to the apartment and it will transfer and cool the apartment during the day, with no fans running. On warmer days in the winter, open up in the afternoon when it's warmest, mother nature can be kind if you let her

 

From the pics posted it seems like a metal roof garage/shop with out and attic.
You could spend time and money for supplies and make an attic structure, even not insulated it’ll be a barrier. Then put a blower fan on one end with the prevailing wind, a suction fan on the other end. That knocks the temp out of the attic area to ambient temp.
When my folks had their roof redone shake/wood was not legal anymore, so a composition shingles were used. After that if you put your hand on the ceiling inside during the summer, it was very warm. The house is/was poorly insulated (built in the teens as I recall) but adding the fans made a heck of a difference.

 

Shade trees

 

I don’t think there was anything mentioned about garage doors or vehicle doors. I use a two car garage for my shop with an 16’ X 8’ door. I insulated it with foam panels with a plastic panel on one side. The door has a southern exposure and prior to insulating you could not lay your hand on the door it was so hot from say 11am to 4pm. Of course that heat transferred into the shop. So might want to look at your door/doors. Also blew in about 24” insulation in ceiling. Those two changes made a huge difference. Also run a dehumidifier 24/7 year round feels cooler with added befit of keeping tools, metal from rusting in Southern Alabama humidity.

 

That sounds like a good idea. Thanks

 

I do miss them here!

 

He beat me to it. The same concept as closing off part of your house that you don't use much to only cool the rooms you spend your time in. just hanging some visqueen or tarps to cut down the area you are trying to cool to the area you are working in should help.

 

Heavy Visqueen to make a smaller work area & allow light to pass through. And this:

 

Folding diver wall{ homemade or not}/one at what ever end you can also mount a AC at.

 

Thanks guys good to be back!Bruce.

 

I have a 4 foot tall swamp cooler on wheels. Just direct the air flow to the work area. It won’t cool the garage down very much ( about 20 to 25 degrees), but it is better than the 100 plus degree days .

 

Bruce just to give you some idea, my garage is 24 by 30, 9 foot ceiling. I have about r21 walls, r 40 ceiling. One mini split 12k btu keeps it cool no matter how hot, and heats it to about 62 even in 0 degree weather. Cost to run in summer is probably about $1 a day, $2 in the heating season. It also keeps the humidity so low I have zero rusty
tool issues. A large storage area would be nice, I have a walk up attic but obviously can only carry up items I can carry,
but I do not heat or cool the attic. there is often a 50 degree difference between my work area and the attic.

 

Insulate as much as you can afford, it will have a big payback in your electric bills. Weather strip all the doors and windows like you live in the North Pole. Only this time it's to keep the heat out, not in. When you move cars in or out, do it in the early morning or late at night when it is cooler. All of this will make a big difference in the winter when you try to heat the place also.

 

You look to have a nice big shop that is one to envy. The trick is to figure out how to make it comfortable. It maybe an idea to see if there is an organization or home owner off the grid type groups that may be able to recommend ways to improve insulation efficiency. Someone that could evaluate what you have and make some insulation & general building recommendations at a minimal cost. There is a balance between the cost of the insulation and the return on the investment. It is to find what that balance is with respect to heat and cooling for your area. The pay off is that good insulation works both ways to reduce the utilities cost and improve the efficiencies for cooling and heating.

The reflective bubble wrap cannot be all that great or Canadians would be using it as an economical method of boosting insulation. The temperatures locally range from -40F to +100F. The more real insulation the better. If you have a closed attic then it should be well ventilated to shed the heat out of there. Our old house had a 1-1/2 ton AC for a 1200sq.ft. residence with R20 wall insulation and about R 40 in the attic. In the high 90's the AC was borderline. This new old 1958 house was switched to high efficiency forced air heating and cooling the contractor recommended a 1-1/2 ton unit. I had him install a 2 ton unit as it was not much more. The 2 ton AC has no issues cooling the house. The windows were all late 1950's and at -35F it was noticeable. Plastic was put over the windows the last 2 winters to cut the cold and drafts to try to make it better. The windows were all upgraded last Friday to R6 insulation value. The 96% Hi Efficiency furnace reduced the gas bills significantly over the previous winters. It will be interesting to see what the windows do for reducing gas usage. When I bought my first house in 1981 it had 8 inches of attic insulation. 2 years later 6" of fiberglass batting was added at 90 degrees to the first layer. The drop in the gas bill paid for the insulation in the first winter.

The 3 ton in your shop would be too small given the area and volume of the shop with the type of insulation. A lot of good thoughts here starting with isolating a section and concentrating cooling there. Add all the insulation that you can afford even if it is incremental and takes some time. It will pay off in the long run. If the insulation can keep the shop cool with 3 tons then it will take next to nothing to heat it. Here a lot of guys living in the country have large shops with a wood stove and a couple ceiling fans for heat. My friends shop has a ceiling fan directly above his Valley Comfort wood stove where the shop could be around 10F in the morning when it is -35F outside. The fan directly over the wood stove helps warm the shop up to 70F in an hour. A well insulated shop is comfortable when it is hot outside without AC.

This house came with a 900 sq.ft garage that I am working to upgrade on the outside and then the inside. It has R12 insulation in the walls. Menards had a great sale 2 years ago on 2" dense foundation grade R10 foam board so I brought home a 5 ft stack for garage. The plan is to upgrade the wall insulation to R22 and eventually the attic to R60. The 1970 tin garage doors are going to be swapped out for R16 or R18 units as the tin doors conduct heat and cold without any mercy. The intent is to make the garage semi reasonable to heat for most of the winter and that will make it fairly comfortable for summer.

 

Build you shop in Anchorage.

 

Our shop is 40x50, four inches of fiberglass in the walls and six inches in the ceiling. (I probably should have put in more) So far this summer we have only used the A/C a couple of times.........when it gets to 80 or so inside the A/C comes on. We like to have the doors open but we don't like to sweat too much. As stated before....insulation is the key to keeping the temps reasonable.

 

My shop is cool. 1st stall has my chopped '36/'37 Chevy Pickup project. 2nd stall has my '47 Buick Sedanette w/ 500 Cad motor project. If it wasn't cool, those would be an '07 Mustang & an '85 'vette. Stay cool!