man cave/garage AC and heat

[rfuerst911sc]

I am fortunate to have a detached three car garage in the backyard. It was originally built by the previous owner as a two bay garage . I guess he found out he needed more space so added the third bay. So there is a common interior wall that divides the two with two windows but no door way. The two bay is 24 x 26 with 10 ' ceiling at the walls and 14 ' at the peak. The single bay is 12 x 26 with a slight slanted roof basically 10 ' high. Walls in all of the structure are 2 x 4 with conventional fiberglass insulation, exterior is wood siding the interior is 4 x 8 wood sheathing. Ceiling is R19 in the single bay and R50 in the two bay. So that is the basics. Being in Georgia I don't need tremendous heat but do want to be able to heat when it gets into the 30's. Likewise the summer here is hot/humid so want to be able to cool down. Basically looking for something to set at a minimum both hot/cold then crank it up when I want to work out there.
I am committed to electric so either going to go with a conventional 2 ton heat pump/AC with 5kw heat strips OR a 2 ton dual zone mini split. If I go with conventional it is cheaper in initial cost but more intrusive due to the duct work. If I go with mini split it's more cost up front but very DIY friendly for the install. I'm thinking 9k for the single bay and 18k for the two bay.
So any of you guys using either of these setups ? Any recommendations ?

[itsnotanova]

I'm in the same situation as you. My shop is 24x30 and it easily gets 100 in the summer. A handful of times during the winter, it would be nice to have some heat. I'm still trying to figure out how I'm going to insulate it. As for the HVAC, maybe it's the redneck in me, but I'm going with the biggest window unit I can find. Just cut a hole in the building and plug it in!

[coreseller]

I have a 3 car garage and considered various HVAC options but after running the numbers I decided that occasional heat is really what I needed. The garage is well insulated in the walls and 8" worth in the ceiling, also had the upgraded insulated garage doors installed when I built the house.

I have a large workshop in the basement area so the only work I usually perform in the garage is on the cars.

For years now I've been using a simple 23k BTU Kerosene heater and it knocks down the cold to mid 60's or better within 20 / 25 minutes or so, just have to crack one of the windows 1/2" or so. The $100 price tag enticed my cheap arse side...........

[Jake Raby]

I just finished my training facility.. I have a friend that can set you up with HVAC at a great price. I just had him install a 5 ton unit to heat and cool 5,200 sq ft(2 story) for less than 10k installed.

For supplemental heat I am using a 300,000 btu ducted agricultural heater. I'll only use it when the doors have had to be open and let all the heat escape and I want a fast warm up. It'll warm the whole place up in 5 minutes.

[mountainman]

we have vacation rental cabins in the mountain of NC about an hour north of Asheville and we put in the Mitsubishi mini splits and love them. They do a great job and are very inexpensive to operate. That would be my choice for a garage as well. I was able to use single zone units and I got a great price from Acwholesalers.com in florida and I did the installation myself.

[Chuck W.]

Below is a link to the Garage Journal Forum and their Heating and A/C sub section. I have found this forum to be a wealth of knowledge and some great folks. I am betting you can find an answer there. Good luck.

Heating and A/C - The Garage Journal Board

[nieuwhzn]

Look on Amazon for a split AC. They're easy to install yourself for less than $1,000. The most important part of the install is to evacuate the unit before releasing the refrigerant, I.e. you need a good vacuum pump and vacuum gauges.
You can use the split unit for heating but as the outside temperature drops this gets rather inefficient, remember thast it is just a heat pump. I'd rather go with electric baseboard heaters.

[Nine8Six]

^ this, or...

I got the "ductless" system installed in my little shop here. About the same size as yours, a tad smaller. Works brilliantly, cheap to operate, both heating and AC, and it comes with all kind of air management & cleaning features (filtering, recirculating, dehumidifying, etc etc).

Got the Toshiba... affordable. I believe it's called Carrier in the states

[JFP in PA]

Originally Posted by rfuerst911sc

I am fortunate to have a detached three car garage in the backyard. It was originally built by the previous owner as a two bay garage . I guess he found out he needed more space so added the third bay. So there is a common interior wall that divides the two with two windows but no door way. The two bay is 24 x 26 with 10 ' ceiling at the walls and 14 ' at the peak. The single bay is 12 x 26 with a slight slanted roof basically 10 ' high. Walls in all of the structure are 2 x 4 with conventional fiberglass insulation, exterior is wood siding the interior is 4 x 8 wood sheathing. Ceiling is R19 in the single bay and R50 in the two bay. So that is the basics. Being in Georgia I don't need tremendous heat but do want to be able to heat when it gets into the 30's. Likewise the summer here is hot/humid so want to be able to cool down. Basically looking for something to set at a minimum both hot/cold then crank it up when I want to work out there.
I am committed to electric so either going to go with a conventional 2 ton heat pump/AC with 5kw heat strips OR a 2 ton dual zone mini split. If I go with conventional it is cheaper in initial cost but more intrusive due to the duct work. If I go with mini split it's more cost up front but very DIY friendly for the install. I'm thinking 9k for the single bay and 18k for the two bay.
So any of you guys using either of these setups ? Any recommendations ?

For my shop at home (three bay attached to the house), I use a 45,000 BTU Sterling class three, separated combustion with powered exhaust, unit heater with a horizontal stainless steel concentric venting system (uses outside air for combustion).



Along with being exceptionally quiet (important when attached to the house), it has a very low profile (16"), does an excellent job of keeping the space shirt sleeve warm in 0F (and even sub zero) out side air temps, while using very little fuel. You can find these units (new) for around $600 online.

[Mark_T]

Do you need to heat both sides of your garage? If I had that setup I would heat/cool the 24x26 side with a 5kW electric unit heater and a big window shaker.

Nice heater JFP. I bet that set you back a few shekels by the time it was installed and running.

[JFP in PA]

Originally Posted by Mark_T

Do you need to heat both sides of your garage? If I had that setup I would heat/cool the 24x26 side with a 5kW electric unit heater and a big window shaker.

Nice heater JFP. I bet that set you back a few shekels by the time it was installed and running.

Not really, the firm that I purchased it from ships free with no sales tax, I installed it and wired and plumbed it myself for about $350 in one afternoon, then had it inspected by the township and gas company for a $25 fee. So all in, it was less than a grand. I'm currently in my home shop, it is 65F in here and about 20F outside at the moment, and the unit has probably run less than 10 min. total in the last hour.

Well worth the expense and effort...........

[stephen wilson]

I installed the same style 2 year ago, but a Modine Hot Dawg. It's been great, with the addition of a 7-day programmable thermostat. You can ramp the heat up to be ready for you after work, or on the weekend.

[jdlmodelt]

My furnace does not out do my lack of insulation. so, I have to improve on my ceiling insulation to get it warmer in a 20x40 metal building.