Workshop Build Questions

[Kurt505WW]

I'm building a small workshop for woodworking, it's a 12' x 20' Gable roof building in Western NC
I plan to put a thru-wall AC unit as the summers here are hot and muggy. I only plan to run the unit when needed when I'm working in there which will be a couple of hours in the evening and a bit more on the weekends. I'm not too worried about heat in the winter so I'll probably run a small space heater to take the chill out of the air but nothing crazy. I insulated the floor because I wasn't sure what I was going to do when I started so figured it couldn't hurt to do that. So now I need to decide if it's worth insulating the walls, putting in a ceiling with insulation and installing a ridge and soffit vents or just leaving it open with no ceiling and not worrying about insulating since I will only run the AC a couple of hours a day. I know I can leave it open and still insulate the walls and put baffles and insulation on the rafters and still go with the ridge and soffit vents but I used 2'x4' for the roof rafters so I would need to extend them down to give me space for the baffles and insulation.
If I decide to leave it open (no ceiling) and not insulate, will I have any moisture issues at the roof in the winter? If so I guess I could still put in the ridge vent but there is no way to close that off during the summer when I AC.

Edit: I should mention that I framed it with four windows (3 large and one medium-sized) for when the temps are comfortable.

Any thoughts?

Thanks!

 

[arthur1920]

My two car garage in RI got up to 115 degrees in the summer before I put ceiling, wall and ceiling insulation. Put the ceiling in.

 

[pcmeiners]

Will you have a moisture issue in the winter ? Not only in the winter but especially in the spring and fall, guaranteed. Unless you like the patina of rust on all your tools you need insulation and heat. Since you are down south heat/AC cost would be low compared to up north, with a heat pump. An electric space heater will cost you >3x more than a heat pump. You only need to keep the temperature above 50-55 degrees, even at night.

 

[theoldwizard1]

If you have the head room, and need storage above the ceiling joists, install a drywall ceiling and AT LEAST 6" (12" would be better) of fiberglass insulation. If you want to have storage, install AT LEAST 2" (4" would be better) of foam board against the under side of the roof deck.

You want to prevent the heat from getting in in the summer and the heat getting out in the winter.. Ceiling/roof insulation is much more important than walls.

Since you are down south heat/AC cost would be low compared to up north, with a mini-split heat pump. An electric space heater will cost you >3x more than a heat pump. You only need to keep the temperature above 50-55 degrees, even at night.

Concur ! Electric space heater get expensive quick !

For a few $100 more, you will be comfortable in summer and winter. You could probably recover the additional cost in a couple of years and then be money ahead for the rest of your life !

 

[Kurt505WW]

Thanks guys.
I'll insulate and put in a ceiling.
I hate to lose the storage space but it will be worth it.

 

[Ak Jim]

Maybe just have a spray foam company come in and spray the ceiling, that way you wouldn’t lose the storage space. It’s a fairly small building so the cost might not be too bad.

 

[Jackfre]

I think you will find that the windows are going to limit your useful space in the shop. Yes, it is nice having a nice view, but it is also nice being able to place the gear you have and will get where you want it rather than where it can go. In my last shop I put the windows at 54” so I could use the wall space below and still I had too many windows. Nice view though.

 

[ghnl]

I agree that insulation will be worth doing. It will minimize heat gain in the summer & heat loss in the winter.

Do look into a mini split heat pump. They work very well for A/C and also can provide heat. They do lose heating efficiency when it is very cold (below ~ 20*F to 30*F) but if you are like us in central NC those days are rare.

 

[captaindiode]

You need to think about humidity control, even when you are not working out there. I am in the foothills of NC and the moisture will rust your tools and lead to mildew on stored wood. I would insulate and think about a mini-split. Many have a dehumidifier mode. That or use a stand-alone dehumidifier to control moisture.

 

[Kurt505WW]

Thanks for everyone's thoughts. I've decided to go for it and insulate, put a ceiling, ridge vent, soffit vents and ac/heat.
The mention of windows taking up too much wall space is a valid one but because the shop is on our property and visible as you enter my wife wanted it to look as nice as possible and windows help with that. Also, the weather is so nice here in fall and spring it will be nice to have fresh air coming in.