Most efficent humidity control during warm season for shop?

[Michael Yadfar]

For the late fall, winter, and early spring, I learned that keeping my shop heated at a constant temperature was the best way to control potential rust issues, and other issues associated with humidity. In the late spring and summer, I'm still scratching my head over what to do. I have a really small shop, 8x16, and it's pretty well sealed and insulated, although light (R-13 in walls, R-10 in floor, and r-20 in ceiling). My woodshop is more of a winter hobby, although I will still use it in the summer, just not as frequently.

From what little I understand, I have three options:
1. Keep windows open and blow fans
2. Run an air conditioner
3. Run a dehumidifier

Btw, either way I already keep my cast iron surfaces waxed. What I'm trying to find is a system that both works, and is efficent energy wise. I live in Southeast PA, so we don't have swamp conditions, but it does get humid. People say air conditioning and dehumidifiers do the same function, but I would imagine a dehumidiifer is still more energy efficent,

[John Donofrio]

Hi Michael,
I use a whole room dehumidifier even though also run a mini split a/c unit. If you have any windows in your space, a window a/c unit should do just fine. Another option would be a small stand alone a/c unit. With these the condensate drains into bucket or could be piped to a drain but you would still need a window for the exhaust (hot) air. Either way be sure to clean the filters often due to the dust generated in the shop.

All that said, I would vote for the dehumidifier if your not interested in cooling the space.

[Bruce Wrenn]

A dehumidfier will add heat into your shop. My vote goes for window unit. As you don't really need temp control, get a humidistat and plug AC into it. When humidity goes up, AC comes on. Cuts off when humidity drops.

[Dan Case LR]

I live in the Sticky South where battling humidity is a way of life, and I support several sites where controlling humidity is critical. There's no substitute for a good air conditioner IF IT IS SIZED CORRECTLY. The most common mistake people make is using an AC unit that's too big. It cools the space so quickly that it doesn't have time to remove humidity. I had one site with a 40,000 watt radio transmitter that had been well-designed except for the over-sized AC units. It's important to keep these units cool, and the unit did that--but the air inside of the building was so damp you could almost shower in it. When that unit finally died, I put one in that was properly sized and the difference was amazing.

If you're more concerned about humidity than temperature control, get a window AC unit that's a little too small for the space. It will run a lot, but it will keep the humidity well under control. In my shop, I have a window unit with a digital temperature readout. When I'm in the shop on a Summer day, I'll turn it down to whatever I find comfortable, but when I leave the shop for the day I set the temperature to 85 degrees and leave the unit running. By doing that, it runs often enough to keep the humidity reasonably steady and under control as long as I don't do a lot of work with the garage door open.

D.

[Michael Yadfar]

I live in the Sticky South where battling humidity is a way of life, and I support several sites where controlling humidity is critical. There's no substitute for a good air conditioner IF IT IS SIZED CORRECTLY. The most common mistake people make is using an AC unit that's too big. It cools the space so quickly that it doesn't have time to remove humidity. I had one site with a 40,000 watt radio transmitter that had been well-designed except for the over-sized AC units. It's important to keep these units cool, and the unit did that--but the air inside of the building was so damp you could almost shower in it. When that unit finally died, I put one in that was properly sized and the difference was amazing.

If you're more concerned about humidity than temperature control, get a window AC unit that's a little too small for the space. It will run a lot, but it will keep the humidity well under control. In my shop, I have a window unit with a digital temperature readout. When I'm in the shop on a Summer day, I'll turn it down to whatever I find comfortable, but when I leave the shop for the day I set the temperature to 85 degrees and leave the unit running. By doing that, it runs often enough to keep the humidity reasonably steady and under control as long as I don't do a lot of work with the garage door open.

D.

The problem with me is my shop is so darn small. The smallest AC unit I see on Home Depots website is for a 150 sq ft room, my shop space is 128 sq ft

[Bruce Wrenn]

Remember that room is in a house, which means no more than two of the walls face to the outside. You are basically going to have to get a 5000 BTU window unit, as this is as small as they make

[Michael Yadfar]

I looked up the cost to run the air conditioner, and to my surprise it's actually cheaper than heating the shop, and that's running continuously!. That was one of my worries. Heating was about $40 a month, and running a 5000btu AC unit continuously is $36.

[Tony Leonard]

I live in Memphis. My shop is 16x20x10 and well insulated. I have to have heat and AC, so I use a unit that is a little oversized to get one with heat. I keep the temp reasonable to save energy. I have to run a dehumidifer in the summer. I have no idea what the whole setup costs, but I haven't tried the option of keeping the shop cooler. The original unit was WAY too big and that's when I started runnning the dehumidifier (17 years ago). Our total electricity usage doesn't seem out of line with others. Same problem in the house - the unit is really too big and doesn't run long - feels calmmy a lot. Will address when it dies. Keep in mind that if you run a dehumidifier, you need to empty it or run the drain outside, etc. My tank is probably 1 1/2 gal and I have to empty it once or twice a week in the summer. That seems like a lot of water! I recently built my own controller ifor it (the original and the replacement died) and I keep it at 50% (ish - humidity sensors are not that great).
Also, I take the unit apart and clean it real well (well, both units - ac and dehumidifier) yearly. I cover the dehumidifer if I am making lots of sawdust. I built a frame around the wall unit and keep a pleated filter in front of it sealed with foam.

Tony

[Michael Yadfar]

This is a really tough call, because I feel both are necessary for proper control. If I had to choose between one or the other, which should I choose? My biggest issue with an AC unit is days like today, when its 70 degrees with 90% humidity. The air conditioner probably wouldn't run. I feel like it would be good to have both, using the AC only when I'm in the shop, and using the dehumidifer when I'm not. The only issue here is cost right now, so if I absolutely need both, I'll probably buy them separately. I'm almost feeling like a dehumidifer should come first, but that's just based on my understanding

[Lee Schierer]

It might help if you provide an idea of what your shop construction is. Is it a basement, out building, attached room of the house, etc...

[Michael Yadfar]

It might help if you provide an idea of what your shop construction is. Is it a basement, out building, attached room of the house, etc...

The building is an outbuilding, a converted wooden shed. The building is 9x16, off the ground, and has a high gable roof. I have it insulated with r10 in the floor, r13 In the walls and doors, and r20 in the ceiling. I also have new windows, and everything is sealed with either caulk or tape