I am just starting to build a shop in my garage/basement in Bloomington, IN.
The biggest concern I have is excessive humidity. Does anyone have any
advice on choosing the right dehumidifier for a 900sq foot basement with 7 ft. ceilings?
It is VERY damp here in Indiana during the summer, and I would much rather buy the
right dehumidifier now than deal with rust and wood movement.
thanks!
vincent
Replies
If it's very humid, and hot, why not install an ac unit? I don't know as much about dehumidifiers, but for ac units (window), 10,000 BTU minimum works for 900 sq ft.
The bigger the better, for this.
The problem with an AC unit is that the basement is naturally going to hover around 60 degrees even in the summer due to the concrete floor being below grade. An AC unit really needs to run for quite awhile to dehumidify, so you would have to turn the A/C down all of the way. You don't want to have to work in a meatlocker atmosphere. The A/C is not the answer. A straight dehumidifier would do the job, and at a lower operating cost.
Part of your response makes sense, but I have never been in a below grade basement which "naturally hovers" at 60*. It's always more like 75-80 in an unconditioned space. I suppose the humidifier is the better solution.
Or plenty of oil to coat his tools with.
Concrete is usually about 55 degrees and basements are, as you say, unconditioned space. Only the amount of basement wall that is above the grade level will temper the basement air. The humidity can vary widely, of course. My point is that a A/C unit will never run enough to dehumidify a damp basement. The same is true of trying to use the home's central A/C system to dry a basement.
I have a basement shop and I bought the Sears 50 pint dehumidifier. It's nice because it's not just on/off or high/low; it has the ability to set it at a particular humidity level. I've set it to 55% humidity which thankfully results in it not running all the time and ringing up an incredible electricity bill.
So far no rust problems on the tools. Probably thanks to heavy helpings of WD-40 and wax on the tablesaw top.
Thanks for the advice- I was hoping to hear some good feedback on a sears unit because I feel that sears usually provides better customer support than most other appliance dealers in my area. It would be nice to be able to control humidity to a percent value, because I will also be storing some stacked lumber and I would like to know that it is at a rather constant
moisture content. You mentioned using lots of WD-40. You may want to try a product which I found through 'http://www.japanwoodworker.com' called Camellia Oil. It comes from the camellia flower, and although it is a bit expensive, it provides great rust protection without the smell
of WD-40. Also, unlike vegetable oil it will never cure into a sticky film, even after many years.
It was the choice of japanese samurai who used it on their sword blades in order to
prevent rust in japan's overly humid climate, and has been used by woodworkers there
for centuries, mostly to protect valuable hand tools, but I don't see why it wouldn't be
good to use on power tools as well.
Camellia oil does work well but tends to rub off quickly, Boeshield T9 is also expensive but lasts much longer, about six months on my daily users. I use the oil on my hand tools and the Boeshield on the cast iron.
Since the house is on fire let us warm ourselves. ~Italian Proverb
I am on my second dehumidifier for the basement, in 22 years. It's probably a Sears model, this one is about 10 years old, and is adjustable. Just have to remember to look to empty it. My first one had a tank which could be connected to a hose to drain directly to my sump pump, but my current one does not. Just make sure you have enough air circulation to evenly dehumidify the entire basement. A floor fan will work just fine.
"My first one had a tank which could be connected to a hose to drain directly to my sump pump, but my current one does not."
Try removing the tank and looking up into the machine. I've run into machines where a hose could be directly attached, but the tank had to be removed.Dan Kornfeld, Owner/President - Odyssey Wood Design, Inc.
I recommend you first get a Thermo-hygrometer from Oregon Scientific (or Radio Shack). This will let you precisely monitor humidity (and temperature) from the room you're in, and from 1 or more remote locations (such as upstairs) with a wireless remote sensor. Then you can try a series of measures until the humidity is consistently in the target range (maybe 45-50% or so).
For instance, the first cheap thing you might want to try is to divert all downspout run-off to at least 10' away from the foundation walls using plastic drain pipes ("elephant trunk"). Then you can try sealing around the sill plate and any penetrations. Consider painting the basement walls with Dry-Lok, then insulating the walls and ceilings. If the basement is still too humid, get a dehumidifier (not an air conditioner) and drain the condensate out with a condensate pump (through a dedicated pipe, or existing condensate line, but NOT through a waste line). The Santa Fe humidifiers seem to be the best on the market. They are pricey, but so is the damage from rust and mold.
I think you ment this post for Vincent.Dan Kornfeld, Owner/President - Odyssey Wood Design, Inc.
Is the 'dry loc' product you spoke of a vapor barrier? If so this seems like a very good idea since I have done a lot of house painting, and painting on a barrier is more appealing than using one that needs to be tacked up/ mounted. I am also considering adding insulation just to the top 4' of wall (only about 2' are above grade). Do you think that the moisture barrier w/o insulation would be sufficient on the lower 4' of wall space? I also really need to have my basement drain cleaned. I want to try to rent a drain pump rather than paying a plumber; does anyone have any experience with this?thanks for all the feedback-Vincent
Insulate the walls first, then cover them with drywall, slatwall (better for hanging things) or whatever you want. I used 2" foam in my basement because it got too cold in winter and raised the temperature quite a bit. With the dehumidifier in summer, it's actually pretty comfortable. Not quite as cool as before but not as muggy, either.
Thanks for the tip-Do you think I should cover the entire wall, or just the top half where it is above grade?
I was also planning on stuffing some fiberglass insulation up into the rafters along the perimiter of the room because I've heard that a lot of heat can escape through this area as well. This work will most likely help lower my overall heating and cooling bills as well.
My house is a 2 bedroom 1920's bungalow, with A/C upstairs. The floor is not insulated between the basement and the upstairs, so I imagine some of the cool air will find its way down into my shop and help to keep things comfortable. The furnace is down there too, so there is never any proble with heating in the winter.
vincentedwards,
It seems to me you've got a number of issues to deal with to get that space comfortable and useable. It might be best to back up a bit and look at the situation in total before you put your money down on any one solution. I live 5-6 miles from the ocean, my basement shop never gets any rust..go figure...recently, I used the dehumidifier because of 29" of rain this spring and seepage through the concrete walls...humidifier kept icing up..other than that it worked. If I had enough money I'd like to consider one of those air conditioners that don't require a window and can be rolled around...this would allow me to control the environment and with dust control keep the furnace safe(kinda)
Issues that pop out are the concrete floor and the 7' ceilings..and sufficient lighting for your work space. Also, if cool air can get down, maybe dust can get upstairs? I can assure you, heated or not, that concrete gets real hard and cold in the winter and you feel that up through your knees. I used a Dricote panels for a portion of my workspace which works great.
Many have suggested drywall or something light colored on the walls to help with lighting issues.
Lastly, I'm learning that a good moisture meter can and should be used throughtout the furniture building process not just when wood is purchased.
To sum up, perhaps you should figure out all the details first for your space and then determine if the air needs to be conditioned ...and what is the best way...
yes-
This is a less than ideal space in many ways, esp. the ceilngs. I am planning for the most part to make small to medium sized furniture, so I think I will be able to live with it for now. It's really exciting just to finally have a space that is my own rather than using a community shop where machines are never set up quite right and parking is a challenge. As per dust- I've done some pretty heavy sanding down there with the garage doors open, and I didn't notice any dust coming upstairs. And that was without a dust collector.At the moment, I have all my hand tools in a spare bedroom upstairs, with my workbench, until I am able to make the basement space more inviting. The power tools have not been purchased yet, so now is the time to make the space as workable as possible. I do have five 4' 2bulb flourescent fixtures in place in the area I plan to use first. 2 of them have daylight spectrum bulbs. There are also many standard fixtures in the ceiling with bright flourescent bulbs in them. Along with these are outlets in the ceiling and a few on the walls where I will add power strips. Finally, there is a 220V outlet where I want my nice bandsaw (tool purchase #1) to go. All this said, I believe that getting a decent 1-micron filtered mobile dust collecter and a sufficient dehumidifier would be a good place to begin, since these two items will drastically improve the quality of space. The insulation will come next, since I had planned to do that for energy reasons anyway. As I get more money, proper wiring and more power tools will follow. If anyone else has any feelings about essential items in a bare bones startup shop, i would be happy for the advice.
VE
I just replaced my old Sears with a new one. I got the biggest one they sell, vor my basement which is about 1400 SF. I would chekc Consumer Reports if they have recommendation. The noise is the biggest drawback. When it comes on, you can hear the fan running, especially at night.
You've got a lot of great feedback. Just from my experience, I have an air concitioner in the basement and it works fine. It is an old type and conditions the outside air coming in, so you have some air exchange. I decided to do the same in my garage shop with opposite results. First I got an air conditioner that was too large and cooled too fast. By cooling too fast the compressor would shut off and not remove the humidity. Then because the floor was the coolest, I would get condensation on the floor. That said, I would use the dehumidifier. I have both. Good luck and happy woodworking.
The condensation is from the part below grade, the warmth is from the part above. I would do the whole wall, then add a vapor barrier before covering it, just like any other wall in a cold climate where condensation could be a problem. The floor will still be about 55 degrees but with a good dehumidifier, it'll be a lot more manageable than it is now.
"I cut this piece four times and it's still too short."
You mention that you have AC upstairs. I have a humid basement that's below grade and for the record is too hot when the weather in the Philly area is in the 90's. I have a dehumidifier and its not quite enough to keep it right. You should run the dehumidifier output to a sump pump if you have it so you don't have to empty the bucket every day. I often plan when I'm going to work in the basement shop which is usually at night so I leave the basement door open when I go to work. This allows all the cool dry air from my central airconditioned first floor to fall to the basement and dry it out. This is of course more expensive and not for the long haul. Its only for when I'm going to be down there since my tools rust more from sweat dripping on them then the actual moisture in the air.
VE, I have the very old Sears that rivertoms speaks of in my current family room *(shop annex) and it's been running at max for 15+ years hosed to the sump hole under the house. Here on Long Island we are below sea level and it has done yoeman service. All yhe best, Pat
* I am widowed and live alone -SWMBO WOULD HAVE KILLED ME.
I just went through this with my wife's home office which is in a partially below-ground basement. It doesn't get very hot in there but with all the humidity this year it was kind of damp and was starting to get mildew smelling.
We got a dehumidifier and it did dry things out but is gave off so much heat that it was very uncomfortible in the room. Back went the dehumidifier and we got a small AC unit which was actually much cheaper. It is doing the job very well. It even has a "dry" mode which seems to focus on dehumidificatin and not cooling. Of course the AC needs to be vented outside to dump the heat.
A lot of people run a dehumidifier in their basement but don't spend a lot of time in the basement so aren't bothered by the heat. Just passing along our experience since we just went through this situation.
Lance
Dehumidifiers work best when they're at least a foot off the floor.
"I cut this piece four times and it's still too short."
I bought a sears 50 pt dehumidifier, and it seems to run cool enough in my basement that no A/C is needed. Even on 90 degree days it is only about 75 in the shop. I think if my space were further above ground I would have chosen A/C
I appreciate the tip-Vincent
I live in Monroe City, IN....near Vincennes, and have a totally underground basement shop, with no windows or outside exits, unfortunately. My shop is completely dry, with the use of an old dehumidifier, and a sump pump. Temps are comfortable all year long, without the use of any AC or heating.
Tom
I have used dehumidifiers in all my basement and garage shops for the last 20 years, they work great for controling /reducing humidity. However, make sure you get a basement dehumidifier rated for low tempartures. Better dehumidifiers have a defrost (reverse) cycle like a self defrosting refrigerator, not just an off cycle. Less expensive dehumidfiers use an off cycle which does not work at lower room temparatures. They ice-up, become ineffective, and burnout.
When cutting or sanding, turn off the dehumidifier or it will clog with dust. I occasionally forget to turn it off, so periodically I let it dry out and blow it out.
Thanks for the tip- I just got a kenmore 50 pt. unit rated to 48 degrees. I will not be running it if the temperature is lower than that. Typically the furnace dries the air at that point. I also just purchases 3 gallons of a product called Drylok, which is a paint on moisture barrier for masonry. I'll let folks know how this works after a week or so. Last but not least, I still plan to insulate the space above grade.I am hoping that the moisture barrier will be adequate for the half of the walls which sit below ground level, since the earth itself should provide insulation. This is in part a cost-based decision.
I've used Dryloc, it's a good product. I've also used less expensive products like Walmart masonary paint and Fleet Farm paint made by Valspar. Both those worked just as well and were easy to apply with a roller on a pole. If you use the Dryloc, wetting the wall first really helps spread it easier.
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