Hello everyone,
My name is Lou, I’m new to this group, but a vetern of many other formums. I’m in the process of setting up a basement shop in an area approximately 15′ X 30′. I live in the Northeast and it gets pretty humid around here this time of year. So far I’ve sealed the basement walls with waterproofer and sealed the concrete floor with Thomson’s Water Seal.
I should say that the basement is normally dry and well insulated – it stays about 60 degrees years round. Here’s my question: I have a set of double door leading out to the yard. Yesterday I had them open and within about an hour I could really feel the humidity. The concrete floor darkened up as the water vapor sat on top of the sealed surface. Now I’m woundering if I made a mistake by sealing the floor – the original intent was to keep the dust down.
Obviously the high humidity won’t be good for my tools. I was wondering if I keep the doors to the outside closed and run a dehumidifier I can keep things dry? Any advice or past experience is greatly appreciated.
Thanks,
Lou
Replies
From the way you describe it, I would think a dehumfiver would do the trick. We use 'em here in Florida on closed up yachts all the time to keep the mildew down. My garage shop (door usually open) here in Florida is not airconditioned nor do I have a dehumifiver. Only my Japanese saw blades rust badly, so I put 'em in plastic bags. The real rust problem is sweaty hands. Otherwise a little wax keeps the cast iron clean.
Dave
Lou,
It's pretty clear about your goal to keep your basement shop at low humidity. But some o fthe things you described are puzzling.
First, sealing the floor and walls will do nothing about atmospheric humidity. If the air is humid, you'll feel it everywhere in your home, including the basement. Sealing the concrete floor will keep concrete dust down, but I don't think that Thompson's will do the trick. It will wear through very soon. There are concrete coatings - epoxies - that are much better.
What do you mean that the concrete floor darkened after you opened the doors and that water vapor sat on the sealed floor. Do you mean that the 60 degree temperature of the basement caused condensation on the cool floor? Were the walls wet with condensate?
If you noticed the atmospheric humidity after an hour of having the doors open, you probably were actually noticing that your basement temperature was rising as the outside air heated the room. The atmospheric moisture permeated the room even before the doors were opened.
Yes, a dehumidifier will keep the basement dry. But you will need to seal all openings well, if it is to be effective. Also, it will propbably need to run it almost 24 hours a day if you really want to keep things dry. You will lose all the advantages of the unit if it gets humid for a few hours of any day. And dehumidifiers are expensive to run.
You can keep ahead of any serious rust problems by waxing, oiling, covering equipment (especially horizontal surfaces), keeping tools in closed cabinets and chests, tool rolls, etc. And oh, yes, by USING your tools.
Rich
I have a shop that is above ground on a concrete floor with stud wall covered with t-111 siding. The first piece of equipment I bought was a table saw with cast iron wings. Of course I started experiencing rust on the saw table. I tried the Boeing product. That was useless. I tried turtle wax. That was better, but the problem was still there and I had to wax frequently. (I guess that would depended on useage of the machine). Anyway, it was frustrating and my major concern was what was occuring on the inside of the machines. I would cover them when not in use, but I discovered after a short vacation trip that the rust was back. As you did, I ask on knots about dehumidifing. I got very tepid responses. Some were even very sarcastic.
But I decided to insulate and dehumidify my shop anyway. WHAT A DIFFERENCE. I don't cover or wax any more. And I don't worry about the inside mechanisms on any of my tools. Hand tools and power tools stay very nice and rust free. I keep the RH @<60. and I keep my dehumidifier running 24/7 unless the shop is open. I have not had to wax anything to prevent rust since. I open the shop when the outside RH is < 50 just to change the air around. And keep it closed when the RH is >50. Any difference in my power bill is negligible.
I would highly recommend that you dehumidify your shop.
Dave
I will second what Dave said. I live in Massachusetts and it gets pretty humid at this time of year. A couple of years ago, I bought a dehumidifier from Home Depot (Hampton Bay - about $200). I keep it running all the time during the summer, and I take out a full basin of water every other day. I have not had any problem with rust on my tools. Like Dave, I have also not been aware of any significant rise in my electric bill.
My basement is in an old house (circa 1917), and I only did minor sealing on the walls. The floor is untreated concrete.
I also occasionally do a treatment of Top Coat on my tools for a nice friction-free surface and to help prevent any possibility of rust.
I would say you definitely should get a dehumidifier.
I've had the same experience as Matt and Dave. I have an old house with my shop in the basement. I developed rust at first, then I put in a dehumidifier and it stopped. My dehumidifier has an electronic humidistat and I attached a hose that runs into a floor drain. I just set it at 40-50% and forget about it.
Here in Las Vegas, we have very little humidly, but I had a shop in the Pacific Northwest and got used to waxing all my machinery with Johnson's Past Wax. I still use it here. It, not only keeps the moisture off the tools, by keeps them looking good. I also wax my outfeed and extension tables on my table saw. Even heavy plywoods such as oak, birch, and melamine slide easily.
Len (Len's Custom Woodworking)
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