When I first built my shop, I had no intention of finishing the interior walls, or if I did, I planned on doing it well into the future. With the drought we have been having, I had never given this a second thought. Now, it is humid as all get out, and water is condensing on the concrete floor to the extent that it is puddling in places. This is not moisture coming up from the ground or a leaky roof; it is coming from the air and condensing. It also condenses on my cast iron tools :( :( It is sooooo bad that I spray WD40 on all the table tops and just leave it. I then clean the tops when I need to use the tools. It is the only way I have found to keep the tools from rusting. It literally takes only an hour or 2 without the WD40 for rust to start!
Right now, I still have some soffit (Sp?) boards to put up and the battens need to be installed on the eves. Will additional 'sealing' of the shop help with this without a vapor barrier in the walls or am I going to need to figure out how to add a vapor barrier, insulate, and finish the walls to get any relief? Are there any other fixes I have not considered?
More vapor barrier and sealing will not help that problem. The only long term solution is keeping the concrete floor and metal objects from getting below the dew point temperature. The only way to do that long term is to heat the shop, even if only to some minimum temperature that will keep everything above the dewpoint temp.
Here in Minnesota, we have that problem in unheated sheds, but usually only in the late winter/early spring when the temps rise and the humidity outside rises with the snow melt. You are right, you can watch the rust grow on bare metal parts. One time I was trying to work under a piece of equipment on one of those days and tried to sweep up the water on the floor. It was condensing faster than I could sweep. :(
You could also try to put in ceiling fans and get the air circulating .
Pardon my ignorance, but is it that humid in Georgia this time of year? What is the average temperature when this is happening? I think sealing the walls and ceiling will help. It take a flow of air to condense that much moisture. With it sealed and a small woodstove it should be ok. Joe
how about a home dehumidfier?
Stonebroke
Had the same problem with my shop in north Missouri at the same time of year that Gary_C talks about. That time is when you normally want to leave the doors open also.
Never did solve my problem as the shop was to big to heat with no insulation and not very tight. I did succeed in keeping the machines rust free by draping a piece of plastic lousily over them in spring and fall. I had another problem as water would condense on the tin roof and drip down...for a few days each spring and fall you might think you were in a rain forest.
Living on the edge of the dessert, it's hard to imagine moisture as you describe. But my shop is wet right now too. It's because I didn't slope the floor, just poured it flat, thinking that is the way a shop floor should be. But I park my truck in there at night, and with all the snow that melts off, the floor is soaked! But my tables are still dry, and my furnace STILL doesn't work. But parts are on the way. Jim
Our humidity today was about 110% :o. Temp about 70. This is only the second time this year that this has happened.
The reason I asked about tightening things up is that it appears to get worse with the doors open. I have fans running in the shop now with the hopes of driving off some of the moisture. Right now, with the absence of soffit, no battens on the eves, and cracks between the lap siding, I doubt a home dehumidifier would help much. I'd just be drying the outside!! I suppose that there really won't be much available in the way of shortcuts. I guess I need to get things tightened up AND get a heat source to keep things just above the dew point.
Mike, I wouldn't worry all that much about the puddles on the floor. Concrete won't rot. My main concern would be the condensation on all those nice machines you have. The only way I know to keep the moisture from condensing on them is to keep them warm. If you can't do that, wax the heck out of them with Johnson's Paste Wax or Trewax. That will keep the moisture away from the metal, and you won't have to clean them before using them. WD40 won't really do the trick, and you don't want that stuff on your wood.
I wonder if anybody has tried using heat strips on their machines. ??? It might be worth a try. They sell them to keep engine blocks warm in the winter, so I guess it would work on a jointer or table saw.
DanG,
I tried the Johnson's paste wax and it didn't work. I did buff after application though. I am sure it would have worked better if I had just left the glaze on and then wiped it off before use. I really clean the tools before use after the WD40 application. So far, no rust with the WD40, BUT I really spray it on heavy. The cast tops are wet with the WD40.
I ought to hook up my block heater to the table saw and give that method a try. It should work fine. I had not thought of that.
RE the concrete. I'm not really worried about the concrete; it is the tools like you mention. I also just can't warm up to the idea of water on my interior floor! Of course, it will be some time before I can do much about it.
It might be enough to just put a light bulb under each of those cast iron beds. Ya just gotta keep them warmer than the dew point. If it works, that would probably be your cheapest out. Actually, I'm pretty sure a 60w light underneath and a tarp over the top of each machine would do the trick. Get a mop for the floor. :D :D
Brdmkr, I know you ain't gonna want to hear this,and I hope I'm wrong but here goes anyway. Most likely the problem is your concrete floor. Sealing up the building will only make the problem worse. Concrete is not impervious stone, it's actually pretty close to limestone which will soak up water like a sponge. If you didn't lay down a water barrier under the concrete, any moisture under the slab will wick up through the concrete, then evaporate until the humidity gets so high you get condensation on everything. Sealing the concrete floor might help.
Extruded polysyrene foam , XPS, or blue board. cut to fit a little bigger than the table top. keep the top waxed and always put the foam on there when not in use.