moisture in metal building

I had an 18X20 metal building erected on a sand rock floor in February 2007. I expect it"s as dry inside now as it"ll ever get. Still anything left on the floor gets wet where it touches the floor and I often see moisture on the inside of the building and the contents of the building. Any inexpensive ideas on making it a better place to store stuff? I"ve thought about increasing ventilation by putting maybe a 2 foot square louvered vent in the back up at the peak. Perhaps also add a couple smaller louvered vents at ground level on the sides at the font corners. Comments?
My building

Think you have the right idea but I wouldn't overdo it. Couple of small slots along the bottom of each side and one in each peak should do it. If you've got an old (or cheap) kitchen exhaust fan to connect to one, you could turn it on in bad situations. Something like the foundation vents that you put in place of a block will keep out the boogers.


Dave

the only way to stop condensation is to lay down heavy mil plastic defore doing the floor and to insulate the walls. i sell them in south carolina and that is a common problem with all steel sheeted buildings. good luck you might try to glue up the blue foam board to the walls and the roof.

ricky c is 100% correct; plastic under the floor will keep the building dry and it will not sweat.

Rick & Dean made a good point, but I don't agree 100%. We many times do put plastic under floors if there is poor drainage. We kind of have better luck if we use dry sand under the slab and keep it dry. Plastic will stop wicking, but if you have dry sand under the slab it will draw the moisture away.

I feel you can do anything you like, but if you don't have insulation, and heat the building you will always have some issues with moisture. Not practical at all, so ventalation is the next best idea. If you ventalate you move the moisture in the air flow.

To make my point grab a glass of ice water and watch it sweat as it hits warm air. You can not stop this process with a moisture stop. Your concrete and building will sweat as you have seen.
Another example is grab a chunk of frozen steel and carry it inside the warm house--again sweating will happen.

Now if you put your ice water inside a insulated class you have no condensation, or only a little.

If it is a option when you hit those certian days you can just open every door and it will help. Again not practical at all unless you work inside the building every day.

Your options are not jackhammering out the concrete anyway, so ventalation is your best option, and as another person said try the little options first before powering up a big fan etc. Yet we all know if you mop the floor in your kitchen and blow a fan on it you can cut the time it takes to dry the floor.

In our area if you have a metal building that is not insulated you will get a wet mess on certian days---interior rain storm.

Good luck, and I hope I did not offend anyone.

Thanks to everyone. Water around the building is controlled pretty good. If I had to do it over again I'd probably put down plastic before the sandrock I have as a floor. I was too cheap for concrete. I kinda splurged for the building itself. It's just for storage of my long time neglected project tractor and other similar items so they're locked up and I can put the car and truck under the carport. I have an attached garage that always seems to have something disassembled in the floor and I've given up on using it for parking the car.