Posted 2010-11-28 8:54 AM (#127515) Subject: barn sweating
Regular
Posts: 51
Location: Edwards Ms
Need a little input please....My husband and I finished our barn this past spring (well it's actually a work in progress) and we are really very proud of it. It is 36x48 5-10x12 stalls with a 12 ft open aisle, wood siding and a tin roof. Now to my problem!!!these cold mornings and its like its raining inside the barn. Been racking our brains about how to fix the problem and the only thing we can come up with is to take the tin off and laying some type of barrier on top of the purlins. I really,really don't want to do that................but I don't want my purlins to eventually rot either. Any ideas would be appreciated.
Posted 2010-11-28 9:11 AM (#127516 - in reply to #127515) Subject: RE: barn sweating
Elite Veteran
Posts: 824
Location: Kansas
You can look into a sprayed on insulation that should stop that, but my barn is over 15 years old and no trouble yet, although I do have the condensation. I don't have any wood to rot though.
Posted 2010-11-28 10:46 AM (#127519 - in reply to #127515) Subject: RE: barn sweating
Extreme Veteran
Posts: 447
Location: cedar rapids iowa
Do you have a ridge vent and the soffits vented. What caused the condensation is a warmer temp inside than outside. Proper venting should eliminate most of it. I have never been dripped on in my metal building.
Posted 2010-11-28 11:26 AM (#127520 - in reply to #127515) Subject: RE: barn sweating
Expert
Posts: 5870
Location: western PA
The warm moist inside air is rising and touching the cool metal roof. The air condenses upon contact, and the moisture falls out of suspension into the droplets you see. The only cure is to insulate the bottom of the metal so the air can't directly contact the metal.
As was previously stated, spray insulation works very well. Another less expensive DIY is to purchase rolls of foam insulation; cutting and stapling it between your rafters. It is inferior to the spray insulation as an insulation, but will work as a vapour barrier and stop the condensation.
Posted 2010-11-28 1:11 PM (#127525 - in reply to #127520) Subject: RE: barn sweating
Regular
Posts: 51
Location: Edwards Ms
as far as venting, my barn is wide open it's just as cold inside as out most of the time so I really don't think venting it is the problem. And yes Gard I think my problem is when the sun shines on my roof it's forming condensation on the underside. I think what I really am asking is if I just put a vapor up there without putting it between my purlins and tin do you think it would rot my purlins over time. Will the condensation still form between the tin and the purlins?
Posted 2010-11-28 3:04 PM (#127531 - in reply to #127525) Subject: RE: barn sweating
Extreme Veteran
Posts: 447
Location: cedar rapids iowa
Mine is wide open also but vented at ridge and soffit, not insulated and I do not have this problem. The heat gets trapped up high as it rises and if it is not vented it can't escape. The soffit vents keep air circulating up through the ridge also.