Barn floor SOAKED....

[HunterDan]

So I'm obviously having an issue right now, and I'm hoping its solveable.

It was really nice here in md today (65ish), so I decided to change the oil in the truck. I got home from work, opened up the door to my pole barn, backed in and got out.

The entire floor had a "film" of condensation on it. And under my golf cart was a puddle, where it was dripping off the frame of the cart. It's been about 2 weeks since I've been out there, and it was dry then.

This past weekend, the lows were 5-10 and highs in low - mid 20's. Then yesterday it was about 50, and today the truck said 67 when I got home. Now I know that's a recipe for condensation. But the barns almost a year and a half old, and I didn't have any issues until now. The stuff I have in the barn feels dry to the touch, it's basically all on the floor.

The barn is 40x48x16 with metal roof/siding. All vented soffit and full length ridge vent. The floor is a stone base, vapor barrier, wire and 6" concrete topped with nohr s polyurea. The floor cured for 8 or so months before any coating was put on, so I'm sure this isn't my problem. The interior is all open right now, no insulation or anything.

Could it be that it was so cold for a few days, then got so warm so fast? Or do I have another problem?

Or am I

 

[lakeroadster]

Could it be that it was so cold for a few days, then got so warm so fast?

That's the problem. What's the humidity there today?

High humidity, quick temperature change from cold to warm... equals drippy barn.

It really is amazing how quick the condensation will form. The soffits and ridge vents let all that warmer moisture laden air circulate through the cold building, then anything the air touches that is below the dew point ends up with moisture condensing on it.

I used to have the same issue when I lived in Ohio. I'd open a drawer on my tool chest and the tools would be covered with moisture.

 

[HunterDan]

I'm not sure if the exact number but it was humid. Should I put some de humidifiers in there to help dry it up?

 

[lakeroadster]

That would take some huge dehumidifiers.

Do you have insulation under the roof sheathing? That's a huge help.

I'm in the process of designing some hinged polyiso insulation covers for the soffit vents and ridge vents of the heated area of my barn.

All that air flow is great in the summer... and problematic in the winter.

 

[HunterDan]

Yea I kinda figured....

No I don't have anything in there, it's all open, bare metal facing the inside

 

[HunterDan]

If I put up 1/4" fan fold insulation over the purlins, do you think that will help things until I can afford to fully insulate it?

 

[bigjon]

My shed did the same thing last winter under similar conditions. I think the floor coating made it noticeable due to the moisture not being able to be absorbed by the concrete.

(Cold floor + warm, humid weather)/coated floor = wet floor

 

[foompla]

Running a heater to reduce temp differential between moist air and cold floor would help

 

[jives]

Yesterday the temps hit 50 and rainy after many frigid days. Condensation on the cold concrete floor. Used a 3' squeegee. Works great.

 

[lakeroadster]

If I put up 1/4" fan fold insulation over the purlins, do you think that will help things until I can afford to fully insulate it?

Yes it will help.... but that's going to be a lot of work. What's your long term plan, a ceiling at the lower truss chords with insulation or ???

 

[theoldwizard1]

You have a high water table do to freeze/thaw. Humidity is not going to make puddle.

My French Drain and Dry Well Project

 

[lakeroadster]

You have a high water table do to freeze/thaw. Humidity is not going to make puddle.

Water table? You mean like for a well? How is that relative?

Condensation from humidity will indeed pond if it is on a sloped surface.

 

[Jeepster04]

It will continue to sweat until you get it closed in and sealed up. As others have said, everything in the garage lags behind in temperature when the temp outside makes big swings like that. Its just like the mirror or toilet in your bathroom when you take a shower, exact same concept.

Even my garage in my house will do this. Its sealed up, insulated, and I keep a dehumidifier running on automatic (65%). If its been cold outside, then quickly warms up and rains, when I open the garage door the concrete floor and the vehicles inside pretty much immediately condense. When it does this I try to close the door back quickly since I dont like my vehicles that I keep covered up in there to condense. If I kept the garage heated more than I do this wouldnt happen since all of the surfaces in the garage would be above the dew point.

As for the foiled backed bubble wrap, etc, on the underside of the purlins, that will only keep the underside of the metal from sweating. It keeps that warm moist air from hitting that cold metal and condensing. This typically only happens in the cool mornings when the sun first pops up or the temp quickly rises. The metal lags behind the air temperature for a short period of time and thus.... condensation forms!

This has been happening a lot here lately. Weather has been pretty crazy so this is probably happening more often than it normally does. A week ago it was 10F here for several days in a row and it was 68F yesterday with rain. Its actually giving rain everyday for two weeks, which is crazy for this time of the year. Today its 35F, three days from now its giving 60F again... With more rain....

 

[theoldwizard1]

Water table? You mean like for a well? How is that relative?

I probably used the wrong terminology. In winter especially after a hard freeze, then a mild thaw and rain, water will be trapped near the surface. A French Drain at least 2' deep will solve the problem.

Bottom line, it would take a TREMENDOUS amount of humidity to get it to participate out into standing water.

 

[MagKarl]

I'd try some fans and see if that helps any. There's no amount of insulation that's going to fix the problem of a cold slab and a rapid weather change to warm, moist air.

 

[Radix2]

I'd try some fans and see if that helps any. There's no amount of insulation that's going to fix the problem of a cold slab and a rapid weather change to warm, moist air.

This is the answer.

If a surface is below the dew point of the air, water will condense on it. Nice cold beer can, glass of water, toilet tank... whatever.

Doesn't matter if the place is insulated to R-100, let that moist air in against your cold floor, it is going to get wet.

So.

-Don't let the outside air in.

-Heat the place so the floors are above the dew point.

Those are the only solutions. Period.

And the floor coating does make it much much worse, plain concrete just absorbs the dew and darkens.. a coated floor gets wet.

 

[Radix2]

This problem is another great feature if radiant floors - you can keep the floors idling along at 60 in the spring for very little, so that when you open up in the morning they are above the dew point and everything stays dry.

 

[HunterDan]

Thanks for all the tips!

My future plans are to insulate the walls with batts, vapor barrier, then 1/2" plywood for inside sheathing. The cieling will probably be blown in, vapor barrier, then metal cieling.

It will probably be a while until I can get that, as I want to build my mesanine, and wire the place up, before I do insulation.

So I'm pretty much **** outta luck and have to deal with this until I get it insulated?

 

[bigjon]

Thanks for all the tips!

My future plans are to insulate the walls with batts, vapor barrier, then 1/2" plywood for inside sheathing. The cieling will probably be blown in, vapor barrier, then metal cieling.

It will probably be a while until I can get that, as I want to build my mesanine, and wire the place up, before I do insulation.

So I'm pretty much **** outta luck and have to deal with this until I get it insulated?

Mine only did it during those abnormal winter weather events when it got warm and humid suddenly. I'm predicting it will do it once or twice next winter. Doesn't happen in summer. I live in a temperate climate.

 

[pop pop]

In winter, minimize the air into the building. In summer, just the opposite. If it's been cold, don't open doors and let air in.

 

[RedPentacleB]

I have almost the same scenario, including the Nohr-S. Insulation likely will not help. The problem is that the slab is colder than the "dew point", so you will get condensation. The water will sink into an unsealed concrete slab, but the Nohr-S seals so well, the water stays on the surface. It can get quite slippery too. In my case, I had PEX tubing installed during the pour, so the slab can be heated. I think you have limited options. You could grind off the coating so that the condensation could sink into the floor, or you could heat the floor so you don't get condensation. A not-useful suggestion would be to refrigerate the air to make it colder than your floor ;-)

 

[theoldwizard1]

None ever believes me, but I still think your problem is that OUTSIDE surface water is not being carried away fast enough.

 

[yhprum]

You can minimze this by putting some plywood under the car. Used to happen all the time where I grew up. The fan wouldnt hurt either.

 

[Pig9r]

Just like taking a cold beer out of the fridge on a hot, humid day. All of that moisture is coming from the warm air. Completely normal when you have 50 degree temp swings from one day to the next. Everything inside cools down but doesn't warm up as fast as the outside air. Nothing you can do other than keep your barn heated or open it up more so that things equalize slower or just keep everything closed to limit the amount of warm air coming in. I have an old Ford tractor and all that old iron really holds the cold. On days like you described it looks like it is raining underneath it. There is a signicant difference between the surface of the tractor and the ambient air temp.

I plan on installing a couple ceiling fans in my barn and will keep them going to see if that helps the issue.