Will I have condensation problems?

[OldBarn]

I'm considering moving to Virginia and building a very large metal building, probably 60x100 or so, and very tall - 30-40 foot eves. What I would like to do is build a big cheap shell and slowly finish it off inside. I only want a 30x60 shop area that will be walled off and insulted. Lots of other insulated rooms for other things. The rest will be unheated.

I currently have an old wood barn about this size (a little smaller), in Oregon. It is not insulated, but has wood siding and 3/4" boards lining the inside walls. It is not sealed and very drafty. It gets very humid inside this time of year, but I never have condensation on the walls or anywhere else.

I'm worried with a big uninsulated steel building I will get a lot of condensation inside. Is this going to become a problem? Can I leave half or more of the building uninsulated long term?

Am I crazy to think I could run a dehumidifier in a space that large? I can't use one now because my barn is so drafty, but I want the new building to be sealed up tight.

 

[RegularJoe]

I think you're likely to get condensation without any insulation/vapor barrier and yes, you're dreaming to think an dehumidifier would solve the problem.

 

[OldBarn]

Is a vapor barrier needed on the walls? I will most likely try to do a full concrete slab with a vapor barrier.

 

[kd3pc]

you will still need a doozy of a ventilation system...on a sealed building, even more important. and depending on where in VA you build, humidity will vary from 50-100% and the temps can easily hit the 90s for days on end. I lived in Roanoke and kept my boat in Callao, and many times it was more humid in Roanoke than on the boat.

A large HVAC blower can be used to move the air, but you will still have to deal with the humidity.

Vapor barrier is a given.

 

[larry_g]

I have two buildings here in the valley that I used this stuff in, http://metalbuildinginsulation.com/index.html . I did all the ceiling and wall in the 2" material sandwiched between the purlins and metal siding. I have no moisture problems in either building. Your welcome to stop by if your in the Salem area.

lg
no neat sig line

 

[OldBarn]

I have two buildings here in the valley that I used this stuff in, http://metalbuildinginsulation.com/index.html . I did all the ceiling and wall in the 2" material sandwiched between the purlins and metal siding. I have no moisture problems in either building. Your welcome to stop by if your in the Salem area.

lg
no neat sig line

Any idea what that stuff cost per square foot? My problem with that is it has to go on before the metal siding. I can't close in the building and then add it next year. Sure would be nice though. I used to have a smaller building that had this stuff, and it never sweat either.

Trying to keep my costs as low as possible, so I don't have to get a loan. Maybe I'll just finish the back 30 feet and go from there.

 

[OldBarn]

A large HVAC blower can be used to move the air, but you will still have to deal with the humidity.

I definitely want to have ceiling fans throughout. I don't want to have to burn a ton of power just to keep things dry though. Part of the reason for the height of the building is to let the heat rise and hopefully keep the lower level cooler. The building I have now is very good at that. I will be building a 3 story mezzanine type structure inside.

 

[larry_g]

Any idea what that stuff cost per square foot? My problem with that is it has to go on before the metal siding. I can't close in the building and then add it next year. Sure would be nice though. I used to have a smaller building that had this stuff, and it never sweat either.

Trying to keep my costs as low as possible, so I don't have to get a loan. Maybe I'll just finish the back 30 feet and go from there.

No I don't have a cost. Both buildings it was part of the total. last kit came from http://www.mwbsc.us/mwbsc_res/mwbsc_new4/index.html . Give them a call and ask. Good luck with your new adventure.

lg
no neat sig line

 

[HAP]

WTH, 30-40' eaves??!!

 

[OldBarn]

WTH, 30-40' eaves??!!

I'm going to build a 2nd and 3rd floor mezzanine in some areas. It's not all that common with backyard shops but is pretty common in old barns. It doesn't cost a lot more to make the building taller. The barn I have now stays about 15 degrees cooler on the first floor than up on the third floor on hot summer days. The inside structure will be free standing from the building, and like the insulation, as I get around to it.

I'm looking at over 15,000 sq ft when I'm done. He who dies with the most **** wins!

 

[CADPoint]

You might consider a 4' whole house fan in the "A" frame?

Where ever your moving you might want to check with the county
that your moving into.

While in VA, you allowed to construct a house under your own permit,
what you suggest might be beyond that scope of a personal permit.

Things are quite a bit different east of the Mississippi when it comes
to permitting.

 

[OldBarn]

You might consider a 4' whole house fan in the "A" frame?

Where ever your moving you might want to check with the county
that your moving into.

While in VA, you allowed to construct a house under your own permit,
what you suggest might be beyond that scope of a personal permit.

Things are quite a bit different east of the Mississippi when it comes
to permitting.

I'm thinking about some kind of cupola structure on top, might help vent even better in the summer. I'll definitely need to look at the codes, though I'm looking for several acres way out in the country. A lot of places do have height restrictions. As far as the county is concerned, I'm building a big hollow ag building.