Pole Barn Roof Question

[recout]

I am going to have a 24x32x10 pole barn built. I was going to use a metal roof with a ridge vent. Also with 12" vented eaves. I was over a buddy's house and talked about the pole barn. He told me that his friend has a pole barn with a metal roof that has a moisture problem in mostly the summer. Has anyone had a problem with a metal roof and moisture build up on the inside of the roof? Would it help if there was a wood roof and ashalt shingles

 

[SARG]

I have a 30x60 pole barn of all metal roof and siding. A couple times per year during the summer months we will have condensation forming under the roof panels.

I figured it's part of the program .. just like the mold that has to be scrubbed off the siding every couple years.

 

[lucky llama]

If you put a thin layer of insulation under the metal you should not have condensation problems.

 

[Craig Clayton]

I have an uninsulated pole barn. The condensation is a function of the weather, humidity and where you live. You do what works in your area.
Craig Clayton

 

[dweitzel]

Spend the money and put the insulation in. 3 to 4' wide and 1/4" thick.

The ridge vent should take care of most of the moisture. The remaining condensation will either not form because of the insulation, or will run out between the end of the metal and insulation. JMHO

 

[Duffster]

7/16 OSB will be enough for a condensation break.

IMO condensation issues are kind of blown out of proportion.

 

[teg]

...IMO condensation issues are kind of blown out of proportion...

...Have you had it rain inside yours???

 

[Duffster]

...Have you had it rain inside yours???

Only in sheds full of livestock.

 

[teg]

I guess I do have a mouse problem... anyway, I guess I try insulation (give the mice a place to call home).

What if there is a barrier with 6" of space? At least the drops would run to the sides...:confused2: anybody try that? I was thinking tar paper...

 

[johnrex62]

That much condensation also sounds like poor ventilation may be a factor. Airflow under the roof will dissipate moisture and reduce condensation. Simply adding insulation to the underside of your roof may just trap the moisture between the metal and the insulation and create a mold colony.

 

[Johnbro]

We have two buildings with metal roofs (I built one of them). Both use an insulated blanket that goes under the roofing and on top of the framing. Just lay it in place and screw down the metal roof on top. Makes a nice white finished look inside and keeps the condensation off. Did I mention cheap?

 

[Willl]

I have a 24X36 pole, it's only insulated on the under side of the roof.

Doesn't sweat and doesn't feel humid, never has. My tools say the same.

Edit; mine sounds the same as Johnbro.

 

[teg]

That much condensation also sounds like poor ventilation may be a factor. Airflow under the roof will dissipate moisture and reduce condensation. Simply adding insulation to the underside of your roof may just trap the moisture between the metal and the insulation and create a mold colony.

Yes, I'm sure that poor ventilation is most of it. The only time it's a problem is after condensation freezes over night and the sun hits it in the morning. The beads of water roll down to the strapping and collects into droplets. Happens for 5 minutes and it's done...

 

[recout]

What does everyone think about a wood roof with shingles with a ridge vent? think that will help with the moisture problem? Or will the wood just soak up the water?

 

[tommu56]

I had my builder put tyvek under the roof on top of the purllins and haven't had an issue with condensation.
I do have ridge vent and 12" sofit all the way around including the gable ends.

tom