s/o metal roofs: vapor barrier, insulation, etc....?

[dmalbone]

I'm a little clueless when it comes to what goes under the roof as far as vapor barriers, etc. We have 2 ridge vents and a cupola, so the actual ventilation is ok. My "barn guy" told my mom when she was building her that one of the darkest colors needs a vapor barrier underneath it because of something. I'm not going to lie... he's over 80 years old and he's very hard to talk to because a single innocent question turns into a HUGE hour long convoluted story. :lol: When I told him we were doing ridge vents and a cupola and asked if we needed a vapor barrier still he said no, not unless we were doing one of the darkest color roofs. At that time we weren't sure on color. So now I'm confused on what people normally have underneath theirs. What do you have and why (if you know!)? Is insulation different than the vapor barrier? Without insulation or a vapor barrier do you think I'd have problems in the summer or winter with a charcoal colored roof?

[2DogsFarm]

Hmmm...my barn roof is dark burgundy.
I have the ridge vents but no cupola (forgot it in the planning stage and aftermarket is a Bear!).
I have foamcore insulation in the barn roof to avoid condensation.
Horse bodyheat + closed barn in Winter can = drippage into the stalls and elsewhere.
I don't know/can't recall (shame on me) if there was a vapor barrier placed under the foamcore.
Guess I could go look up the plans and get back to you on that.

The indoor is not insulated and there's not a whole lot of condensation even in the dead of Winter.
But arena is 16' at the rafters, barn is 10' - that may mean the differnece plus no horses stabled in the arena.

I don't recall color - aside from personal preference - being an item for discussion when I was working with the builder.

[avezan]

I have a white metal roof and the foam core insulation. I LOVE the insulation, no dripping. It was well worth the extra price. I have a ridge vent and cupolas. We never discussed a vapor barrier so I'm not sure what that is.

[Calvincrowe]

I have a white metal roof on my barn, no insulation (don't really need it here) but I do have a vapor barrier. Pretty sure it is similar to Tyvek that they wrap houses in. I don't think it is very expensive, and it was installed when they put the roof on. Keeps dripping to a minimum when it has rained incessantly for weeks on end here, and my barn is as humid and drizzly inside as out.

Down side? Starlings LOVE to nest inside insulation or vapor barrier material, so if it gets torn or saggy, they will take advantage.

[2DogsFarm]

Down side? Starlings LOVE to nest inside insulation or vapor barrier material, so if it gets torn or saggy, they will take advantage.

I can vouch for this - it is Starling Metrocenter under my barn eaves :(
But the little ba*t#rds destroyed the foamcore themselves - I kept finding piles of chewed foamcore on the ground in the corners & looking for responsible mouseholes at ground level. Then I looked up :mad:

[sixpoundfarm]

I have a tan metal roof on my barn, and we do have ridge vents and non working cupolas. I did opt for what the builder called vapor barrier/insulation. It's a thinner silver material, kind of like bubble wrap I think. It prevents condensation inside, so I don't have dripping or those water lines on the purlins from moisture. It also keeps it little quieter during heavy rain.