pole barn ridge and soffit insulation question

[dnroe]

Should metal building insulation be ran up and over the ridge in a pole barn or does the ridge need to be vented?

What I have is a 24'x36' pole barn with metal screwed directly to the wood purlins. This weekend I will start taking off the old roof and replacing with new metal and adding 3" thick metal building fiberglass blanket while I am at it. I hope to insulate the walls the same way a little later this year. Building is mostly a workshop and I spend an hour or 2 a day working in it. Just trying to help with condensation and keep it a little warmer with the heater running.

I do not have a vented ridge so I am thinking it would stay warmer to just run the insulation all the way through. The building does not have a ridge beam so if it needs to be opened up I will have to stop the insulation at the two highest roof purlins which would leave about a 1' gap the full length of the building The building will not be very tight as I have two large uninsulated rollup doors that are a little drafty.

Also should I leave the blanket a little long on each side and tuck a few inches between the side girt and the sidewalls?

Thanks for any suggestions

 

[kevin206]

I have a building about the same size, insulated about the same way, and with the drafty roll up door. I'm not vented anywhere. It does okay on the winter, but it gets really humid and musty smelling in the summer. ..but I may only get in there once a week or two. For my purposes, I would prefer tight sealed with a powered ventilation system. I don't think the insulation would help you if all your heat went right out a ridge vent.

 

[dnroe]

Thanks for responding Kevin that makes me feel a little better about it. I am usually out there about everyday and open up the big doors in the summer with a large fan running. Hopefully humid won't be a big issue. I did think about running a dehumidifier when needed once I get it sealed up enough to be effective. Might even try the diy trick using a large bag of salt hanging above a bucket

 

[bluejack]

I'm in the same boat. About to use metal building insulation on a wooden pole barn about R13 (3-4") and screw the roof directly into wood purlins. It's vinyl backed and my contractor buddy seems to think that will work fine. I wondered about moisture problems but I guess this is done all the time on metal buildings....

Contemplating going this route or closing in my trusses and blowing in insulation...Seems like the sandwich between roof and purlins would be much easier.

Any other opinions out there for me and dnroe?