Pole barn air gap insulation

[cayturbo]

Hello all. I have a 60x68 pole barn I am getting ready to insulate. I had the cheap "bubble" insulation put in when it was built but am getting ready to frame the walls with 2x6 24" OC and install R19. However, I was wondering if the existing 2x6 horizontal beams that I will putting my framed in walls against will create an undesirable air gap. My worry is that as the insulation goes around the horizontal beams it will create a slight air gap which will lessen efficiency for me (picture attached). And of course there will be some air gap behind the 2x6 studs and the existing bubble insulation. I can do my best to fill this in with the insulation as I install it.

Am I overthinking this? Foam is out for us as option for a couple of reasons so I'd like to proceed on this path as long as I'm not making a boneheaded move. Thanks all!

 

[astroracer]

You are over thinking it... There is insulation (bubble wrap) on the outside already, you will be insulating with faced batts inside of the 2 x 6 girts. Any "airgap" behind the new insulation is not going to affect it's efficiency. It may improve it though as that airgap will prevent contact (and thermal transfer) between the inner and outer insulations... There is nothing to worry about here so you need to get busy.
Mark

 

[Jking24]

Hello all. I have a 60x68 pole barn I am getting ready to insulate. I had the cheap "bubble" insulation put in when it was built but am getting ready to frame the walls with 2x6 24" OC and install R19. However, I was wondering if the existing 2x6 horizontal beams that I will putting my framed in walls against will create an undesirable air gap. My worry is that as the insulation goes around the horizontal beams it will create a slight air gap which will lessen efficiency for me (picture attached). And of course there will be some air gap behind the 2x6 studs and the existing bubble insulation. I can do my best to fill this in with the insulation as I install it.

Am I overthinking this? Foam is out for us as option for a couple of reasons so I'd like to proceed on this path as long as I'm not making a boneheaded move. Thanks all!

The biggest thing you want to do before framing is get what's already their air tight as possible if their are any obvious air leaks address them. Insulation is all based on zero air flow. And air leaks not gaps negate the undulations effectiveness

 

[ArtisanFarms]

Depending upon your location, you may have an issue. The concern is the potential for condensation in your air gap space. If the bubble insulation is sufficient to ensure that you will never have condensation on the interior, you're fine. If you do end up with condensation, it can start to wet your fiberglass and girts and potentially lead to mold and/or rot. Honestly though, the risk is probably very low.

The Green Building Advisor has some good articles on designing walls with two layers of insulation with an air gap between the layers.

 

[jvitez]

Where are you located? Check out this Climate Zone map and tell us which zone you're in. That will clarify whether you need a vapour barrier and where it should be.

https://www.greenbuildingadvisor.com/article/climate-zone-map-including-canada

Personally I wouldn't want the air gap created by your girts for exactly the reasons mentioned.

I would fill in the space between girts with 1.5 inch thick EPS foam sheets (expanded polystyrene, not XPS or extruded polystyrene), as EPS won't act as a vapour barrier, and you'll add about R4.5-5 to your wall. Then fill in the rest of the space with batt insulation.

Also, please check out Rockwool insulation.

https://www.rockwool.com/

It's water impermeable, critters don't like to live in it, and it's fireproof. I've insulated two garage/shops with it. Fibreglass is actually a rather mediocre type of insulating material.

 

[cayturbo]

Thank you all for the responses! We are located in Zone 3--South Carolina.

The existing bubble wrap insulation is extremely tight and unmovable--there are no current issues with condensation. So we should be good to go?

 

[Hubmonkey]

I live in OK and have no issues with Condensation. I have the same foil faced Bubble wrap done in mine. I did not really know what I was asking for when it was built as it was my first time getting one built. I framed in 2x4 walls between the poles and filled with craft faced insulation then sheetrock.

Hub

 

[cayturbo]

I live in OK and have no issues with Condensation. I have the same foil faced Bubble wrap done in mine. I did not really know what I was asking for when it was built as it was my first time getting one built. I framed in 2x4 walls between the poles and filled with craft faced insulation then sheetrock.

Hub

Looks almost exactly like my setup! Is the insulation as installed working well?

 

[Hubmonkey]

I just work out there on occasion and just keep it above freezing on really cold days when I am not out there. If I am in the shop I have the mini-split going but don't try to keep a constant temp. For me it works well. For the roof I used vinyl faced insulation between the rafters. It is 4 ft wide and I used strapping between the rafter for support.

Hub

 

[cayturbo]

Question for you guys who have done it this way. I've had a couple companies out to give quotes on installing the insulation once I finish the framing. One didn't mention anything about the ceiling insulation needing covering (e.g. particle board or plywood), he just said it could be stapled up. And this same guy also would use unfaced batts in the walls and didn't say anything about needing a cover to keep it in.
Another company said the ceiling insulation would start to fall out within a month or two if I didn't cover it with some sort of (e.g. plywood) and also said the batts in the walls would start to fall out in 6 or so months as well if there wasn't anything there.
Anyone have any insight to this? I guess it makes sense in some way, but hadn't really given it a lot of thought!

 

[astroracer]

The fiberglass batts will start to sag very quickly. The Kraft faced batts will have some "hold-up-ability" but they will sag in a short time as well. They should have something to support them, don't rely on the staples to do that.
Mark

 

[cayturbo]

Awesome, thanks. I suppose any sort of very thin particle board would work?

 

[Hubmonkey]

If you look at the picture I supplied you can see that I used strapping to provide support to the Vinyl Faced Fiberglass I did on the roof. It is Gray in color. My trusses are 4 foot on center and that is pretty wide so stapling it up there alone was not an option. I looked around for Steel strapping and could not find any local and the price of it varied wildly online so I used what the HVAC folks use to hold up ducts in homes. Figured if its good enough for that it would be fine for my needs. If all else I can just get some wood strapping and use that. I did not want to add any weight to the trusses than I had to so a ceiling was a bit much for me to handle by myself.

Hub

 

[cayturbo]

If you look at the picture I supplied you can see that I used strapping to provide support to the Vinyl Faced Fiberglass I did on the roof. It is Gray in color. My trusses are 4 foot on center and that is pretty wide so stapling it up there alone was not an option. I looked around for Steel strapping and could not find any local and the price of it varied wildly online so I used what the HVAC folks use to hold up ducts in homes. Figured if its good enough for that it would be fine for my needs. If all else I can just get some wood strapping and use that. I did not want to add any weight to the trusses than I had to so a ceiling was a bit much for me to handle by myself.

Hub

I see that now, thank you! That's a lot easier than covering it all with particle board!

 

[astroracer]

If you don't want to put a real ceiling in look into insulation support "wires". Home Depot or any lumber yard should carry them.
https://www.homedepot.com/p/THEWORK...VENvACh03BgYQEAUYASABEgI4ufD_BwE&gclsrc=aw.ds