House Wrap Installation in a pole barn?

[jaw22w]

I am finally getting the building I have been wanting to build since before covid hit and disrupted my plans. Now that lumber prices have come down, I have contracted to have a 30x40x12 barn built. I am having the shell built, and I will finish the inside with the help of my son. I
want to white liner panel the ceiling. The walls will be OSB up to 8 feet and 4 foot white liner panel from there up to the ceiling. I want to use R-19 fiberglass roll insulation installed horizontally, with the 2' O.C horizontal girts between the poles, as opposed to being installed on the inside face. I will also install a poly film on the inside under the interior liner panels and OSB.
My question is about the use of house wrap. As quoted the building has condensation control in the roof, but not on the walls. I know that house wrap should be installed between the exterior sheeting and the girt, so needs to be done as sheeting is being installed. I have asked my contractor for an adder for installing house wrap. I thought that his price was rather exorbitant with less than $500 in materials, although the building price is reasonable and competitive in this area. (I was a construction estimator for 25 years.)
This brings me to my question. Could the house wrap be installed on the inside of the exterior sheeting girts with the wrap folded nicely around the posts? This would leave an air gap of 1-1/2" between the sheeting and the wrap.
If this won't work, I guess I will have to pay the builder's price.
Construction start is 2 months off yet.
Thanks for any insight.

 

[Augus7us]

No house wrap on mine. Only 'bubble wrap' on the roof panels. No condensation issues here and I'm in a similar climate zone.

My take is a pole barn with girts and metal panels does not need it. If you are sheathing the outside with OSB panels then metal, I would probably use house wrap on the OSB.

 

[jack stand]

Wrap it (typar or tyvek)! Not the woven cheap tarp type stuff with tiny holes punched through it.
The metal is surprisingly air leaky and air movement through your fg insulation will NOT give you the rated value.
It's pennies in the scope of the budget. On the outside of the wall girts is perfectly fine and the materials won't be $300 and neither should the extra little bit of labor.

 

[mike93lx]

Wrap it on the exterior side of the poles, under the netal/sheathing. It's the right spot for it and will help with air infiltration

 

[billconner]

I agree with Mike and Jack, to get near the value of the insulation.

 

[Augus7us]

So do you have any evidence to back up what you are saying? I have never seen a pole building with girts and sheathed in tin, have house wrap on it. I've never read anything that has recommended it in this scenario.

In fact the opposite is what I find. There are ribs in your panels to allow air to flow. And if you insulate how is this any different than soffits and ridge vents allowing air to flow on the back of the insulation in the attic?

If you are talking a stick built house, sheathed in plywood or OSB, then I would agree.

Also, OP house wrap is not a condensation barrier as you call it. That is bubble wrap type insulation with a low R value and is there to prevent inside air touching a roof panel that may be much hotter when the sun comes out and warms the roof before the inside temp can equalize. And if there is space inbetween the tin and the wrap you risk creating a micro environment which could create moisture, and that is what you're trying to prevent. Plus it will be filled full of holes by the time you install your insulation, imo.

 

[jack stand]

Wrap it on the exterior side of the poles, under the netal/sheathing. It's the right spot for it and will help with air infiltration

That's pretty difficult with little to fasten to, and being between the wood and metal provides a drainage plain that never hurts to have. A lot of folks pupu house wrap, imo because of a sloppy installation. Having framing behind the seams allows for the proper taping.

 

[jack stand]

So do you have any evidence to back up what you are saying? I have never seen a pole building with girts and sheathed in tin, have house wrap on it. I've never read anything that has recommended it in this scenario.

In fact the opposite is what I find. There are ribs in your panels to allow air to flow. And if you insulate how is this any different than soffits and ridge vents allowing air to flow on the back of the insulation in the attic?

If you are talking a stick built house, sheathed in plywood or OSB, then I would agree.

Also, OP house wrap is not a condensation barrier as you call it. That is bubble wrap type insulation with a low R value and is there to prevent inside air touching a roof panel that may be much hotter when the sun comes out and warms the roof before the inside temp can equalize. And if there is space inbetween the tin and the wrap you risk creating a micro environment which could create moisture, and that is what you're trying to prevent. Plus it will be filled full of holes by the time you install your insulation, imo.

Sure do. A buddy built a "barndominium", didn't wrap it and has terrible in wall airflow that shows up at EVERY electrical outlet and switch and to a lesser extent at some of the window & door casing.
Didn't the OP state that he was putting poly under the interior finished wall on the inside framing?
I wrapped and taped mine with the same attention and detail as you'd do on a house. No air leaks.

 

[mike93lx]

So do you have any evidence to back up what you are saying? I have never seen a pole building with girts and sheathed in tin, have house wrap on it. I've never read anything that has recommended it in this scenario.

In fact the opposite is what I find. There are ribs in your panels to allow air to flow. And if you insulate how is this any different than soffits and ridge vents allowing air to flow on the back of the insulation in the attic?

If you are talking a stick built house, sheathed in plywood or OSB, then I would agree.

Also, OP house wrap is not a condensation barrier as you call it. That is bubble wrap type insulation with a low R value and is there to prevent inside air touching a roof panel that may be much hotter when the sun comes out and warms the roof before the inside temp can equalize. And if there is space inbetween the tin and the wrap you risk creating a micro environment which could create moisture, and that is what you're trying to prevent. Plus it will be filled full of holes by the time you install your insulation, imo.

Check out rr buildings on youtube. He wraps all/most and has talked many times about how much it helps cut down on drafts

 

[THETANK]

I am finally getting the building I have been wanting to build since before covid hit and disrupted my plans. Now that lumber prices have come down, I have contracted to have a 30x40x12 barn built. I am having the shell built, and I will finish the inside with the help of my son. I
want to white liner panel the ceiling. The walls will be OSB up to 8 feet and 4 foot white liner panel from there up to the ceiling. I want to use R-19 fiberglass roll insulation installed horizontally, with the 2' O.C horizontal girts between the poles, as opposed to being installed on the inside face. I will also install a poly film on the inside under the interior liner panels and OSB.
My question is about the use of house wrap. As quoted the building has condensation control in the roof, but not on the walls. I know that house wrap should be installed between the exterior sheeting and the girt, so needs to be done as sheeting is being installed. I have asked my contractor for an adder for installing house wrap. I thought that his price was rather exorbitant with less than $500 in materials, although the building price is reasonable and competitive in this area. (I was a construction estimator for 25 years.)
This brings me to my question. Could the house wrap be installed on the inside of the exterior sheeting girts with the wrap folded nicely around the posts? This would leave an air gap of 1-1/2" between the sheeting and the wrap.
If this won't work, I guess I will have to pay the builder's price.
Construction start is 2 months off yet.
Thanks for any insight.

I just completed a pole building, I used house wrap on the walls and reflective double bubble on the roof ( which was used more for a condensation barrier). I intend to insulate in the future and I was concerned that if I used Reflective barrier insulation on the walls I would create a double vapor barrier. Wrap will allow the building to dry and not trap moisture. The wrap definitely cuts down on air infiltration. I would use wrap again if I was building another building.

 

[billconner]

So do you have any evidence to back up what you are saying? I have never seen a pole building with girts and sheathed in tin, have house wrap on it. I've never read anything that has recommended it in this scenario.

In fact the opposite is what I find. There are ribs in your panels to allow air to flow. And if you insulate how is this any different than soffits and ridge vents allowing air to flow on the back of the insulation in the attic?

If you are talking a stick built house, sheathed in plywood or OSB, then I would agree.

Also, OP house wrap is not a condensation barrier as you call it. That is bubble wrap type insulation with a low R value and is there to prevent inside air touching a roof panel that may be much hotter when the sun comes out and warms the roof before the inside temp can equalize. And if there is space inbetween the tin and the wrap you risk creating a micro environment which could create moisture, and that is what you're trying to prevent. Plus it will be filled full of holes by the time you install your insulation, imo.

Is your pole barn insulated and finished as the OP plans? I would question house wrap if it's basically an uninsulated and unconditioned space

 

[jaw22w]

Really, the question isn't whether or not to use house wrap. I have researched this question for a couple of weeks now, and I am convinced the way to go is house wrap on the outside and poly on the inside. The problem is the contractor wants almost $2K to put it on. Less than $500 in materials. For $1.5K I could put on a lot of house wrap.
There is no way I could stop the construction to put the house wrap on myself. These quick sketches show how I am proposing to install the house wrap after the siding is on.
I can't see where it would be a problem. Maybe some one can see a problem.

 

[mike93lx]

That will be a royal pain in the ***. Just let him do it.

 

[jaw22w]

That will be a royal pain in the ***. Just let him do it.

Yeah, it wouldn't be as easy as putting it up on the outside would be! But I think with 2 people it could be done in a day. And save $1500 plus. I'll work for a day for $1500. (My son is free help) I'm retired and have more time than money!
I'm really just concerned about moving that air space from inside of the house wrap to the outside of the wrap.

 

[jack stand]

Jaw I don't understand the last concern above.
What is your concern with placing the wrap on the exterior wall girts? It would simplify the installation tremendously not to mention the other benefits of a drainage plain. Not a huge concern with metal but the years of possible condensate...
Good housewrap is water proof (liquid).
On the outside of the girts, 30x40x12 is a done by lunchtime job. A good supplier will have a selection of roll widths to eliminate waste, hell I've haven't seen it but they might have a 12' roll. I regularly worked with 10' for covering 9' ceiling and band boards. Cutting a whole roll with a skilsaw to width is done all the time also if it avoids wasting material or time.
No real need to do the gables if it's unconditioned space.

 

[theupsidedown]

Sooooo....obviously it's way easier to do it with the siding off.

But.

...just hypothetically let's just hypothetically suppose that the building is already built (hypothetically). Like, say you come into position of an uninsulated bare post frame building and you'd like to finish the interior and insulate.

Is there any way to get an air barrier in place (and a water barrier for the insulation, even if not the girt/post wood) without taking all the siding off, house wrapping it, and putting all the siding back on? Even if it's not perfect, if it gets 90% of the benefits (most crucially a 100% air barrier), I'd be happy.

I've been considering something like what @jaw22w is suggesting, though I'll admit I was thinking of cutting/sealing the wrap on the side of each post. Basically install housewrap in each bay between the posts and seal around the border with some sealant under the edge and some heavy-duty acrylic tape (e.g., zip system) over the seam.

I didn't want to put housewrap all the way around the post because that would effectively create an undesirable drainage plane on the interior of the post and potentially trap moisture in a tight space between post and housewrap.

In other words, my idea is something like this modified version of @jaw22w 's diagram: bead of sealant under the wrap on the blue dots (remember this is a top-down view so it runs down the whole post), cut the wrap at the red lines, then tape over the seam on the green lines.



What do you all think? Any other solutions? Don't mean to thread-jack, but I think @jaw22w and I basically have the same concern. Apologies if I overstepped!

 

[mike93lx]

Sooooo....obviously it's way easier to do it with the siding off.

But.

...just hypothetically let's just hypothetically suppose that the building is already built (hypothetically). Like, say you come into position of an uninsulated bare post frame building and you'd like to finish the interior and insulate.

Is there any way to get an air barrier in place (and a water barrier for the insulation, even if not the girt/post wood) without taking all the siding off, house wrapping it, and putting all the siding back on? Even if it's not perfect, if it gets 90% of the benefits (most crucially a 100% air barrier), I'd be happy.

I've been considering something like what @jaw22w is suggesting, though I'll admit I was thinking of cutting/sealing the wrap on the side of each post. Basically install housewrap in each bay between the posts and seal around the border with some sealant under the edge and some heavy-duty acrylic tape (e.g., zip system) over the seam.

I didn't want to put housewrap all the way around the post because that would effectively create an undesirable drainage plane on the interior of the post and potentially trap moisture in a tight space between post and housewrap.

In other words, my idea is something like this modified version of @jaw22w 's diagram: bead of sealant under the wrap on the blue dots (remember this is a top-down view so it runs down the whole post), cut the wrap at the red lines, then tape over the seam on the green lines.



What do you all think? Any other solutions? Don't mean to thread-jack, but I think @jaw22w and I basically have the same concern. Apologies if I overstepped!

Spray foam. Air seal and insulate all at once

 

[nadogail]

What are the opinions of the Professional Architects and Engineers who are involved in this project?

 

[Smoker]

What are the opinions of the Professional Architects and Engineers who are involved in this project?

Why would an architect have anything to do with a pole barn?

 

[jaw22w]

Sooooo....obviously it's way easier to do it with the siding off.

But.

...just hypothetically let's just hypothetically suppose that the building is already built (hypothetically). Like, say you come into position of an uninsulated bare post frame building and you'd like to finish the interior and insulate.

Is there any way to get an air barrier in place (and a water barrier for the insulation, even if not the girt/post wood) without taking all the siding off, house wrapping it, and putting all the siding back on? Even if it's not perfect, if it gets 90% of the benefits (most crucially a 100% air barrier), I'd be happy.

I've been considering something like what @jaw22w is suggesting, though I'll admit I was thinking of cutting/sealing the wrap on the side of each post. Basically install housewrap in each bay between the posts and seal around the border with some sealant under the edge and some heavy-duty acrylic tape (e.g., zip system) over the seam.

I didn't want to put housewrap all the way around the post because that would effectively create an undesirable drainage plane on the interior of the post and potentially trap moisture in a tight space between post and housewrap.

In other words, my idea is something like this modified version of @jaw22w 's diagram: bead of sealant under the wrap on the blue dots (remember this is a top-down view so it runs down the whole post), cut the wrap at the red lines, then tape over the seam on the green lines.



What do you all think? Any other solutions? Don't mean to thread-jack, but I think @jaw22w and I basically have the same concern. Apologies if I overstepped!

I posted this question a little over a year ago before the project was even started. The project has progressed since then. I decided to dispense with the house wrap and have 1-1/2" to 2" closed cell foam sprayed on the walls. The foam is installed and R19 fiberglass is completed. This has made the building unbelievably tight. Even without a ceiling as yet, and the almost 100 degree temps, the building stays comfortably cool. A guy could hardly work in there during the day before the wall foam and insulation was installed.
As for house wrap, I would highly recommend its use before the siding goes on, but if you have a pole barn without house wrap installed, foam is the way to go.
30x40x12 barn. 1-1/2" to 2" on walls only was $3200. I thought that was a hell of a price.
The only downside I can see is if an exterior siding sheet gets damaged, you loose the foam when replacing the sheet. With house wrap before foam you wouldn't have that problem. The way I see that, is if the building gets damaged my insurance will be paying and they can pay for replacing the foam also.

 

[Firebrick43]

The other downside is if just one leak and the foam holds the water which rots out the wood post/girts and rust the panels.

A coworker had to rebuild the whole corner of his barn due to this. He thought it was awesome as well until 15 years later.