Spray foam quotes…which one would you guys pick?

[Shoester]

Getting the 20x20 “bump out” in the back corner of my shop spray foamed, and these are the option pricing the contractor gave me. Which one would you guys choose?


5” open walls, 3” closed ceiling - $3,000
5” open walls, 7” open ceiling - $2,400
5” open walls, 5” open ceiling - $2,150

3” closed walls + 3” closed ceiling - $4,100
2” closed walls + 3” closed ceiling - $3,500


Thanks for any input!

 

[PCustoms]

The 1st, but why didn't he quote closed in the walls?

 

[theoldwizard1]

How thick ? You want the MAXIMUM you can fit in the ceiling.

OR

Get 2" all around and add fiberglass roll/batts.

 

[Shoester]

The 1st, but why didn't he quote closed in the walls?

Edit: he gave me a number for that, I just didn’t read far enough.

3” closed walls + 3” closed ceiling - $4,100
2” closed walls + 3” closed ceiling - $3,500

 

[PCustoms]

3” closed walls + 3” closed ceiling - $4,100

Probably this one, but I would double check the r-value of the system he is using.

IIRC that's only ~R22

 

[NUTTSGT]

Personally, I wouldn't spray it on plastic or house wrap.

 

[1/4atatime]

Personally, I wouldn't spray it on plastic or house wrap.

I was gonna say is no one going to point that out. Op will have to rip all that out first.

 

[PCustoms]

I was gonna say is no one going to point that out. Op will have to rip all that out first.

I thought it was recommended to have a plastic "slip" layer so that metal siding be removed later?

 

[1/4atatime]

I thought it was recommended to have a plastic "slip" layer so that metal siding be removed later?

Yes and no it's ok if your using open cell to help with a vapor barrier but only on the sides. The roof never should have a barrier for spray foam. It will sag and mess up eventually. The reality is the best thing to do when it comes to condensation and foam insulation is to used closed cell direct to the walls and panels. Too many variables trying to use two barriers. This video explains it pretty well. If you have to replace a panel then you just have to rip it out and **** it up. Your going to have to respray and wrap that area anyway because a messed up panel has probably messed up the plastic.

Edit: looking at OPs pictures they have a barrier on the ceiling and the side barriers are way too baggy for my taste to spray over them.

 

[PCustoms]

Too many variables trying to use two barriers.

Yep. I just had a thread about foam and barriers.

Typically anytime I post in a foam thread I'm referring to closed cell. I've really never been convinced open cell is beneficial in any way, and it certainly hasn't made any sense on projects I've worked on.

 

[Mike65]

We had either 2" or 3" closed cell foam on the walls & ceiling done in our 24'x25' garage 3 years ago.

 

[NUTTSGT]

Yes and no it's ok if your using open cell to help with a vapor barrier but only on the sides. The roof never should have a barrier for spray foam. It will sag and mess up eventually. The reality is the best thing to do when it comes to condensation and foam insulation is to used closed cell direct to the walls and panels. Too many variables trying to use two barriers. This video explains it pretty well. If you have to replace a panel then you just have to rip it out and **** it up. Your going to have to respray and wrap that area anyway because a messed up panel has probably messed up the plastic.

Edit: looking at OPs pictures they have a barrier on the ceiling and the side barriers are way too baggy for my taste to spray over them.

Good video and I have watched a couple of his videos before. That linked video, I do see and issue with it that most will probably not pick up. All the video used, is not the same building. Some of it is stick framed and some post framed/post framed with stick built in between.

Depending on how it's built would clue me in to the choice of use. I'll agree, the OP's is way to baggy for me think about spray foam.

In the video, the stick frame with the girts and house wrap, I'd be fine spray foaming. As the foam is sticking to the wood as well as the wrap, my thought is this makes a huge difference.

Merely putting house wrap on a typical post frame with and 2x8 area of unsupported house wrap would be a no go for me. If it was my build, my thought would be to use 1.5" foam between the girts before the metal goes on. Then if you choose to spray foam, your foam is sprayed to the back side of of said foam sheets. This gives a nice solid base for the foam and fills in the area between the post and metal siding. This has been known to cause a cold spot, sweat and mold issue....as seen in MR Post Frame (youtube) in his own barndo.