what to do about great stuff (probably) in all the walls and ceiling...

[Oxide7]

We're taking out the walls and ceiling (not sure how to get ceiling panels out yet) and it looks like the entire bus is lined in great stuff.


It has an R-value (low, like 3.7) but it's not ideal I guess. Do I need to scrape it all out and start from scratch? Insulate over it? Leave it as is?

What are my options?

 

[o1marc]

Are you sure it is Great Stuff, or professionally installed closed cell foam?. If it is indeed Great Stuff open cell foam, I would not want it in my bus.

 

[Oxide7]

Are you sure it is Great Stuff, or professionally installed closed cell foam?. If it is indeed Great Stuff open cell foam, I would not want it in my bus.

I was wondering the same.


It was an airport bus. It could be professional stuff. I don't know how to tell though. Did you see the picture? Any idea how I would know?

 

[o1marc]

After blowing the pic up it is too uniform to be Great Stuff. I would leave it and add rigid board over it or what ever else you have planned.

 

[Oxide7]

After blowing the pic up it is too uniform to be Great Stuff. I would leave it and add rigid board over it or what ever else you have planned.

Here's a close up.

 

[ol trunt]

Just an FYI. The original Great Stuff is closed cell. How do I know?--the internet told me so. I spent hours researching this question and actually found a couple of DuPont sponsored statements to that end. Of course I don't have any idea where those "facts" are located 6 years down the river. I did, however, test the original "Home Depo" $4 a can spray foam. I sprayed a large patch of it, let it cure, cut a section out of the cured foam and pressed it under water for a week. When I released the sample it bobbed right up just like it had when I was trying to submerge it. I had marked the volume of the close fitting vessel the sample had been placed in and saw no discernible change in that volume when I released my test sample. Good enough for me. I wanted to fill the original unibody frame on my Morris Minor woody wagon Toad with the Great Stuff to keep water out (I'd built a tube frame that allowed me to place the MM on a 4x4 Geo Tracker chassis so I didn't much care about the unibody frame other than to stop it's rusting).

A quick note about Great Stuff---you have to let it boil out as it cures or it won't cure and becomes a sticky mess. In the attached pic you will see several Openings in the unibody frame, These were sealed with clear packing tape, filled with GS and then sliced open to allow for the "boiling". Once the foam cured I trimmed off the excess. Done deal.
Jack

.

 

[PNW_Steve]

After blowing the pic up it is too uniform to be Great Stuff. I would leave it and add rigid board over it or what ever else you have planned.

That is my take as well. I once had a job that involved using Great Stuff everyday. There is no way I could apply it from the can and have come out that uniform.

Looks like pro applied polyurethane foam to me. I would keep it and, if needed, add some foam board like Marc suggested.

 

[Oxide7]

This is all great info and great news. Thanks everyone.


It sure does save us a lot of effort and money. What a lucky find!

 

[brokedown-SKO]

Seems like under the window insulation is a pre-solved problem!

 

[Oxide7]

Seems like under the window insulation is a pre-solved problem!

It's actually like this everywhere on the bus. The only place that doesn't have it is above the driver side windows where all the wiring is.


The entire underside of the bus is covered in the foam too.

 

[musigenesis]

It's actually like this everywhere on the bus. The only place that doesn't have it is above the driver side windows where all the wiring is.


The entire underside of the bus is covered in the foam too.

Pics? That must be a sight.

 

[Oxide7]

Pics? That must be a sight.

It's pretty gnarly because of road grime.
I'll have to try to get some pics this weekend. It's raining right now.

 

[Artor]

As it looks like a pro job, and scraping all of that out would be problematic, you might consider Prodex over top of the foam. They claim R22 from a single centimeter of their product, with vapor and reflective barriers combined. I'm planning on using in my bus, as I can't spare losing the inches, and I don't want to have to raise my roof.

https://www.insulation4less.com/insulation4lessproduct-62-prodex-total-10m.aspx#fragment2

 

[PNW_Steve]

As it looks like a pro job, and scraping all of that out would be problematic, you might consider Prodex over top of the foam. They claim R22 from a single centimeter of their product, with vapor and reflective barriers combined. I'm planning on using in my bus, as I can't spare losing the inches, and I don't want to have to raise my roof.

https://www.insulation4less.com/insulation4lessproduct-62-prodex-total-10m.aspx#fragment2

The Insulation4less website, and the snake oil that they are peddling, come up here with some frequency.

Their claims are very misleading. The claim of R-22 in with one centimeter is pure BS.

If you could get R22 from a one centimeter at a reasonable price we would all be using in our buses and homes.

It does make a nice windshield cover when you are parked.

 

[Oxide7]

The Insulation4less website, and the snake oil that they are peddling, come up here with some frequency.

Their claims are very misleading. The claim of R-22 in with one centimeter is pure BS.

If you could get R22 from a one centimeter at a reasonable price we would all be using in our buses and homes.

It does make a nice windshield cover when you are parked.

I was about to say... That's a real tall claim to get r22 from less than an inch and no one is singing it's glory anywhere?


I think we'll just add an inch of pink xps over top and go from there.