New schoolie

[Goodifieddude]

When I converted my bus I insulated the bottoms of the walls and over all the windows in the back half of the bus but I did not insulate the metal ceiling now I'm living in it and don't want to tear the ceiling out does anybody know of an inexpensive way that I can insulate this with something that is self adhesive or something

[LincolnEcho]

Hi and welcome!!

What type of bus do you have? If it's a bluebird the rivets are easy as pie to shear off with an air chisel. Worth all the work because of a: you get to insulate it really good before you seal it back up with the same metal. b: if you decide to use another cover like the strips of wood, you'll have some really good metal for other projects on the bus.


If they are screwed in just leave it. If you already have plenty of headroom then line it with Tyvex and the ornate cover of your choice.

[T-Bolt]

If there isn't fiberglass insulation in there you can use the large commercial cans of Great Stuff. Drill holes in a systematic pattern and with a tube on the Great Stuff spray the cavity full. You can plug the holes with white plastic rivets if your ceiling is white.

[brokedown]

There are rally only 2 options here. One is popular, and the other is good.

The popular option is to line the ceiling with Reflectix. I did it in my short bus, it makes a small difference even, probably more of a difference than upgrading the fiberglass between the ceiling and roof makes. but that's a really low bar. It's not too inexpensive and it's easy to work with, you could cover your ceiling in about half an hour. The down sides being that it's not very good insulation (it's R value rating quires a big air gap that you won't have), and now your bus looks like a space capsule and every tiny bit of light will reflect everywhere.

The less popular bit more effective option would be to line the ceiling with xps foam insulation. Half inch XPS will flex with the curves of the bus, and you can use most adhesives to secure it in place. This will provide a legit R value of 3, far greater than what reflectix would give you. THe downsides are that it will take more time to install, and unless you paint it your bus will look like a construction project that never got finished.

Don't bother trying to improve the insulation between the ceiling and roof. If you're planning to keep the metal ceiling, anything you do above it is a waste of time effort and money.

[EastCoastCB]

Originally Posted by T-Bolt

If there isn't fiberglass insulation in there you can use the large commercial cans of Great Stuff. Drill holes in a systematic pattern and with a tube on the Great Stuff spray the cavity full. You can plug the holes with white plastic rivets if your ceiling is white.

Do NOT do this, folks. This has been discussed here many times. Its a bad idea.
http://www.skoolie.net/forums/f13/gr...uff-10667.html
http://www.skoolie.net/forums/f13/gr...lls-14074.html
http://www.skoolie.net/forums/f13/gr...ibs-13813.html

[EastCoastCB]

Originally Posted by brokedown

There are rally only 2 options here. One is popular, and the other is good.

The popular option is to line the ceiling with Reflectix. I did it in my short bus, it makes a small difference even, probably more of a difference than upgrading the fiberglass between the ceiling and roof makes. but that's a really low bar. It's not too inexpensive and it's easy to work with, you could cover your ceiling in about half an hour. The down sides being that it's not very good insulation (it's R value rating quires a big air gap that you won't have), and now your bus looks like a space capsule and every tiny bit of light will reflect everywhere.

The less popular bit more effective option would be to line the ceiling with xps foam insulation. Half inch XPS will flex with the curves of the bus, and you can use most adhesives to secure it in place. This will provide a legit R value of 3, far greater than what reflectix would give you. THe downsides are that it will take more time to install, and unless you paint it your bus will look like a construction project that never got finished.

Don't bother trying to improve the insulation between the ceiling and roof. If you're planning to keep the metal ceiling, anything you do above it is a waste of time effort and money.

I've priced reflectix and IMO its MAD expensive for mylar and bubblewrap.

[brokedown]

In deed it's expensive for bubble wrap but it's cheap for placebo!

[Njsurf73]

Great stuff is open cell foam, I believe. It is not good in an area that could become wet with leaks or condensation. The other problem is it wants to expand... A lot. It could buckle or bow the ceiling or roof. The minimal expanding version is not very good either.
Closed cell foam is better for the application, but still poses the risk of buckling the roof and ceiling.
Putting that bubble wrap on the ceiling doesn't sound economical or attractive.
The foam board is not a bad idea, and you can paint it or skin it with thin luan and paint or stain that. Little more work, but probably the best option for a retrofit.

[john61ct]

Agree with that last.

Shiny stuff is 99.99% useless, waste of money & time.

Spray foam best done professionally, but first thing, before starting the rest.

[Drew Bru]

We had the same issues. We didn't want to do the work of tearing out the ceiling and insulating between the ribs and putting up a new ceiling. The we got mostly done with the interior and decided we didn't like the look of the perforated metal ceiling. There was no way to really paint it so it didn't look like crap.
Here's what we did:

• We made 4" wide x 1/2" thick spacer strips out of 5mm underlayment (luan plywood, basically). We attached these directly to the ribs with self-tapping screws (probably 10 of em in each ribs since they need to hold the ceiling panels up). They conform to the contour of the ceiling fairly well.
• Next, we pieced in 22-ish" x 1/2" xps insulation between the spacers. This also conformed to the contour of the ceiling fairly well. We used insulation tape to seal the edges where the foil insulation meets the luan spacers.
• We now had a flush surface of insulation and wood to cover with larger ceiling panels of the 5mm underlayment/luan.
• We installed the new ceiling panels by using many screws (probably 24/panel) to fasten the panel to the luan spacers.
• Finally, we added one last 4" wide strip of luan to cover the slightly imperfect joint where the ceiling panels meet.

We checked with one of those space age laser gun thermometer gadgets and it made a noticeable difference, but I don't remember the numbers. It was in the 10 deg. range I think. This was a 2 day process, not too much of a pain in the ass really. Don't have any pictures of this process, but I've got a before and after.

[T-Bolt]

When I spoke of the "great stuff commercial cans" I was referring to cans of Froth-Pak that is closed cell. Both are made by DOW. As it is approved for use on steel studs, beams and roof decking it should not have any reaction with the steel in a bus.

One thing that is often overlooked here is the return on investment and long term plans for the bus. For instance there are vast differences between college kids going on road trips and long term full timers. There are countless points in between. Sometimes doing something that isn't a "best practice" works fine for your goals.

[Tango]

The Bubble Wrap, aka; "Reflectix", really only provides a benefit when used in conjunction with some airspace. Best application would be to apply it to the insides of wall or roof sheets. It will reduce transmitted heat a fair amount when used on both with that airgap in between.


Won't ever compete with closed cell foam but it is a tiny fraction of the cost.

[Njsurf73]

Absolutely agree. My application is a 3 season camper. I am doing a small amount of insulation, and a large amount of cooling to make up for it. I only plan on using it a week or two per season (unless my wife finally gets sick of seeing it in the driveway and kicks me out lol)
So my plan is to only use some luan on the ceiling and a little bit of foam board over the windows I will be covering (bathroom, kitchen area, a few in the sleeping area and any closet/mechanical space). I will probably cover 50% of the windows.
But I follow these threads closely because I have found a couple of great and inexpensive ideas for better living while in the bus.
Maybe some day I will convert a full timer when I am retired... But that remains a dream.

Originally Posted by T-Bolt

When I spoke of the "great stuff commercial cans" I was referring to cans of Froth-Pak that is closed cell. Both are made by DOW. As it is approved for use on steel studs, beams and roof decking it should not have any reaction with the steel in a bus.

One thing that is often overlooked here is the return on investment and long term plans for the bus. For instance there are vast differences between college kids going on road trips and long term full timers. There are countless points in between. Sometimes doing something that isn't a "best practice" works fine for your goals.

[john61ct]

1/2" is hardly worth doing for those boondocking in snow. They would want to start with extra headroom.

[EastCoastCB]

Originally Posted by T-Bolt

When I spoke of the "great stuff commercial cans" I was referring to cans of Froth-Pak that is closed cell. Both are made by DOW. As it is approved for use on steel studs, beams and roof decking it should not have any reaction with the steel in a bus.

One thing that is often overlooked here is the return on investment and long term plans for the bus. For instance there are vast differences between college kids going on road trips and long term full timers. There are countless points in between. Sometimes doing something that isn't a "best practice" works fine for your goals.

It doesn't cure properly when injected into a metal cavity.

[john61ct]

And that's also where the buckling from expansion can happen.

The foam needs frequent and large enough escape paths. Probably best done using pourable two-part from above, rather than sprayed from below, that stuff is designed for curing without contact with air.

But lots of holes needed, whole roof will then need sealing up after.

Spray foam from below best applied to the open surface, in very thin layers to try for even thickness, as I said best done by professionals.

If you find a local outfit has jobs going, do all the prep and drive to their job so they just use up their leftovers on yours, can be very cheap.

[Njsurf73]

That's a solid piece of advise.

[ThePimentals]

You should go back in time. Watch my helpful video where I explain that this step is crucial. And heed to my advice.

[Hotpuppy]

As for foam:
It is going to expand. The blue "windows and doors" stuff is lower pressure... but any variety of foam will "oil can" your metalwork by expanding it. The only viable way is to apply foam and then shave it flush and cover it. Probably a giant PITA. Foam is made from isocyanates.... yes dear readers, a cyanide derivative. Safety is extremely important as isocyanate exposure can cause anaphylactic shock in some people. Once cured it's harmless plastic.... but foam components are not trivial. You need to ideally wear a SAR (supplied air respirator) but a good 3m 6100 series mask with the right filters will do for short term work. Exposures are cumulative, much like epoxies. Please treat all SPF with respect, your health is not worth taking a short cut with the material or vapors.

The EZ-Foam etc is basically the same material that can be applied by high or low pressure machine. I own a low pressure spray foam rig and used SPF on my house. I did a series of videos on YouTube about it and am happy to answer questions. I'm not here to promote myself so I'm not posting a link to them on YouTube.

Open cell will drain water, closed cell won't. Open cell is barely permeable to moisture. Closed cell is impermeable. Closed cell is used in Igloo coolers and it's hard enough that you barely dent it with your fist. Closed cell has a higher insulating value.

Closed cell is great anywhere that will never leak and trap water. When you find that location on your bus please let me know where it is.

Open Cell is good for anywhere that might leak as it will let the water drain out.

Insulation is about two things:
1) Thermal resistance
2) Stopping the infiltration of air and moisture.

Foam excels at both of these.... Fiberglass is good at the first 1 when it's new and before the mice nest in it.

I'm "re-converting" a motorcoach (think greyhound) and will be removing the poorly done XPS (white styrofoam) and replacing it with pink sheet material that is the full thickness of the space I have to insulate. That will take me from 1" to 1.5" on the sides and 2.5" on the ceiling. I expect it to make a difference. You can bond the sheets with foam safe adhesive and then cut them on a tablesaw or with woodworking tools.

If you are pricing foam, it's bought and sold in board feet..... and you need to allow for a waste factor of 30 to 100% when spraying it yourself. The waste amount varies by how you spray and where you spray it.

If I wanted to spray foam a bus I would call all the SPF applicators in my area and work out a bargain with them to use leftover foam on my bus at a place of their choosing. They always have leftover foam from jobs and would be happy to make something from it and have the job come to them. I'd also pay them to do the trimming and clean up as they have the tools for it.

I have a LilPup Mixsyn system in case you are wondering. It was about $8K and then you have to buy the foam which is about $2K per set if I remember right. A set is 2 drums.... 1 drum (55gal) of isocyanate and 1 drum of part B which is a cocktail of other stuff that reacts with Part A to form the foam. Part A is universal to all foams and Part B varies by open/closed/manufacturer.

whatever you do - don't leave it exposed as that's a fire / smoke hazard.

[randydupree]

Originally Posted by T-Bolt

If there isn't fiberglass insulation in there you can use the large commercial cans of Great Stuff. Drill holes in a systematic pattern and with a tube on the Great Stuff spray the cavity full. You can plug the holes with white plastic rivets if your ceiling is white.

Do NOT use great stuff for this.
Great stuff is open cell foam and holds water.
I used it on a nice old truck i had and the cab rusted out in 6 moths.