Insulation options and best practices

[arfisher83]

I have been working on insulating the inside of my bus for quite awhile now. I am going into a lot of detail on the insulation because I want my bus to be the most weathertight bus on the road. I started out by focusing on the roof. In the heat of summer your roof takes most of the heat from the sun, and in the cold weather, most of your heat loss from within the bus will also be through the roof. I bought a fibered aluminum roof coating that comes in .9 gal cans. It consists of aluminum flakes mixed in with ashphalt. I used a paintbrush to spread this over the entire outer surface on my '88 Carpenter. I put two coats on the roof with special emphasis on the seams in the sheet metal. The product dries to a silver finish, providing a roof surface that will reflect away the hot rays of the summer sun, in addition to adding a tough waterproofing layer. I spray-painted over this with a metallic-silver color to make the surface even brighter to reflect more heat. On the inside of my bus I wanted to add more insulation to the roof, but I had to take into consideration the issue of head clearance, since I am 6' and bumping my head on the roof of my bus would be quite annoying. I bought 3/8" foam board with a foil face for radiant insulation. I glued it to the metal roof, then used heat-reflective tape to cover all the seams. I then put on my pine boards over all the insulation to give it the finished look inside.
On the walls, I left the original sheet metal and insulation intact. I ripped a bunch of 1" furring strips with my tablesaw and screwed them to the inside wall of my bus, framing around all the windows and doors. Between the furring strips I placed 1" thick foam insulation. Over that I plan to put aluminum foil to provide a heat-radiant barrier. Once all the foil is in place, I will put my pine boards over it and give it the final look.
I'm a carpenter, and I've learned how important insulation really is, even in a bus, if you are looking for a comfortable living space on your trips. Don't bother tearing out the inner layer of sheet metal. It's just going to make a lot of dirty work for you. Sacrifice a few inches of interior width and put some foam insulation inside the bus. It'll make a difference. As far as insulating the floor, I haven't gotten that far yet. With more material, you're losing valuable headroom in your bus. I'm trying to come up with a way to insulate the floor beneath the bus, so as not to lose any more clearance. Hope this helps.

Adam

[dentarthurdent]

arfisher83:
have you posted photos of your insulation job anywhere? I'd love to see that.

[arfisher83]

I put a lot of attention toward insulating the interior of my '88 Carpenter. Since most heat transfers through the roof, consider it the most important place to seal up and insulate. You can take a look at what I've been doing to my bus, aka: "Buscephus."

http://www.skoolie.net/gallery2/v/Sk.../The+Bus+Pics/

It's still in the works but I've spent a lot of time on making mine weathertight.

-Adam

[timbuk]

adam what make was the roof coating you used was it the stuff for mobile homes? how many galllon cans did you use? i like the looks of it too. tim

[Train-train]

Interesting subject.

My family and I took a two week vacation during the Christmas Holidays and we experienced all kinds of weather. Many of the night temperatures were in the low twenties and a couple of them were in the teens. Our bus is a 26' '95' Thomas 5.9 diesel. We have done very little as far as any conversion to it. I like the space and really don't want to obstruct it. I have track seating in there and I can rearrange the seats in any formation I like. We just threw down mattresses. I heated it with a radiant plaque heater that has thermostat control. We did put curtains that hang over all the windows by rare earth magnets. We also put sheets hung by magnets at both ends of the bus to contain the heat.

IT all worked pretty well, much better than I had expected. What I found is that it was really easy to prep and take down every morning and night. I do not plan on camping that much in the winter time. Even so, we used only one thirty pound tank for heat over two weeks. I can not justify the time or effort to do the insulation job that many are describing above. I really think the curtains help the most and making sure they are easy to manage is of highest priority.

[Rowdymon]

Ahhh, reviving old threads...

Hope y'all don't mind too much.

I'm bringing this up because I started doing research on insulation, and I was curious about radiant heat barriers (aluminum foil basically), like we are putting into our attic.

I've found many websites that state that in order for radiant barrier to work properly, you need dead airspace between it and the roof or walls..

So my question here, especially for those who have tried it both ways, is there a noticable difference, or are we just looking to add a bunch of expensive aluminum foil to our bus skins?

[TygerCub]

I, for one, am glad this has been revisited! Don't know about radiant insulation in the roof section. Without air space, I can understand how it's effectiveness may be compromised. It's still insulation and should still help, but it probably wouldn't be as effective as it would be in it's correct application.

In my mind, two of the most efficient (if not most effective) ways of protecting the roof from heat of the summer sun are 1) add a roof rack for instant shade against the hot summer sun, and 2) if you can't build a roof rack, paint the roof with an insulating paint - i.e. one that has glass or ceramic additives that help reflect the sun's rays. Several folks here have used the paint on their bus and remark at the noticeable difference.

As for protecting the interior from heat loss during the winter... nothing beats a thermal break and good old-fashioned insulation! Wood furring strips along the bus framework with insulation in between, covered by a thin sheet of luan shouldn't take up more than 3/4 inch. But keeping the metal from radiating cold through it's rib structure could make a big difference to the interior comfort in cold weather!

[Rowdymon]

Well I have to wonder, after doing some reading...

There are two basic differences in the types of radiant barrier available for roof/attic insulation. Paint on and foil that is backed with something, be it paper, bubble wrap, what have you. The websites I have read and research all state that the foil is more effective, but require airspace to work properly, and blocks 90 something percent of radiant heat. They state if it touches the insulation it is not effective. Interestingly enough, the paint style lists as being 5-75 percent effective, depending on how it is applied, how thick, if it's watered down, and amount of aluminum material in the paint. Additionally inhaling the fumes from radiant barrier paint is apparently toxic, just from the aluminum in the paint that actually makes it radiant.

Could the direct contact be another reason why paint is less effective than foil?

Attics have air flow, or should, generally that wicks hot air up and cold (or at least less hot - especially down here in Houston), and from what I understand, is what allows the majority of the radiant barrier technology to work. Please correct me if I'm wrong with that.

Now other types of insulation, such as foam board, spray in, expanding, etc...etc... would seem, at least in my wee brain, to be worth much more, white paint or a shielding deck above even better...

[Sojakai]

Comment from Left Field... You were Warned!

I tend to think of Insulation in about the same way as sex. The more forms of protection you have, the better off you will be...

Why not put Dynamat type insulation in first, then spray foam inside. If you use wood for your inside walls you probably dont need the wood strips except for adding more insulation into the wall space... Use the Ceramic Paint additive mixed in with your light colored roof paint (radiant?, I have heard that Rhino-lining works as an exterior insulator also, plus its easy to clean) on the outside.

Not sure, are these enough?
1. Rubber backed foil
2. Spray foam
3. Wood faceboards / wood strips on ribs
4. Ceramic Additive / Rhino-Lining
5. Light colored paint
6ish. Radiant Paint Additive

[Sojakai]

I dont think I have ever had anyone quote me before. Go for it! ^.^

[jsin04]

Originally Posted by Steve

Another thing you see people doing is drilling some holes in the panels and squirting expanding foam up into the roof so that you don't have to actually remove the panels.

No experience, but I've heard the foam stuff can vibrate into dust due to driving.

[Robin97396]

If you put expanding foam into the ceiling it's going to fit tight. How is it going to vibrate and turn to dust? Anything is possible, but if the foam is vibrating and rubbing against other surfaces, someone was a little cheap on the foam application. There shouldn't be any room left for rubbing against any surfaces.
I know my foam doesn't vibrate and there's certainly been no powder coming from anywhere. As always, do what you think is safe so you don't have any regrets.

[jsin04]

Originally Posted by Robin97396

If you put expanding foam into the ceiling it's going to fit tight. How is it going to vibrate and turn to dust? Anything is possible, but if the foam is vibrating and rubbing against other surfaces, someone was a little cheap on the foam application. There shouldn't be any room left for rubbing against any surfaces.
I know my foam doesn't vibrate and there's certainly been no powder coming from anywhere. As always, do what you think is safe so you don't have any regrets.

I'm hoping that's case as I was planning on using foam for mine as well. Just saw that comment and it scared me.

[jsin04]

What do you guys do about the windows? I mean, you can insulate as much as you want but I would think those windows would negate a large portion. Are thick curtains enough? I saw someone mention using magnets to attach curtains. I like that a lot as you could put magnets in the bottom and the sides of the curtains and keep them from moving around so much thus (hopefully) making them better at keeping heat/cold in/out.

[EastCoastCB]

Spraying foam into a closed space is untested waters, and at the end of the day would be a waste as the thermal bridging of the all steel interior would minimize any insulation gains.

[Robin97396]

Originally Posted by jsin04

What do you guys do about the windows? I mean, you can insulate as much as you want but I would think those windows would negate a large portion. Are thick curtains enough? I saw someone mention using magnets to attach curtains. I like that a lot as you could put magnets in the bottom and the sides of the curtains and keep them from moving around so much thus (hopefully) making them better at keeping heat/cold in/out.

The only thing I've found really useful for the windows is using rigid insulation panels cut to fit the windows. I use panels cut to fit into each window, as there is about a 1/2" lip all around the window that the panels fit into. The exposed aluminum window frames around the window are still exposed to the interior of the bus, so I have cut additional panels that cover up to three windows at one time that cover the exposed window frames.
I have about 60% of the windows fully covered, because I do have to see out. I like this system because I can adjust the panels so I can see out whatever direction I need.
Curtains might work during the spring and fall when temps are milder, but in the winter it's like they're not even there temperature wise.
Have you ever sat near a window feeling sort of a waterfall of cold air coming from the windows? Try getting away from sitting by a cold window in a bus, for those of us that like to keep our windows in our buses. These relatively inexpensive panels make sitting by a window into no big deal. Curtains, not so much. Of course that depends on the climate where you spend your winters.
This is a good time of year to try your curtain idea, and it won't cost much to try some insulation panels for a few windows so you can feel the difference.

[jsin04]

Originally Posted by Robin97396

The only thing I've found really useful for the windows is using rigid insulation panels cut to fit the windows. I use panels cut to fit into each window, as there is about a 1/2" lip all around the window that the panels fit into. The exposed aluminum window frames around the window are still exposed to the interior of the bus, so I have cut additional panels that cover up to three windows at one time that cover the exposed window frames.
I have about 60% of the windows fully covered, because I do have to see out. I like this system because I can adjust the panels so I can see out whatever direction I need.
Curtains might work during the spring and fall when temps are milder, but in the winter it's like they're not even there temperature wise.
Have you ever sat near a window feeling sort of a waterfall of cold air coming from the windows? Try getting away from sitting by a cold window in a bus, for those of us that like to keep our windows in our buses. These relatively inexpensive panels make sitting by a window into no big deal. Curtains, not so much. Of course that depends on the climate where you spend your winters.
This is a good time of year to try your curtain idea, and it won't cost much to try some insulation panels for a few windows so you can feel the difference.

Got any pics of your window panel setup?

[Robin97396]

At present I seem to be photo challenged. with my new android device. Very possibly you could find some photos of the panels in the more recent portion of my build. Link below my name.

[CaptSquid]

Originally Posted by jsin04

Got any pics of your window panel setup?

I've got 1" panels the length of the bus. Each panel is 4'x8' and fits nicely between the chair rail and the top electrical conduit.

[Robin97396]

I had a number of sheets of rigid insulation in the bus just waiting to be used. When the weather turned cold suddenly, I also figured out that the sheets of insulation were perfectly covering the windows if they were sitting on the chair rail. I had a lot more exposed metal at that time and no insulation, so covering the wall from the chair rail to the top of the windows seemed like a really good idea at the time. Since there is no cutting necessary the panels can still be used for their original intended purpose the following spring.
Exposed glass is not good during the winter.