How much insulation did you add to your bus?

[TygerCub]

Like many folks, I want to add extra insulation to the bus with the plans to make it more livable in the long-term.

I've seen a lot of builds add foam directly over the interior walls, and many more people remove the interior and fill the cavity with foam board before recovering. But how thick is the average addition? Is 2 inches in each wall enough? I would think 3 inches would be an ideal combination of R factor without sacrificing too much space.

My local big box store started carrying 2" of the pink & blue 4'x8' sheets that claim R10, but it's about $30/sheet. And another store now has the 2" white bead-board that's a R8 at $15/sheet. So for the same price I can get almost twice the insulation.

Any thoughts from those who've been there, done that?

 

[syke]

Here is what I did on our bus:

3" fiberglass batting where the windows once were.
1" white and some blue "dow" foam on the floor.
No insulation on the roof, we're thinking of going with a commercial carpet of sorts.

With that being said, I do not think my "insulation" attempts will really add much in the R value department. From the start it was more about sound deadening. Which so far I am quite pleased with.
The plan is to attack the lack of insulation by following the seasons and running a little wood burner.
We'll see what happens.

 

[SeanF-SKO]

In the walls & ceiling I have 1" of rigid foam, plus two layers of foil-faced cotton, 3/8" thick. The floor is (from outer to inner) 1/2" foam, 1/2" plywood, and finally engineered oak flooring.

My obs:
More would be better, I think. Over night, in temps above freezing, the bus will stay 10 degrees F above the outside temp without running a heating appliance. A Big Buddy propane heater on low will add another 10 degrees. Same for an electric heater on low (750 watts IIRC. Details are in another post...somewhere around here.) In summer, in the daytime, the bus stays about 10 degrees cooler than outside if I leave the windows open all night, and close everything up before it starts getting warm outside (warmer than inside). Closing curtains is important on the sunny side of the bus.

I think most of my heat loss is through the floor, and also through the front. To block off the front I have a quilt (just a king-sized bed quilt) that has been modified to fit the cross-section of the bus. It hangs from small hooks in the ceiling. Trying to insulate the front area would be really difficult -- too much glass & sheet metal, too many nooks and crannies. The best solution (from an insulation standpoint) would be a real insulated wall with a door between the living space and the driver's area. Buuuut (and there's always a but) the location of the dog house and the passenger side front wheel hump would make it tricky.

However, I also like taking down the quilt and having a bunch of daylight streaming in when the seasonal temps permit.

So, all trade-offs considered, if I were to do it again, I would just make the hanging quilt-divider thing more robust and find a way to make a good seal betwixt it & the walls...strip magnets sewn in at the edges, or snaps or Velcro? Or do partial wall with an insulated curtain for half or 1/3 the width on the right.

And maybe increase the insulation under the floor.

 

[lornaschinske]

Where? Ceiling? Wall? Floor?

 

[TygerCub]

Where? Ceiling? Wall? Floor?

The initial question was about the walls.

I want no less than an inch of insulation on the floor. I'll probably do 2 inches since (*I'm short* and) the roof is higher than normal and I may augment walkways with thick throw rugs. After living in a home with a bedroom over an uninsulated "mud room", I'm all about putting extra insulation on the floor to help keep my feet warm in the winter - socks and slippers don't always cut it .

For the ceiling, I'm debating 2 paths, both of which involve adding a full-length roof-deck:
1) Taking down the interior metal and reinsulating with 1-1/2" of board foam (made of layers of thinner material), then resurfacing like most folks do.
2) Leaving the interior alone. Gluing several layers of foam board to the roof, cover with a waterproof material (pond liner, fiberglass, whatever), then covering that with the roof deck.

Option 1 is conventional and a proven method that works.
Option 2 is totally experimental and I'm probably not brave enough to try it. But it has potential to be just as effective as #1 and provides the advantage of not lowering the ceiling in the living area if I wanted to add more insulation.

My main purpose is to get the best Rvalue possible while infringing the least on interior space. This may eventually be a long-term living space for me. I want to do it right the first time instead of wishing I'd taken the time and spent the money to do something better.

 

[AMKing-SKO]

I haven't added any extra insulation. When my family and friends go out we only go when the weather is nice.

 

[lornaschinske]

... Like this? http://www.busnut.com/artgm04.html
I'm also very interested in this approach. Even if I carpet the roof with as many solar panels as I can afford (and they will help shade the roof), I may also insulate the outside of the roof. Anything you can do to stop the heat from reaching the bus's structure in the first place should be worthwhile...

I would think that it would be a good idea if you were building a roof top deck, to insulate under the deck. Sort of a modified version of George's Super Insulated Roof.

 

[TygerCub]

Yeah! That's an awesome link, and pretty much what I was thinking of doing. Thanks.

 

[dirtygoat]

I'm using 1.5" foam board, then duct tape over all the seams... I can already tell a difference with just half of it done...