Why are some of you insulating your bus?

[crazycal]

I see pictures of insulation being removed and new insulation being put back in. Is there something wrong with what's there?

[Demonknight]

the stuff thats there isn't ment to hold up to long term use (think house)..so we pull out the wussy stuff thats there and install better stuff.

[crazycal]

Pablo, I know what insulation is for. I was asking why people were replacing what they had. I didn't think that what's there wouldn't hold up. It gets hot where I live, but I have not been inside of the bus during that heat.

[Elliot Naess]

Cal, all that replacing of insulation is a matter of getting the most R-value into the narrow
available space. High tech plastic foam can have as much as R-7 "insulating power"
per inch of thickness (polyicycene or some such, I think -- "poly-iso"?). The little bit of
fiberglass that is in there from the factory isn't anything near that good -- maybe R-3, but
the space may not even be full of that -- and it may be soaking wet. Sure, it would
be easier to just add a few inches of the new stuff, but the bus is only eight feet wide
and space is at a premium. Same with low headroom.

Radiant barriers (aluminum foil, reflecting the heat) and other tricks also come into play
-- I'm still learning myself. Lots of folks swear by ceramic additives in the roof paint. And white!

[And I love the idea of adding three inches of insulation to each side of the OUTSIDE of
the bus, since we are allowed 8' 6" wide on the road.]

[BusNut]

Think of it this way. Buses are generally built to be comfotable in motion and with many passengers. The minimal insulation works in that situation because in the summer there is good air flow or engine driven AC. In the winter there is the heat provided by the engine plus the body heat of many in a confined space.

A motorhome needs to be comfotable while still, without the engine running and with only a few people in it, or even just one person. So a lot more insulation value is needed.

[the_experience03]

Don't forget about quieting the bugger down. I never insulated my walls, but I sure did tighten an awful lot of screws that had loosened up over the years to quiet it down. I have to wonder how many times I'm going to be doing that in the future. Taking off the original steel panels on the inside would have given me a chance to insulate, put a nicer looking finish on, break the thermal path (no steel to steel contact), and let me fasten things in such a way that it wouldn't rattle. I love Liquid Nails....

[eggman]

Removing the windows, definately makes it quieter.

[crazycal]

I was at Home Depot and looked at their insulation. The 1" pink stuff was only R3.8 maybe R4. Is there something with a better R-value?

[the_experience03]

Fiberglass, but in terms of rigid insulation nothing comes to mind.

[Les Lampman]

Originally Posted by crazycal

I see pictures of insulation being removed and new insulation being put back in. Is there something wrong with what's there?

Yes and no; it really depends on what you're trying to achieve as the end result for your conversion. Just on this site alone it ranges from comfortable tailgater/weekend/camping buses to full-fledged live-aboard conversions. How much time, money and effort you'll put into the conversion and its final use will dictate a lot of what you feel like you should do or must do (depending entirely on your own personal predilections). Really, none of us here can answer the question; all we can do is tell you what we're doing and our thoughts.

The end result of my conversion is to be a full time live aboard for a couple and I want it as nice as any professional conversion or amongst the best of the owner conversions (which are even better). As such I felt I needed to get to the outermost layer of bus everywhere I could to assess its condition; I'm going to put a lot of time and a substantial amount of money into the conversion and I want to know the bus body is in primo condition. Thus I removed the ceiling panels and am working on the side panels and I'll remove all the current fiberglass batt insulation. I'm also removing the rubber floor material as well (2/3 of it is up now) for the same reasons (I also found out it weighs a lot!).

All the interior panels that I'm removing are metal and they were (are) fastened to metal bus frames to which the outside metal sides and roof are attached. A perfect conduit for heat and cold to enter and/or leave the bus. So another goal in gutting the interior was to reinstall non-metallic interior panels so that a thermal break is created.

Energy products have come a long way in the past few years and since my bus is intended to be lived in 24/7 all year long and in whatever part of the country we're parked or traveling through I decided to find and use the products that will let me put the most insulation in the space available. I"m only go to do this once (so I say! ), I want the bus to last another 20 years plus, and I want it to be very self-sufficient and comfortable (a real home, not just a camper).

By comparison our first bus was just a camper/huge station wagon. I didn't remove any of the interior panels and had I continued with the conversion on that bus I think I'd have just lined the inside ceiling and sides with paintable cork to get the thermal break.

SeanF from the site here (he and his wife are full-timing in their conversion) has a nice web site at http://www.seanf.smugmug.com where he discusses their choice of insulation; they were going for the max.

[SeanF]

One reason is to add a foil-faced layer of insulation with the foil facing the *outside*, just under the external steel bus skin.

We just had our hottest day so far -- 97 degrees outside in southernmost Arizona. The sun altitude was around 57 degrees @ solar noon....and our bus was only 2 degrees warmer than the outside air temp. Not bad for what is essentially a steel tube with no A/C or evaporative cooling.

There are other factors...white paint, east-west bus orientation, and having every door & window open for max air flow. Our two doors are on the north (shaded) side of the bus, so the coolest available air is moving through the bus.

Hope this helps
Sean

[Elliot Naess]

Is there something with a better R-value?

Try researching polyisocy... polyisocyan... oh heck... take a look here:
http://www.daviddarling.info/encyclo...cyanurate.html