Looking for thinnest flooring/subfloor option with some insulation

[ridetherails]

Hi! I have a 1988 Chevy B6000 I've lived in for 2 years and we're finally insulating it. The South Dakota winters have been really hard. Our original bus floor is 3/4" thick and we need the replacement to be the same or thinner, as my wife is already taller than the bus ceiling (just barely) and a roof raise is not in our budget yet. It would definitely be nice to have some insulation on the floor, but if we can't, we can't. Is there any really thin insulation or a good subfloor option with insulative properties?

We've lived in this bus for 2 years without doing a full conversion, and it sure has been hard. It would just be nice for my pet's water bowls to not freeze at night.

 

[ewo1]

Hi! I have a 1988 Chevy B6000 I've lived in for 2 years and we're finally insulating it. The South Dakota winters have been really hard. Our original bus floor is 3/4" thick and we need the replacement to be the same or thinner, as my wife is already taller than the bus ceiling (just barely) and a roof raise is not in our budget yet. It would definitely be nice to have some insulation on the floor, but if we can't, we can't. Is there any really thin insulation or a good subfloor option with insulative properties?

We've lived in this bus for 2 years without doing a full conversion, and it sure has been hard. It would just be nice for my pet's water bowls to not freeze at night.

If your not driving the bus at all, permanantely parked, do you have any skirting under the bus ?

 

[Jolly Roger bus 223]

some metal skirting or sand bag skirting and a forced air heater blowing under the bus with something like crawlspace louvres.

 

[ridetherails]

If your not driving the bus at all, permanantely parked, do you have any skirting under the bus ?

We're not permanently parked. We stay around the same area because I'm in college.

 

[magnakansas]

lowest cost

lay down 1" thick foam . walk directly on the foam. shoes off at the door.

william

 

[ridetherails]

We're not parked...

 

[ewo1]

If your not parked i'm guessing the bus moves frequently.
replacing the floor insulation, I don't know of any materials that would help you.

Easy fix for now... place some 1 inch foam board around the outside of the bus, creating a temporary skirting. Use foil tape to seal it all up. you can even paint it to match the bus or background. when the weather warms up, remove the skirting, store it or FB marketplace it...your choice.

Easiest way to solve your problem until next fall.

 

[turf]

my bus came spray foamed underneath from the factory.

i'd have a similar problem if i had to insulate inside the bus, but the way it is, i fit fine.

you'd have to clean the undercarriage pretty good, but i've seen it done to other buses as well.

i probably have an 1.5" of foam thats been under my bus since 93. a lot of miles and that stuff is darn near indestructible. dont believe someone that says it wont last.

good luck

 

[Timeline]

lay down 1" thick foam . walk directly on the foam. shoes off at the door.

william

Yes the foam is warm on bare feet, maybe a thin layer of cork flooring on top of the foam for a better look...

 

[Beeb2]

Chuck Cassady (YouTube) just put down some of that pink foam board, no framing or anything. He has a whole video (maybe a few now) about why he does it and how well it works. Probably what I would do if I did it again.

Also, I would put a big conduit under the floor somewhere, running left-to-right across the bus so I can run wires to the opposite side easier for any future upgrades/renovations. I have the darndest time trying to get wires to the other side of my bus now, and really wish I had some conduit there to make it easier.

 

[Dragonpop]

Insulation

You might look into Air Skirts. The old Bluebird Wanderlodge had the underside spray foamed so it is very durable.

 

[Rock-N-Ruth]

When putting insulation on top of the floor is not really viable, the obvious answer is put insulation under the floor. It can be some work, and currently pink insulation foam board is expensive, but it will give you the desired effect without making your inside space smaller.
At the current price of 2 in XPS foam, a spray foam kit may actually be more affordable.

 

[nikitis]

Chuck Cassady (YouTube) just put down some of that pink foam board, no framing or anything. He has a whole video (maybe a few now) about why he does it and how well it works. Probably what I would do if I did it again.

Also, I would put a big conduit under the floor somewhere, running left-to-right across the bus so I can run wires to the opposite side easier for any future upgrades/renovations. I have the darndest time trying to get wires to the other side of my bus now, and really wish I had some conduit there to make it easier.

Thanks for this idea, I'm at this stage with flooring, and didn't even consider putting a hot/cold water pipe, and electrical conduit, maybe one in the front and one in the back for easier upgrades down the road.

 

[LargeMarge-TC]

2003, we built our ExpeditionVehicle with 1" pink-board laid on the box floor.
Atop that, we laid half-inch plywood, painted on all surfaces to seal.
.
Our visible floor is bamboo around the perimeter, slate in the center.
.
We heat using a Wave 3 catalytic heater.
Sitting on the slate on its stubby legs, it warms the slate, then that radiates throughout the interior.
Over two decades full-time live-aboard, zero issues with the pink-board crumbling or otherwise deteriorating.
.
Our introduction with plenty of portraits, plus our reasons for our decisions:
https://vanlivingforum.com/threads/expeditionvehicle-build.44908/#post-576110

 

[Red_Fir]

"When putting insulation on top of the floor is not really viable, the obvious answer is put insulation under the floor. It can be some work, and currently pink insulation foam board is expensive, but it will give you the desired effect without making your inside space smaller."

How far from your exhaust do you need to maintain to keep your foam viable?

 

[nikitis]

If there is room under the bus that is the best solution. The target R Value you want to reach is 20. The best materials man can purchase to reach that is the XPS boards, and you need 4 inches of that. Spray Foam is also fine but you cannot walk on that, but you could maybe foam under the bus, and then put a protective paint on the foam itself.



Most people can get by with R15 value unless you live in extreme climates.


Ideal is 20, but even for extreme climates 20 can be underwhelming. You definitely don't want any less than R15 or you won't really feel much of a difference, These levels are needed to keep the temperature in the bus from an AC or heater. Otherwise it leaves easily and requires longer cooling or heating runs which also in turn means more electricity wasted on the AC/Heater which is one of the largest electricity used items.



The unfortunate reality is you're gonna need 4 inches of XPS to reach R20, that hard limit is a materials limitation. This is why people opt for roof raises all the time because they once they put 3 inches on the ceiling, and 4 on the floor it's now 7 inches smaller.