new project - insulation, basement questions

[olives]

Hi all!

I’m new here – have been reading for a while but now I’m posting a question.

We have not bought a bus yet, and this question relates in part to which sort of bus to get.

We live in the Northeastern U.S., so we need to take insulation seriously. I had the idea to build a box under the bus as the “basement” and then insulate around it – as in, the insulation would be continuous down the bus walls and the walls of the basement box, and then go under the basement box. The bus floor itself (above the box) would not be insulated. This way, the bus living space and the basement for storage would be one conditioned space, and we could store things in the basement without needing separate heating elements. (We want to use one pellet-burning device to heat the whole thing and avoid separate coils and electricity-drawing devices.)

The thought was that the basement wouldn’t be just for tanks, but also for regular storage, and that we could access it through trapdoors in the floor (between those metal rib things), rather than from outside the bus. I figured outside access would compromise the insulation.

I imagine that the metal floor ribs might conduct heat out of the space, so we might need to insulate around each of those. (?)

**Your thoughts on this whole idea?
**How wide and how far apart are those ribs? Thoughts on accessing the basement through trap doors between them? (versus from outside the bus)
**Know anyone who has done something like this? (Or considered it and decided not to?)

It seems that this plan would work best for a rear-engine bus, where perhaps the whole bottom could be insulated into the space together. It seems like a front-engine (dog-nose) bus, with the drive-train going down the middle, would need to be done in two sides, with the insulation going around the box on each side and then coming up and reaching floor level in the middle to keep the drive-train out of the insulated space, which would be more hassle and reduce the available storage space.

We figure we’d need to keep the drive-train out of the insulated space because if I understand correctly other things go down that line too (e.g. exhaust from engine?) and we don’t want those going into the bus if there is a small leak or such. Also, if any work was needed on the drive-train or other things in there, we want someone to be able to work on it from the outside as normal rather than through trapdoors in our floor.

**Would the baesment box-insulation work on a front-engine bus at all? Thoughts on the relative available space and hassle doing this for a rear vs. front engine bus?

**Also, how much length do I get out of a basement box? Are there other things to worry about (e.g. gas tank that we would need to build and insulate around)?

**Separately: We are planning to remove the side and ceiling panels and insulation and put in new insulation. Does removing ceiling panels compromise the bus’s stability? Advice on that?
** Does anyone replace/add insulation in the cab / driver area, or just leave that part as is?

Would appreciate getting your thoughts and advice on any of this! Thank you!!

(And feel free to post pictures of your bus underside to help explain points if that seems relevant. Thank you!)

[Twigg]

Welcome to the forum.

In truth, I think you are over-thinking this

Unless done at the factory, before the body is attached to the frame, there really is no easy way to insulate effectively under the bus. With a front engine you have limited areas you can add storage, and it has to be done separately on each side. With a rear-engine you can buy one with pass-through storage bays already fitted.

One problem you would have to overcome is that the floor ribs are bolted directly to the frame rails, and they would act as thermal bridges whatever insulation you fitted.

And it is so easy to completely cover the floor with foam board for unbroken insulation, front to back and the full width, that it is hard to justify any other method. People do ask about it, mainly to preserve ceiling height but honestly, a roof-raise is easier.

If you do get one with storage bays, or add them yourselves, only heat-sensitive items need care ... any exposed plumbing and your grey water tank. That can be dealt with by a heat mat underneath it.

[Jdawgsfanasty]

Originally Posted by olives

Hi all!

I’m new here – have been reading for a while but now I’m posting a question.

We have not bought a bus yet, and this question relates in part to which sort of bus to get.

We live in the Northeastern U.S., so we need to take insulation seriously. I had the idea to build a box under the bus as the “basement” and then insulate around it – as in, the insulation would be continuous down the bus walls and the walls of the basement box, and then go under the basement box. The bus floor itself (above the box) would not be insulated. This way, the bus living space and the basement for storage would be one conditioned space, and we could store things in the basement without needing separate heating elements. (We want to use one pellet-burning device to heat the whole thing and avoid separate coils and electricity-drawing devices.)

The thought was that the basement wouldn’t be just for tanks, but also for regular storage, and that we could access it through trapdoors in the floor (between those metal rib things), rather than from outside the bus. I figured outside access would compromise the insulation.

I imagine that the metal floor ribs might conduct heat out of the space, so we might need to insulate around each of those. (?)

**Your thoughts on this whole idea?
**How wide and how far apart are those ribs? Thoughts on accessing the basement through trap doors between them? (versus from outside the bus)
**Know anyone who has done something like this? (Or considered it and decided not to?)

It seems that this plan would work best for a rear-engine bus, where perhaps the whole bottom could be insulated into the space together. It seems like a front-engine (dog-nose) bus, with the drive-train going down the middle, would need to be done in two sides, with the insulation going around the box on each side and then coming up and reaching floor level in the middle to keep the drive-train out of the insulated space, which would be more hassle and reduce the available storage space.

We figure we’d need to keep the drive-train out of the insulated space because if I understand correctly other things go down that line too (e.g. exhaust from engine?) and we don’t want those going into the bus if there is a small leak or such. Also, if any work was needed on the drive-train or other things in there, we want someone to be able to work on it from the outside as normal rather than through trapdoors in our floor.

**Would the baesment box-insulation work on a front-engine bus at all? Thoughts on the relative available space and hassle doing this for a rear vs. front engine bus?

**Also, how much length do I get out of a basement box? Are there other things to worry about (e.g. gas tank that we would need to build and insulate around)?

**Separately: We are planning to remove the side and ceiling panels and insulation and put in new insulation. Does removing ceiling panels compromise the bus’s stability? Advice on that?
** Does anyone replace/add insulation in the cab / driver area, or just leave that part as is?

Would appreciate getting your thoughts and advice on any of this! Thank you!!

(And feel free to post pictures of your bus underside to help explain points if that seems relevant. Thank you!)

Thomas bus has a "how's it built" video that answered a lot of my questions...maybe helpful?

Sent from my VS500PP using Tapatalk

[olives]

Jdawgsfanasty - thanks! I'll look for that.

Twigg - thanks for the advice! More questions (for Twigg or anyone else): What are floor ribs and how are they spaced?

The trouble with a heat mat is if I understand they involve coils going through and draw charge. We're trying to minimize electricity draw and electrical coils in/under/by our living space due to sensitivities. Hence we'd like to include it with our existing conditioned space in the bus...

[Twigg]

Originally Posted by olives

Jdawgsfanasty - thanks! I'll look for that.

Twigg - thanks for the advice! More questions (for Twigg or anyone else): What are floor ribs and how are they spaced?

The trouble with a heat mat is if I understand they involve coils going through and draw charge. We're trying to minimize electricity draw and electrical coils in/under/by our living space due to sensitivities. Hence we'd like to include it with our existing conditioned space in the bus...

The body of my bus has 14 sections and it's 40 foot. I believe the spacing on the floor ribs is the same as the side ribs .... lemme go measure ...

They are 29" on center. Yours may be different

My guess is that to survive a Wisconsin winter you will also need a pretty substantial electrical installation too, but you may have different thoughts.

[Jdawgsfanasty]

Originally Posted by Twigg

The body of my bus has 14 sections and it's 40 foot. I believe the spacing on the floor ribs is the same as the side ribs .... lemme go measure ...

They are 29" on center. Yours may be different

My guess is that to survive a Wisconsin winter you will also need a pretty substantial electrical installation too, but you may have different thoughts.

The ribs are formed by making something similar to c-channel...you'll understand if you find the video...really crazy simple how the bus body is assembled

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[Jdawgsfanasty]

Originally Posted by Jdawgsfanasty

The ribs are formed by making something similar to c-channel...you'll understand if you find the video...really crazy simple how the bus body is assembled

Sent from my VS500PP using Tapatalk

Btw...I would underpin the bus(stationary, of course) and use some kind of small portable forced air heater directed in to the crawl space...remember you only need 33 to 35 degrees to avoid freeze up...

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[Frogpondfoug]

Steel is a fantastic conductor will always have that against us.

I live in northern Canada, i have insulated the inside 3inch spray foam, floors rubber membrane, 1/2 plywood, 2/12 sheet insulation. 3/4 sub floor. I intend on insulation the undercarriage in a small hanging box just like your have suggested. My water is under the bed, the grey water is in a heavy insulated box under us with a heat exchanger in place. Insulated removable skirting is in the works as well. With all preparation, there's only one way to find out.