Floor Options - 2X2's or just Insulate and Plywood?

[dan-fox]

I ran across a YouTube vid the other day in which a guy used that 20 ton air/hydraulic HF jack to liven up an HF shop press. I cannot remember exactly but he referred to the air part on the back end as an "air pump" or "air engine" or similar, and the noise it made seemed to indicate that the air side of the device was some sort of an air motor that was an alternative source of pumping stroke power. As opposed to, pressurizing the oil directly with the input air. So, if those hydraulic jacks work upside down as a class of device, it might be worth your while to see if the air driven one does as well.

[peakbus]

Getting back to the plywood discussion, I would think it might be hard to get plywood to lay flat without attaching to some framing. Most plywood warps like a potato chip if not fastened or weighted down. Maybe construction adhesive use between the floor and foam, and then foam and plywood would suffice.

[N'om'ad]

Originally Posted by Brewerbob

The 12 ton is $30 cheaper and as you're getting 4 of them... more than enough to completely lift the bus if you were so inclined. Hell, one would lift mine fully loaded.

My exact thoughts too - 20 ton a corner?!

[N'om'ad]

Originally Posted by peakbus

Most plywood warps like a potato chip if not fastened or weighted down

Not my experience - some that has been badly stored does but yes, I'd glue everything and hold it down with buckets of water, bags of cement, whatever while the adhesive sets.

[peakbus]

Yah, BC plywood is probably better than our south of the border stuff.

[N'om'ad]

Originally Posted by peakbus

Yah, BC plywood is probably better than our south of the border stuff.

Hey, Sandpoint!.. Nice little town - I've stopped overnight there a couple of times.. Love that little 'German' pub just round the corner from the main drag..

[peakbus]

Eichardts is the place! Revelstoke is a Beauty too. Been years since we've been up that far but love the BC skiing and biking.

[N'om'ad]

Originally Posted by peakbus

Eichardts is the place! Revelstoke is a Beauty too. Been years since we've been up that far but love the BC skiing and biking.

Yup, that's it.. Awesome selection of beers.. Ya, Revy's ok! Well, if I'm ever down that way in ma girl I'll stop another night and give you a shout for a beer at Eichardts..

[peakbus]

Sounds Good Good luck with the project

[Thomas1985]

Don't waste your money of leveling systems and hydraulics. Carry a few wooden blocks to park on. You only ever need to level one or two tires to even it up.

[Brewerbob]

Originally Posted by Thomas1985

Don't waste your money of leveling systems and hydraulics. Carry a few wooden blocks to park on. You only ever need to level one or two tires to even it up.

I've got mine parked on some scrap crate plywood mostly to keep the tires off the dirt. Rear driver's side is off by about a 1/4" I think. Not enough to worry about if I was using it but more than I want before cutting the roof off.

[estelle bus]

I know the right insulation will hold the weight. I am using 1 inch polystyrene under 3/4 osb, just for my own personal comfort, I laid a 1.5 inch runner board under the osb directly under the main walking area, so the foam will never have to hold the weight. If the picture loads, you can see the runner.

[o1marc]

Originally Posted by estelle bus

I know the right insulation will hold the weight. I am using 1 inch polystyrene under 3/4 osb, just for my own personal comfort, I laid a 1.5 inch runner board under the osb directly under the main walking area, so the foam will never have to hold the weight. If the picture loads, you can see the runner.

Good solution to concern of compression issues with the foam board. I like the theory.

[N'om'ad]

Originally Posted by estelle bus

I know the right insulation will hold the weight. I am using 1 inch polystyrene under 3/4 osb, just for my own personal comfort, I laid a 1.5 inch runner board under the osb directly under the main walking area, so the foam will never have to hold the weight. If the picture loads, you can see the runner.

OSB is a very bad idea for a floor - it has very poor performance if exposed to water.. it will expand and never return to it's original thickness. If you've just done that I seriously recommend you pull it up and replace with ply regardless of cost & time invested - it will probably save you in the long run.

https://www.thespruce.com/osb-flooring-info-1821088

[N'om'ad]

Originally Posted by o1marc

Good solution to concern of compression issues with the foam board. I like the theory.

If the concern is unfounded in reality is it still a good 'solution' especially if it creates a cold bridge right where you walk?.. and 3/4" will spread any load you can place on it well within the compressive strength limit of the foam..

[o1marc]

Originally Posted by N'om'ad

If the concern is unfounded in reality is it still a good 'solution' especially if it creates a cold bridge right where you walk?.. and 3/4" will spread any load you can place on it well within the compressive strength limit of the foam..

IMHO it is not founded in reality. You do realize the compression strength of the board is over a ton per square foot. Why do we even concern our selves with compression strength of foam board?What could you possibly mount in your bus that spreads over 2000lbs/sf ?
I wasn't going to criticize his build, but there will be no OSB anywhere near my build, floors or walls.

[N'om'ad]

Originally Posted by o1marc

IMHO it is not founded in reality. You do realize the compression strength of the board is over a ton per square foot. Why do we even concern our selves with compression strength of foam board?What could you possibly mount in your bus that spreads over 2000lbs/sf ?
I wasn't going to criticize his build, but there will be no OSB anywhere near my build, floors or walls.

Yes I do, well not exactly that number but I know it's used under foundations of houses. Uniformly distributed loads are not the issue here though - point loads are and that's where the overlayment comes into play. I should have been clearer - 3/4" will spread any point load you can put on it.

I'm not intending to criticize other than constructively. None of us know everything and we all make mistakes. Better to catch one early than bear the cost and disruption of a buckled floor requiring a complete strip-out.

[estelle bus]

Originally Posted by N'om'ad

OSB is a very bad idea for a floor - it has very poor performance if exposed to water.. it will expand and never return to it's original thickness. If you've just done that I seriously recommend you pull it up and replace with ply regardless of cost & time invested - it will probably save you in the long run.

https://www.thespruce.com/osb-flooring-info-1821088

Any building material if exposed to water is a poor choice. Both osb and ply have they're ups and downs, ply delminates if exposed. 6 of one, half a dozen of the other. I appreciate your advice though.

[estelle bus]

Originally Posted by o1marc

IMHO it is not founded in reality. You do realize the compression strength of the board is over a ton per square foot. Why do we even concern our selves with compression strength of foam board?What could you possibly mount in your bus that spreads over 2000lbs/sf ?
I wasn't going to criticize his build, but there will be no OSB anywhere near my build, floors or walls.

I appreciate the not criticizing my build
, as far as thermal bridging, I don't have a huge grid of floor framing. Plus were leaving original windows, you wanna talk about a thermal bridge or lack there of. Putting in a wood stove, so I'm hoping for sufficient results, I live in a non insulated slump block house built by mediocre standards from 1974.

[N'om'ad]

Originally Posted by estelle bus

Any building material if exposed to water is a poor choice. Both osb and ply have they're ups and downs, ply delminates if exposed. 6 of one, half a dozen of the other. I appreciate your advice though.

Not exactly - XPS foam is a good choice for a water-exposed situation as it is virtually unaffected by it.

Originally Posted by estelle bus

Both osb and ply have they're ups and downs, ply delminates if exposed. 6 of one, half a dozen of the other. I appreciate your advice though.

Not exactly either - I've seen a lot of damaged OSB. Ply? not so much. It delaminates if exposed to weather - constant wet/dry cycles = not what it experiences in a bus - and it won't delaminate if it's got weight on it, nor will it expand and push up much like OSB does. One soaking with OSB and it's tear out time