1986 TMC 102A3 - Subfloor Question

[Jim Blackwood]

It's easy to get overcomplicated with things, but the liquid vapor barrier is an easy and cost effective solution.

Here is one version:
https://www.wrmeadows.com/air-shield-lm-all-season-liquid-air-vapor-barrier/

And here is another:
https://www.youtube.com/watch?v=9N52mBnsMzQ

The poly based materials are more durable than bitumen and more effective in sealing out moisture.

Jim

[chessie4905]

We have found that tile primer is a must before installing self stick tiles. They'll stay put. Also use liquid floor wax when done to seal joints to keep moisture out. Paint joints liberally with a small paint brush. Wipe off excess perpendicular to the joints.

[jraynor]

Short of glass sheathing the plywood (which is what I've done myself, but which I realise is probably OTT) my next choice for sealing it would would be a thick layer of bitumin paint I think, simply because bitumin-coated plywood is available off-the-shelf for roofing and so it's obviously a proven solution. Bitumin paint is quite cheap too.

Also - while I don't know what the reason was for using two layers of plywood rather than a single thicker layer (which all-things-being-equal would be superior I think), you've actually given yourself an excellent opportunity to incorporate a layer of lead-substitute soundproofing material between plywood layers. Again you can buy ready-bonded sheets that are a sandwich of plywood and the lead-substitute stuff, and I think taking the effort now to do the same thing with your floor is something you'll be very pleased you did in the future



Jeremy

I've been trying to think of some type of soundproofing but have really been searching for anything. Been too busy on other parts of the bus. Do you know where to get any of it at?

Also the reason for using 2 layers is that it'll add strength since they will be laid perpendicular of each other and this combination provided me with the thickets floor for the best price. It will also provide a much smoother top floor for the first the finished flooring to lay on.

Currently I'm coating the flooring now. I've managed to get about 4 sheets done out of the 9 sheets that it took. Right now I have the 5th &6th drying over night. At this rate I will probably have them all done by wed if I stay at my rate of 2 per day complete. I had an issue today with water getting in around the windows so I had to temporarily seal a window. I'll have to do the same tomorrow for a different window. I'll be glad when I get to the point where I remove and panel over some of the windows and can finally get all of the windows sealed.

What does everyone use for reasealing the window frames to the chassis?

[Jeremy]

There are lots of specialist companies selling soundproofing materials that show up when you start Googling, but here for instance is some of the lead substitute mat available on Amazon:

https://www.amazon.co.uk/Advanced-Acoustics-Soundproofing-1-25m-thin/dp/B00BSBMFBM

Regarding laying two sheets of plywood perpendicular to each other to increase the strength - that is of course pretty pointless because each of the sheets is already made up of multiple thinner sheets laid perpendicular to each other. This is less true for some utterly horrible interior ply on the market which has a single thick (but invariably stringy, crappy, low-density) ply in the middle faced with two very thin plies on the outside - but any half-decent plywood will have an equal weight of wood fibres running in both directions, and be of equal strength in both.

What you could theoretically do to increase the overall strength would be to lay the two plywood sheets at 45 degrees to each other, but that would be horribly wasteful of wood

Jeremy

[Jim Blackwood]

I think the main goal with 2-ply is to bridge the cracks. This makes sense if a thin finish covering is being used as it reduces relative movement between the sheets, much like a conventional subfloor/hardwood combination. Helps keep edges from popping up.

Just about anything can be used to lock it all together, some choices being better than others. For instance, that 2nd link I posted could be poured and spread before laying the 2nd layer and they would then be permanently bonded. It should support gap variations of about 1/8" I would think. Or you might find something you like better.

Jim

[eagle19952]

Call me crazy, but, I would not use 3/8 ply any where for flooring.
If I did, I would use it below the thicker piece.
If my goal was 1 1/4 inch, I'd use 5/8 pressure treated plywood x's 2.

[Dave5Cs]

Crazy

[chessie4905]

I hope the 3/8 plywood is solid without any voids between layers.

[sledhead]

the 3/8" will be fine and there will be a finished floor on top of that .
but granite or ceramic tile will not work

dave

[jraynor]

My plan it to use vinyl wood look planks that lock together (not the type you can grout or place side by side). This would be great against water, its tough, and it can handle the temperature changes without buckling, and its easy to work with.

[lostagain]

Yep. Vinyl flooring is the latest and greatest.

JC

[Jim Blackwood]

OK this may be a stupid question, but what is wrong with the floor that comes in the bus? Not yours specifically, but definitely as applied to the late MCI buses like the D series.

Jim

[jraynor]

OK this may be a stupid question, but what is wrong with the floor that comes in the bus? Not yours specifically, but definitely as applied to the late MCI buses like the D series.

Jim

question is, where can you buy it? It looks just like a roll of wood look vinyl which is fine and all, but for them installing it in a bus without seats, its very easy. versus someone with walls and cabinets and such wouldn't be so easy to work with compared to single plank at a time. another thing would be at what variety can you get it? Lowes, Home depot and plenty of flooring places are now selling the vinyl planks at competitive prices and colors

[buswarrior]

Jim,

Busnuts often choose to strip the entire floor out, when they find it badly rotten down the back.

2 things do this, deteriorated sealing in the rear wheel wells let the tires introduce moisture into the floor, and the unintended introduction of water from above... many wrongly blame the toilet, but it's really the bus cleaners...

They are taking one trip into the coach with the mop... so it gets loaded up sopping wet, and down the back they go, and work their way forward. Standing puddles are left down the back, water into every nook and cranny, every day, thru its service life.

Also, ribbed flooring is a lovely hard wearing floor treatment, but it is very uncomfortable under bare feet. As the busnut tries to remove it, sometimes the plywood tears apart... project creep, what starts as a floor covering job evolves into subfloor replacement...

There's nothing wrong with a stock floor, so long as it isn't too far gone.

happy coaching!
buswarrior

edit: forgot the 102 DL wrinkle... the earlier DL's had a flex problem, they were known to tear the floor, floor covering separated, ply actually splinter...(as well as the big side panels coming away from the frame work) be sure a DL has had the strengthening modification done to it, if you get one. The 40 footers didn't have this problem. Aftermarket wheelchair installs are the wild west... some were crap, some were fine, from a structural standpoint...

OK this may be a stupid question, but what is wrong with the floor that comes in the bus? Not yours specifically, but definitely as applied to the late MCI buses like the D series.

Jim

[Jim Blackwood]

I see, and thank you. I guess the follow up question would be, what years needed the strengthening mod? I'm guessing the type of service largely determined the level of floor damage, say midwest vs mountainous.

So if possible, inspection should include bouncing on the floor over the wheelwells at the walls and along the rear bulkhead I'm guessing. Any reason why a mostly solid floor couldn't be overlaid with something else? I'm thinking that interlocking planking could be glued down for instance.

Jim