[Archived]

If you are referring to the spray foam beneath the bay floors and in the wheel wells I suspect its primary purposes are sound deadening and insulation.

I would use automotive undercoating that comes in a spray can from NAPA, and not worry about the foam. If you really want it however you likely can use foam boards cut to size and bonded to the floor and maybe use the spray cans of insulating foam to fill the voids between the new and old.

[Archived]

If I don’t use something, the raw wood is exposed as well as the metal structure it sits on so being able to fully seal the underside if important. An undercoating spray could work. Thanks for that thought. I have been thinking that maybe I could use a board (plywood?) to span the gap and use the canned foam a section at a time until I fill the whole space. It’s about 2-3 inches deep in foam and would like to fill the entire space to keep things from rusting.

[Archived]

Lowes has two inch thick foam insulation 4 x 8 sheets that could be shape cut with a battery operated foam wire cutter. Then spray the auto undercoating over it. Built one with lantern battery and guitar string. Works great. Hobby Lobby sales them too.

[Dick]

This is the real deal:

Froth-Pak 210

[Art]

Will this stuff send mice, voles, chipmunks, and squirrels running away from our coaches?

[Archived]

When I replaced the floor in my water bay, I used the expanding spray foam from Lowes to fill gaps, repair holes and missing chunks. Used a corrugated cardboard box material as a form. I may have put some plastic wrap between the cardboard and foam to make clean-up a little easier.

Use a rasp or hacksaw blade to level any low spots and spray paint it black. Can’t tell the difference and still in place 3 years latter.

[Archived]

There is some waterproof spray foam available from several different manufacturers. Google will get you there.

[Archived]

Many choices for rattle can foam. After it sets for a day spray cheep flat black from rattle can over the entire area.

After a bus run in a rain storm color match will be perfect.

AL

[Art]

The canned foam seems to be working out pretty well. However, you can’t do too large an area at a time as there are 2 channels divided by the steel tubing and it leaves gap if you do too much. Had to go back and tear some out at start again but another day or so and I should have it all sealed up. I guess I am getting about 1 foot at a time, let it dry about 8 hours and I can use a piece of wire to cut the foam off the board I am using as a bottom form. It’s a little too thick which really can’t hurt anything but I may cut it down a bit before painting it black (as if anyone would look)?

I like the spray foam shown from Lowes but we are in a campground sitting on concrete and I really didn’t want to mess up the site. I suppose a sheet laid out under there would have fixed that but there’s not much room to maneuver underneath.

Nice to have a good solid floor again. It’s been pretty soft for a very long time.

[Bill]

So, if anyone else has to do this in the future, DON’T do the rattle can foam! What a PIA. I have been working on this, section by section, for a week or so and it’s still not “perfect” like it could have been if I had just taken the other course mentioned above and bought the Lowe’s 2 part spray foam. Not cheap (the rally cry of any Prevost owner) but it would have been done in a day and it would be fully sealed front to back and side to side.

It’s hard to believe that I could have made more mess than I did with the rattle cans (many) and the ongoing cleanup has been a real (OK, you know) PIA!

I know that I need to replace another 1/2 floor in the wet bay sometime in the near future and when I do I will get the right stuff from Lowe’s so I can seal that floor as well as take care of any other gaps or divits that might exist under my coach.

Just a warning that what seems to make sense is not always the best course of action.