Preventing squeaky floor while off-roading?

[mrsa111]

So I've just finished the subfloor in my van. It's a furring strip frame using 1 1/2" x 3/4 strips. With foam board insulation inbeteeen the strips and neoprene to fill in the little dips in the van floor and any other gaps. And thin plywood glued to the top of that. Haven't bolted it all down yet so ya just floating.

In most areas it's maybe 1/4inch off the van wall. But there are a couple tiny spots where it's touching the wall or very close, which I plan on cutting back.

I was just driving today, and took a corner with a dip, the kind that would make the van want to twist. And I heard a really loud creak/squeek that I'm guessing was from the floor. I plan to do a lot of off-roading, so I don't want non stop squeeking going on. And I don't want to damage the floor.

I'm doing 1/2"tongue and groove for the final top of the floor. Which I plan on spacing 1/4" from the wall

I'm guessing what I heard was from where it's still touching the wall. But with how easily it squeeked and how loud it was it kinda freaked me out and made me think it's gonna be a major concern for the rest of the build.

I was thinking I'd fill the gap between the floor and the wall with neoprene, and maybe even use rubber washers between the van floor and subfloor where it bolts down.

Any other tips? Or thoughts on how to avoid squeaks with he rest of the build which will have a kitchen, cabinets, bench, etc..

 

[_hein_]

Or thoughts on how to avoid squeaks with he rest of the build which will have a kitchen, cabinets, bench, etc..

I can't really visualize your floor layup so a photo would help. If you glued the strips and/or rigid foam to the plywood then that might be coming loose and squeaking due to the twist. Or it's your floor against the metal. It is the nature of a sandwich structure to generate large shear forces between dissimilar layers as the panel is bent or twisted. Many adhesives wont hold up to that over thousands of on- and off-road miles. Better to allow for motion between layers and to make sure they don't squeak when slipping across one another.

Generally speaking, you need a soft layer between the hard layers. Wood against wood, metal or a rigid foam is very prone to squeaks. We have had great results using minicell foam under plywood floors and Thinsulate in the walls and ceiling. We avoid rigid foams all together.

-Hein
DIYvan.com

 

[mrsa111]

 

[mrsa111]

So underneath the furring strip frame is neoprene in the dips of the van floor. The neoprene sticks up above the metal a tad, and there is a lot of sound deadening glued to the metal floor as well, so peobably pretty minimal metal on wood. That foam insulation is 1/2" the furring strips are 3/4" the idea being that it's not sandwiched between layers. I taped it from the bottom and tried to get as much caulk as I could between the wood and foam board to avoid foam on wood.

That plywood top right now is just glued to that furing strip frame.

And I was going to drill maybe 8 holes through the bottom of the van, to bolt the floor down. I'd use threaded inserts that ill drill into the plywood/furring strips.

I think the squeek I heard is from the wood touching the walls. So I'll definitely make sure I have a gap there. Then fill that gap with neoprene.
That really only leaves the plywood subfloor glued to the furring strips where there's much wood/wood contact. I have a thin foam underpayment I'm planning on laying between the plywood and the tongue and groove floor

 

[wjeeper]

I had quite a few squeaks when I first did the floor in my van. The foam seemed to be the biggest source of noise. I ended up taking some 3/8 ply drilling and riveting and gluing strait to the floor. No more squeaks after that.

How thick is the ply on your floor?

 

[mrsa111]

It's pretty thin, this stuff https://m.lowes.com/pd/RevolutionPly-5mm-Poplar-Plywood-Application-as-4-x-8/50121135

I was told it's sturdy compared to other stuff that thin. It flexes a tad walking on it, was banking the tongue and groove flooring elmininating the flex.

I'm hoping that because the foam board isn't sandwiched between the layers and has some free space it won't squeek. Because it'd be a pain to get he floor back out and replace it.

 

[southpier]

the frequency of fasteners and thickness of adhesive between the furring and plywood may determine how much noise the floor generates long term. everything you construct in the van will go through a stress relief process. so what squeaks today may not squeak tomorrow and (unfortunately) vice-versa. think hard about tongue & groove flooring and all the inherent seams. how are you fastening it? by your own admission, there's dynamic forces at play which don't exist in a household application of the same material. I believe the fewer joints the better. if the foam is squeaking, those squeaks may work themselves out as the foam crumbles and dents at the point of contact.

maybe against others' experience, but I am reluctant to drill through a vehicle unnecessarily. anchor to what the manufacturer provided in the way of holes or slots in the ribs (walls & ceiling). consider well nuts, vhb tape, anything which will allow you attachment without drilling. isolate anything bolted to metal - again vhb tape is your friend. dynamat or similar self-adhesive sound deadening is helpful too.

understand each piece or attachment is not a stand alone component, but rather a piece of a puzzle. each one helps the one before and after it. like a journey - one step at a time.

oops! - time to feed the unicorns on the front lawn and watch the rainbows. good luck - report back.

 

[mrsa111]

the frequency of fasteners and thickness of adhesive between the furring and plywood may determine how much noise the floor generates long term. everything you construct in the van will go through a stress relief process. so what squeaks today may not squeak tomorrow and (unfortunately) vice-versa. think hard about tongue & groove flooring and all the inherent seams. how are you fastening it? by your own admission, there's dynamic forces at play which don't exist in a household application of the same material. I believe the fewer joints the better. if the foam is squeaking, those squeaks may work themselves out as the foam crumbles and dents at the point of contact.

maybe against others' experience, but I am reluctant to drill through a vehicle unnecessarily. anchor to what the manufacturer provided in the way of holes or slots in the ribs (walls & ceiling). consider well nuts, vhb tape, anything which will allow you attachment without drilling. isolate anything bolted to metal - again vhb tape is your friend. dynamat or similar self-adhesive sound deadening is helpful too.

understand each piece or attachment is not a stand alone component, but rather a piece of a puzzle. each one helps the one before and after it. like a journey - one step at a time.

oops! - time to feed the unicorns on the front lawn and watch the rainbows. good luck - report back.

I've thought about just doing a floating floor, either with tape or some kind of adhesive, or a good rubber weather stripping or similar around the outside edge of the floor to hold it secure against the van walls.

Whats keeping me from going that route is attaching the counter, bench and cabinets, and doing it in a way thats secure when off-roading. I have plenty of pre existing holes on the walls that i can use to attach everything, but i'm not sure how i'd go about attaching everything to the floor, just let them rest on it? or still screw everything into the floor? I would think that if you had everything (the cabinets, bench, counter, floor etc..) all screwed into the floor, but the floors floating, that would encourage more movement, and more squeeks no?

 

[mrsa111]

I also went into the lumber store today to look at other options for flooring, they had this 1/2" click in bamboo flooring that looked really nice, and seemed super sturdy. The guy I talked to said you can use this tongue and groove glue/sealer in all the grooves and that should eliminate squeeks. then he said gluing that to the plywood floor should be enough and allow for a tiny bit of flex. though I think I'd at least screw it down on the edges.

Then I could use all the tongue and groove blue stain pine that i originally bought for the flooring, for the cabinets and everything instead. I have 60 sq ft. worth so it would probably be enough for everything. It looks awesome and i spent a little to much on it so I really want to use as much of it as I can!

 

[Bbasso]

I did a floating floor of three-quarter inch plywood carpet directly on top and cabinets built on to it. I don't notice any squeaks rattles or noise coming from anything I did.

 

[southpier]

...pre existing holes on the walls that i can use to attach everything ... good thing

...how i'd go about attaching everything to the floor... imagination; think of the specific part you are attaching and how it is going to react under twist. i think the floor as an independent entity will isolate the majority of movement and you should consider construction adhesive and hard fasteners through the floor into the already installed furring strips.

...screw everything into the floor... i would not if this means the metal floor of the van (see above)

I cannot give floating floor opinions in vehicles because I have no experience. i wouldn't use carpet for housekeeping reasons - same with individual planks or tiles, but plenty do and are happy. i'm a sheetgoods person (commercial grade vinyl - no joints or seams)

watch some youtubes how people have dealt with this. take everything with a grain of salt and use your judgement for the final decisions.

 

[Ozarker]

Initially, any plywood floor can squeak especially T&G, glue the joints heavily and don't nail. Voids in the lamination of plywood can cause squeaks, until they are worn away, some can last forever, so get the best you can find.

That foam insulation is going to squeak any place it touches wood, the tighter it is the louder the squeak. I would not use furring strips, because of that issue as it would need gluing those seams. In fact, I wouldn't use foam board at all in a floor unless it was a structural panel. Lay reflex first on the floor, depending on what your flooring is, a vapor barrier, then at least 1/2 or 5/8 plywood. Then flooring and as Southpier suggested, sheet goods are best for non-squeal flooring.

When laying wood next to each other I use a 16 penny nail between sheet goods to ensure they do not touch at all, bathtub caulk seals the joint so that flooring doesn't show any seam, spread it out, fairing it over the seam. It won't squeak and it's plyable.

You can build the cabinet with a bottom, you don't need a floor under it all the way to the wall. That can mean 4 foot ply can cover the walking area, A strip at the back of the cabinet levels the cabinet to the forward floor. Fill in the sides that aren't covered by cabinets using the penny trick.

I'd suggest you attach the cabinets at the front bottom and sides of the floor, attach to the wall as well.

I understand the modular concept of removing a camping unit from the van, but the floor needs to be attached to prevent it raising up in an accident, not that the entire floor can fly up at you, but the things attached to the floor can then break lose and fly at you. You can use a cable and eye bolts on the floor attached to a wall or uncovered floor, like those safety straps for tall furniture used by parents with little kid critters.

Last thought, in luxury vehicles you'll find that the flooring (carpet) rolls up at the bottom of the wall, I've taken plush carpet up 10 inches to a trim board, but sheet goods can roll up an inch or more to keep liquids from seeping below the floor and causing issues, mold, mildew, stinky stuff, channel away from the walls out the back or side doors for clean up.

PS. if you bond foam to plywood, use 3M adhesive and spray for full coverage.

 

[mrsa111]

Good info, thanks! I spent so much damn time on that furring strip/foam board floor it feels wrong not to use it! The insulation factor was a big reason for going that route. Even moving the floor around taking it in and out of the van it didn't hardly squeek, if anything it was extremely quiet. I think going with 1/2 inch foam board helped there because it flexes and gives a lot easier. Not much surface area in contact with the wood.

I'll have to think about this for a little bit, if I want to redo the floor.. sounds like your concept is very well thought out. The big thing I like about not using my furing strip floor is the ability to screw down anywhere in the floor.

In terms of securing the floor down, the side of the floor where the sliding door is, can be secured down by using some 90 degree metal lip. Same thing at the rear door. Both spots of the van floor have a decent size lip I don't mind drilling through that. It leaves the whole other side of the floor unsecured though.

 

[southpier]

... I spent so much damn time on that ( __________ - fill in the blank) it feels wrong not to use it! ....

this is something I believe we all deal with at some phase of building.

sometimes you need to cut your losses.

sometimes the material can be salvaged and used in another way.

sometimes you don't turn back and regret not doing so.

again, only you can make the right decision for you.

http://forum.expeditionportal.com/threads/164181-1-Bored-Clerk-s-DIY-Camper

 

[mrsa111]

this is something I believe we all deal with at some phase of building.

sometimes you need to cut your losses.

sometimes the material can be salvaged and used in another way.

sometimes you don't turn back and regret not doing so.

again, only you can make the right decision for you.

http://forum.expeditionportal.com/threads/164181-1-Bored-Clerk-s-DIY-Camper

I mean I feel like I did a good job making a floor with the attributes I want. If I just plain screwed up it'd be much easier to re do it!
I may just weight the floor with some tires or something to simulate the weight of a counter and cabinets, hit some rough stuff, get the van to flex a bit and see if it squeaks. I trimmed the spots where it was still touching the walls so hopefully I eliminated it. If it doesn't squeek I think I'll stick with what I got. Run some rubber weather stripping and/or neoprene between the floor and walls and rubber washers where the cabinets will bolt into the floor.

Im planning on spending a week or so next summer to remove the cabinets and floor to check on everything anyway. So if the floor ends up not not working out I can redo it then. Ive been debating between using vapor barrier or not, and decided against it. With the thinking that moisture WILL end up in the walls and floor no matter what I do to avoid it, and I don't want to trap it. So I REALLY want to have a good look at it in case that ends up being a bad decision!