Layer cake like floor...will it work?

[stonyfork]

So...I've poured over every post on cork floors and luan underlayment (as in the ol' Luan Skin For New Floor Thread), and am still unsure if my plan is a good idea, or a wolf in sheeps clothing.

After pulling up the carpet and examing the existing subfloor (the original plywood from all appearances) and marvelling at how solid and relatively unburdened by water damage the subfloor is, I felt good about my plan to go with a simple 6mm cork underlayment followed by 12x24 cork tiles, both glue down using water based contact adhesive as recommended by cork supplier/manufacturer. But then I noticed the subfloor was pretty rough (i.e not smooth) and the joints at the frame were not as level as I 'd prefer since I want to minimize any telescoping of unevenness through the cork. Even after hitting the bolt heads and joint seams with wood filler, I couldn't get the smoothness that I wanted.

So I thought I'd just add a layer of 1/4" plywood (birch) to get a smooth surface to proceed with the cork.

I plan to have these layers (1/4 ply, 6mm cork underlayment, cork floor tile) stop 2 inches short of perimeter walls, which will have a frame of sorts of oak 1x2's screwed to subfloor which I can remove to check for moisture/water intrusion each spring and fall. And am not removing cabinetry but cutting in and around.

The benefits seem to be:
a) get the smoothest substrate for the cork
b) would be easier to remove IFI ever had to since the cork is only adhered to the 1/4" ply and not the subfloor itself
c) adds a little firmness to the 5/8" original subfloor.

Only disadvantage I can figure is extra cost and time. Unless I'm missing something...am I?

[stephenh2]

I'm thinking of doing the same thing, so I'd like to hear what folks say... How are you planning to fasten down the 1/4 plywood? Will you use a staple gun?

Stephen

[stonyfork]

1/4 Ply is down and prepped. Cork underlayment goes on tomorrow, weather permitting. Used combo of screws and nails to secure the 1/4 ply.

[hampstead38]

It's how we did our floor. I overlapped the seams on the 5/8" with the 1/4". I didn't use screws... just glue and used weight to clamp the pieces. It's not going anywhere. I have a nice surface for the cork and extra density makes the floor less springy.

[adwriter73]

Originally Posted by hampstead38

It's how we did our floor. I overlapped the seams on the 5/8" with the 1/4". I didn't use screws... just glue and used weight to clamp the pieces. It's not going anywhere. I have a nice surface for the cork and extra density makes the floor less springy.

I am thinking of doing this too and wondered why you chose to overlap the the seams instead of lining up the luan with the existing subfloor seams. How is it holding up? My worry is that the trailer flexes at those subfloor seams, which could crack the floor on top of it.

[triplenet]

From my experience from remodeling, I would overlap the joints to give you a more stable base and use a 1/4" crown staple without glue.

I installed vinyl tile over existing sheet vinyl.
I had a few bumps in our floor from protruding bolts heads, cabinet removal, etc.
I brushed my hand along the floor and when I felt a bump, marked it with a marker. Then came back with an angle grinder with sanding disk. It was quick and easy.

Bob

[adwriter73]

Originally Posted by triplenet

From my experience from remodeling, I would overlap the joints to give you a more stable base and use a 1/4" crown staple without glue.

I installed vinyl tile over existing sheet vinyl.
I had a few bumps in our floor from protruding bolts heads, cabinet removal, etc.
I brushed my hand along the floor and when I felt a bump, marked it with a marker. Then came back with an angle grinder with sanding disk. It was quick and easy.

Bob

Sounds like a good idea. So staples and not screws? I know you just did this, but have you run into any issues since you installed the new floor?

[triplenet]

Screws would be OK also. I have an old pneumatic stapler, it's much faster.
When I've hired underlayment put down, they really staple it, I'd guess at least 4" at the perimeter and every 6" in the middle.

I didn't need to install underlayment on my coach as the vinyl was in pretty good shape.
We installed the new floor to change the color.

Bob

[Aage]

stony,

I'm guessing by now you have finished the floor, would you care to share some photos of it with us?

As for negatives, there will be weight gain, compared to the old flooring. I don't think it is a reason to panic, but I would keep in mind as you do other things that it's nice to renovate without making a significant change in the trailer's weight...

[hampstead38]

The 1/4" is pretty flexible. I don't see it breaking unless the entire frame buckles.

While the 1/4" ply adds a bit of weight, we're losing weight in places. The planned cork flooring weighs less than carpet and pad (particulary when wet). The Magic Chef oven was a boat anchor (that is now gone). We've eliminated some of the storage space. We've used poplar for interior framing. The inflatable Sleep Number bed will weigh less than the pull-out double.

As for fasteners, I used screws in a few locations around the edges where I though separation might occur, but I didnt' go nuts on fasteners. The glue I used will outlast the trailer.

[adwriter73]

I put down a layer of 1/4 floor underlayment (luan plywood, i guess is what is). I used 9/16 size crown staples. Seems pretty secure but I'm wondering if I need to secure it more before I add the next layer of floor. Also, there was one seam that i didn't cut perfect and it left me with about a 1/4" wide, 4" long gap. Can I fill this with wood putty or just leave it alone?

[bobfowler]

Originally Posted by hampstead38

The 1/4" is pretty flexible. I don't see it breaking unless the entire frame buckles.

While the 1/4" ply adds a bit of weight, we're losing weight in places. The planned cork flooring weighs less than carpet and pad (particulary when wet). The Magic Chef oven was a boat anchor (that is now gone). We've eliminated some of the storage space. We've used poplar for interior framing. The inflatable Sleep Number bed will weigh less than the pull-out double.

As for fasteners, I used screws in a few locations around the edges where I though separation might occur, but I didnt' go nuts on fasteners. The glue I used will outlast the trailer.

You're the first I've seen that is using a Sleep Number bed in their trailer. We use one at home - I love it!

[dnrtheil]

Does Luan stand up to water the way exterior grade plywood does? I would guess that when the Luan gets wet it'll swell up.

Derek

[hampstead38]

I used a thin ply, but I also treated it with three coats of serious waterproofing. I'm sealing the edges with a clear silicon bead and putting cork tiles down (eventually). The way I see it, if I get enough moisture in to degrade the thin plywood... I have a pretty serious problem.

[adwriter73]

Originally Posted by dnrtheil

Does Luan stand up to water the way exterior grade plywood does? I would guess that when the Luan gets wet it'll swell up.

Derek

I'm doing a test. I cut a 12" square piece and soaked it with water (more water than it may ever see) to see if it delaminates and how much. Going to check it tonight to see what happened.

[hampstead38]

Let us know how it goes... but I don't think luan was ever designed to be soaked.

[maison1306]

The carpet is out in my 2001 Excella, 30'. Was going to use 1/4" lauan but installer felt we should go to 3/8th's plywood. A little heavier but not that much. Not sure how they"re attaching it- either nails or screws. Then installing sheet of special moisture barrier over the wood. Then installing Mannington Adura plank vinyl flooring (3' X 5" X 1/8 thick). It will be glued to the moisture barrier with a special glue that will allow a plank to by heated with a hair-dryer and taken up if damaged and replaced.

Using the 3/8th's plywood also eliminates having to use any trim around the edges because the carpet and pad were cut away at the edge of cabinets and dinette. The 3/8th " hides the cut-away edges.

Hope it works ok.

[AirHeadsRus]

Whatever they attach to the floor, make sure they do not use nails or screws longer that the thickness of the floor. There are water lines, electric wires and black & grey tanks down there just under the floor. Someone attached a 1/4 in plywood to lay flooring and it hit a water line. Must have sat there for years slowly leaking. When I took the floor up to install a new floating floor, I pulled the nail and it looked like a little spring flowing from the hole. Big problem getting that fixed without dropping the belly pan.

[maison1306]

Good info to know about water/electrical lines under the floor!