Underlayment needed for vinyl plank flooring?

[Greg1410]

I am getting ready to install my vinyl plank flooring. Should I install an underlayment or vapor barrier? My friend in the floor business says no, but of course he does not have experience with trailers. He is concerns about trapping moisture with the underlayment.
Thanks,
Greg

[lonewolf1977]

From what I've read about vinyl plank (and this is what we'll be using as well) is that you don't need one....just apply to the subfloor.

[sb55]

From my experience putting it in unheated lakeside cottages in Northern Vermont and my own Airstream, not if you get the all vinyl planks. Some are only vinyl on the top layer, and that may be different.

[Wconley]

FYI, we installed some "click-lock" wood grain vinyl flooring in a '65 Shasta we restored. We didn't install a vapor barrier but did find that expansion/contraction from temperature swings pulled some of the seams apart. Several attempts to get those seams to permanently lock into place were futile.

[kevinkatz]

We had bamboo in our 65 caravel and when I took it out there was a thin foam layer that I left in place and started installing the vinyl click plank. I very soon realized that the plank kept separating as I walked on it because of the give from the foam. I took out the foam and put it straight on the plywood. It then stayed together well.
I would not put anything under vinyl plank.

[Larry C]

No underlayment is needed, just apply directly over the plywood floor....just make sure when you "click" them together the pieces go together tightly. I use a piece of hardwood about a foot long, put it on the edge of the last piece, tap it with a hammer, to assure the joint is tight.
I've installed flooring in 4 Airstreams like this, haven't had a problem yet.

Larry

[ldireland]

I installed vinal plank in our 2003 Classic 30 without any underlayment which is how the instructions say....but then....it also said it is not suitable for RV installations due to the swing in temps. Ours had an initial shrink but then grew back into place. It averaged itself and looks great. Easy to install in an afternoon.

[carl2591]

what time of year did you go install, temps etc. and was the vinyl accumulated before hand.. also what flooring did you install..??

thanks

Originally Posted by ldireland

I installed vinal plank in our 2003 Classic 30 without any underlayment which is how the instructions say....but then....it also said it is not suitable for RV installations due to the swing in temps. Ours had an initial shrink but then grew back into place. It averaged itself and looks great. Easy to install in an afternoon.

[rodsterinfl]

My LVT plank is now two years. I laid it over the vinyl that was there. I also hunted for a brand with ultra low expansion rating. Everything looks ok though I have noted some lift at the points where I cut the vinyl underneath to inspect the floor and stapled it back. No separation though.

[luforia]

Current original floor is in good condition, but would like to have more customized feel without adding a lot more weight. I'd like to put vinyl planks (from Costco) over original instead of ripping it out, is this okay?

[drairstream]

All about the weight. I'd take it out.

[Whigmi]

When applying to subfloor is it okay to go right over plywood staples and screws with the LVP? An installer said to nail it down the staples which seems like a lot of work for glue down vinyl planks.

Thanks!

[J. Morgan]

I would go over the old floor.... but thats me.

Are there staples in newer Airstream floors? That would surprise me a lot.

[kevinkatz]

I would remove the old floor to reduce weight. The thicker vinyl planks that are not glued but just clicked in place, are forgiving to imperfections in the floor. I would only hammer down really raised staples or nails. I think that the thicker, more expensive, vinyl looks much better and especially with time. It is a small area so the difference in cost is not great and not having to deal with messy glue is a huge plus.

[J. Morgan]

What does the old floor weigh? 40lbs? 200lbs?

[Whigmi]

I have removed the carpet, and now there is just the plywood floor. I am calling them staples which join the plywood, but maybe there is a more correct term for them (picture attached).

The flooring I would like to use is a 3mm glue down.

https://www.mohawkflooring.com/Vinyl...ood%20Chestnut

Thanks so much for the help!

[J. Morgan]

Originally Posted by Whigmi

I have removed the carpet, and now there is just the plywood floor. I am calling them staples which join the plywood, but maybe there is a more correct term for them (picture attached).



The flooring I would like to use is a 3mm glue down.



https://www.mohawkflooring.com/Vinyl...ood%20Chestnut



Thanks so much for the help!

I Don’t know what they call those little curly wafers either..... lol I am sure they have a name....

[pvfjr]

If they're the same as mine, I usually see them called corrugated fasteners or joint fasteners at the stores.

[kevinkatz]

That’s a pretty floor. I would make sure that any floor is fully vinyl and not a combination of wood and vinyl. There is a good chance your floor will get wet and also deal with a good amount of humidity. The good vinyl floors can actually be soaked in water and not be affected.

[Whigmi]

Thanks so much! Yes, I believe it is all vinyl which is why I liked it so much. It isn't real thick which is also why I thought it had the potential to poke up from the staples. Another thought was installing another thin sub floor. This might help with the height difference in the bathroom as well. Right now the bathroom floor which runs through the center of the trailer is about 1/2" higher.