Linoleum over plywood- is there a flexible crack filler?

KYErik · Sep 9, 2007

I have just replaced the floors in a mobile home with 3/4" plywood and would like to lay linoleum directly over the plywood without going to the extra $ expense of adding another "smooth" layer of something like luan on top of it.

I already have the rolled linoleum, but there are some 1/8 " to 1/4 " cracks between a few of the plywood sheets as well as some knot holes here and there. I would use bondo or drywall compound and sand smooth, but, this trailer will eventually be moved and I am afraid that flexing during transport might crack bondo or drywall compound.

Any ideas for a slightly flexible, non shrinking crack filler that would end up smooth enough for the linoleum to lay on top of? What about silicone caulk?

This is a 30+ year old 12 X 40 singlewide so it doesn't have to be perfect.

ultrarunner · Sep 9, 2007

I worked in Floor Covering long ago...

Here are couple of things I remember:

1. Leave a gap the size of a dime between sheets of underlayment to allow for expansion

2. Larger imperfections are smoothed over with Vitex or Fixall.

3. Plywood is OK as long as it doesn't have voids in the laminated layers... void can give way. Sheet goods sold for flooring will not have voids.

4. Be sure to follow the nailing schedule around the perimeter of the sheet and check to make sure that adjacent sheets are solidly attached to the sub-floor... i.e. no independent movement.

5. The heavier "Inlaid" vinyl floors such as Designer Solarium by Armstrong will cover over many imperfections... the thinner "Printed" type floors will show imperfections. If you are not sure, just look at the vinyl from the side... does the top layer extend well into the product or is it only on the surface.

6. Use the right adhesive for the job... i.e. concrete, above grade, below grade, wood, etc.

7. Use the proper notched trowel to apply adhesive... the notches on the trowel control the amount of adhesive going down.

8. Many adhesives require a few minutes breath time to out gas... at least they did back in the day when I was putting down floors.

9. Make sure the surface is free from all dirt... a few chips of sawdust will telegraph through and look like a mountain.

10 If possible, leave the vinyl in the same room overnight so that both product and floor will be at the same temperature.

11. If you are still concerned about the gap... I think an Acrylic Latex caulk might be better than 100% silicone.

elalexander · Sep 16, 2007

Hi Erik. I did the same job a few years ago and the place I got the vinyl recommended I use a leveling compound. It mixes with water and you fill the gaps and cover your nail heads with it. It kind of reminded me of a skim coat of drywall joint compound. It didn't cost much and I think came in a 1 or 2 lb. box. My floor still looks good.

Hope that helps, Eric.

KYErik · Sep 17, 2007

Thanks guys!

I'll check on the "fixall" or leveling compound to see if it can take a little flexing (when the trailer is moved) without cracking up. I'll use acrylic caulk on the deep/wide gaps.