Hardie Board Overlay

[onacreek]

Any opinions on repairing water damaged flooring on a 1963 Globetrotter (leaking water tank) by first removing curbside and front sofas and water tank and then partially removing the most severely damaged / pliable wood, then filling in with a DAP cement leveling material, and finally overlaying all exposed plywood floor surfaces (except the galley and bathroom / shower area) with 1/4" hardie board?

After that I am thinking of applying linoleum sheet.

I just want to make the trailer functional, not perfect.

Will this work?

[qjktx]

Sounds heavy - the 1/4" material weighs 2.6 pounds per square foot.

- Mark

[onacreek]

Originally Posted by qjktx

Sounds heavy - the 1/4" material weighs 2.6 pounds per square foot.

- Mark

Haven't measured the total area, but i am guessing about 60 square feet - (around 150#)

Would it be just as good to use a good quality plywood over a leveled floor? I didnt think that the incremental weight would be prohibitive, and the hardie board will never rot.

[malconium]

How seriously damaged is the sub-floor plywood?

Malcolm

[onacreek]

Originally Posted by malconium

How seriously damaged is the sub-floor plywood?

Malcolm

It is seriously bad right at the front, beneath the water tank (i could just pull it all out by hand) condition improves as you move away from the front. The extent of the damage ends at the rear side of the door (maybe 4 feet from the front).

[markdoane]

I would replace with plywood. I don't think Hardie board has the mechanical (bending) strength that plywood has.

[malconium]

I think that I agree with Don. It sounds like you basically have a hole in your floor. Does it extend out to the edge of the floor or is it basically just a hole more in the middle of the floor? It should be fairly easy to just cut the rest of the bad wood out and cut a new piece of plywood to fit the hole. Depending on exactly where it is you would likely just have to add some plywood strips under the edges of the patch that you can glue and screw to both sides of the joints. I suggest about 3" on each side of the joints for your plywood splice pieces. Use a good grade of waterproof wood glue and some decking screws. This type of joint is pretty much as strong as the original plywood. This is also how AS recommended repairing the floor in my 1973 shop manual.

If you decide that you want to use some sort of overlay on top of your subfloor to give you a better base for flooring then you might want to consider 1/4" underlayment plywood. It would be a lot lighter than the hardi board and could be made more waterproof with some type of paint or sealer if you want. Also your choice of flooring could help with the waterproofing.

It is also possible, by the way, to get Polyboard in 1/4" thickness. I don't know if you have read any of the threads about my use of Polyboard to replace my subflooring but it is a totaly waterproof material that is a lot more flexible than Hardi board would be. It would make a fantastic floor underlayment. I just checked pricing today and 1/4" Polyboard at my local supplier goes for $41.35 per 4 x 8 sheet. Polyboard prices have gone up since I bought mine by the way. If you are interested in checking out the Polyboard take a look at the following thread:

http://www.airforums.com/forum...ad.php?t=14620

I believe I included information there about where to get it.

Malcolm