Replacing Rotting Wood Floor

KE7JFF

Adventurer
So, I'm dealing with replacing a rotten wood floor in a toy hauler I'm doing a remodel on. Essentially, its the entire kitchen standing space at about 4 feet by 4 feet.

While I have decent woodworking skills, its been a while since I have tackled something like this. My understanding the process for the job is this:

1) Cut out all rotten sections with a sawzall tool.

2) re-enforce the floor beams if needed

3) cut plywood to fit sections

4) install new floor sections

However, I'm trying to select the right plywood for the job; should I stick with standard plywood or go with something else? I was thinking marine plywood possibly. Anyone have advice? Thanks!
 

downhill

Adventurer
Marine plywood would be good, but any multi-ply with exterior glue would work. I think the most important thing would be to seal the wood with epoxy resin or fiberglass. You can back up the edges around the hole using extra wood underneath. Do a search for drywall repair, and you will see how it is done for repairing bigger holes in drywall. Same idea. It's pretty frustrating that it needs to be replaced, I imagine. How old is it?
 

KE7JFF

Adventurer
I forgot about sealing it....I seem to remember some redneck trick with Thomson's Water Seal? Lol.

It's a 1997 Warrior; which I know they had some wood issues.


Sent from my iPhone using Tapatalk
 

downhill

Adventurer
Yea, well, I guess it just has to last as long as the rest of the floor right? :) The waterseal will help a bit, but unless you can re-apply it, it won't really help long term. I think I would saturate with epoxy and call it good. Be prepared. Once you cut out the bad area, you may find more trouble than you bargained for. :Wow1:
Good luck!
 

KE7JFF

Adventurer
Well, this is what I am dealing with
b139ef45ad5f7f62a0eda32979bfcad9.jpg



Sent from my iPhone using Tapatalk
 

colorado matt

Adventurer
I might suggest a circular saw set to cut only as deep as the wood itself .... not sure what is under the wood and don't want a long sawzall blade bouncing around under there .. the added advantage it will save any support beams that may still be good to support the old floor .... just take your time
 

dlh62c

Explorer
Your not the only RV owner that has had floor rot. Search YouTube to see what others have done.
 
Last edited:

KE7JFF

Adventurer
I might suggest a circular saw set to cut only as deep as the wood itself .... not sure what is under the wood and don't want a long sawzall blade bouncing around under there .. the added advantage it will save any support beams that may still be good to support the old floor .... just take your time

Oh no doubt...I have some shorty sawzall blades I made up for cutting into restricted areas...I'm probably going to rip up by hand the wood that is basically now paper (the black area) first to see how the supports are made up.

And I keep forgetting about pressure treated plywood!


Sent from my iPhone using Tapatalk
 

fluffyprinceton

Adventurer
Pressure treated plywood.
Consider possible outgassing with PT ply. Might just smell bad or might be a health hazard. Epoxy sealed ply is my first choice but in that location - structurally speaking - any ply is going to be better than that OSB crap. Get an oscillating multi tool - much better for the job since 1.you have excellent depth control 2.less dust 3. very precise cuts are possible.Moe
 

workingonit71

Aspirantes ad Adventure
sealing plywood floor with the"mix"

I forgot about sealing it....I seem to remember some redneck trick with Thomson's Water Seal? ....
On many forums about woodworking or trailer-building (my favorite http://tnttt.com), you'll find virtually the same method for sealing plywood (especially the porous edges). It's the "mix" of paint thinner or mineral spirits with polyurethane in varying proportions, usually 50/50 to soak into and waterproof the wood. When I built my 4x8 trailer of 3/4" plywood, I started with 75% thinner/25% poly to get maximum saturation, then 50/50, finishing with 100% polyurethane. I used two coats of each (a coat equaling saturation 'til no more was soaking in), allowing each coat to . The pre-sanded plywood I used had phenolic resin glue between plies, so I only saw penetration thru the wood where voids had existed previously, meaning that the "mix" was filling the voids inside with poly (after the thinner evaporated). I used Minwax fast-drying poly (higher VOC level, easily soluble) with cheap paint thinner. Don't use the odorless, milky colored thinner...it will not work. Apply each successive coat before it fully dries (under 24 hours; but I waited only until each coat flash dried); that way, each coat blended into the prior coat, and no sanding was needed. I poly'd my floor differently than the exterior, though, since I planned a durable, complete, floor covering for it (I used two easily removable rubber-backed floor mats, cut to fit), only using one coat of 50/50 and two of 100%. The exposed outside edges of the floor (upon which the wall sit) was treated with the full spectrum of poly mix, when the exterior was done. When the exterior poly was done (all coats), I painted it a week later with multiple coats of durable tractor or reflective silo paints, and extra coats of black paint along the plywood edges. I wanted a certain color scheme, even though I liked the look of the woodgrain under poly, and had to protect it from UV rays anyhow.I used high VOC content paint, to chemically bond to the poly, with no sanding. All surfaces have proved waterproof to date. I recommend using the "mix" to waterproof your wood floor, since it has worked so good for me.
  • exterior polyurethaned.jpg exterior polyurethaned
  • polyurethaned, painted gray (front) silver (top).jpg polyurethaned, painted gray(front) silver (top)
  • painting finished.jpg painting finished
  • carpet and threshold added.jpg carpet and threshold added
  • edges.jpg edges
 

IdaSHO

IDACAMPER
Consider possible outgassing with PT ply. Might just smell bad or might be a health hazard. Epoxy sealed ply is my first choice but in that location - structurally speaking - any ply is going to be better than that OSB crap. Get an oscillating multi tool - much better for the job since 1.you have excellent depth control 2.less dust 3. very precise cuts are possible.Moe

What he said, on all counts.

Personally, Id do epoxy coated baltic birch
 

KE7JFF

Adventurer
Thanks for all the tips everyone...

This floor job is for a trailer that was donated to the SAR organzation I belong to; while I understand the idea of sealing the floor with chemicals, an idea that popped into my head would be to roller over the floor once replaced with that Flex Seal stuff then put down some inexpensive flooring so that its double protected.
 

Forum statistics

Threads
185,527
Messages
2,875,534
Members
224,922
Latest member
Randy Towles
Top