1972 27' Overlander - subfloor repair

[goodcardio4u]

I discovered (so far) an area(about 12"x6") of the subfloor under laminate flooring that is rotted away (black) it is below the window next to the front door - looks like it creeping inwards.
I will find out soon how far the rotting goes into the trailer.
Can I take a skill saw and just cut out (in a nice square) the rotted 3/4" plywood (I assume thats what was used to build it) an replace it with 3/4 in plywood square the same . It might require a very large square, maybe 4'x4' who knows, and maybe also near the sink and fridge/hallway, 3'x4' dunno. Any tips? I thought I read that after 1969 the flooring is inside a C channel, you dont have to pull the shell to replace it? I saw one bold head -- do I have to pull the belly pan too? cut off bolts? Is there a work around?
Thanks
Dan

[sgschwend]

You should be able to repair the floor from the top.
The flooring would need to be removed, then you can cut your rotten wood out. If you remove small squares first, you can reach in and find the frame edges. It is better to get the hole close and then mark and make your final cuts.

Try to get the replacement plywood to land halfway on top of the frame steel, then you can bolt it into place.

You also want to know where your tanks are, to make sure they don't become damaged. I think my tanks are about 1" below the bottom of the floor.

[goodcardio4u]

Awesome, thank you so much for that piece of info - thanks to you - going forward with confidence - God bless and may peace be with you today , no matter what you do. Dan

[ALANSD]

Most of these older models had wood rot near the front door. It may also be in the back or sides under any vents that might have leaked. I would check all that and cut out what you have to replace. If it is only confined to smaller areas, check the frame underneath after you cut out the floor, and see if it needs reinforcement or replacement.
I had some minor rust, which I cleaned up, then sealed the frame with POR15. I scabbed in new plywood and then sealed all the wood around the edges of the whole interior with wood sealer, I forget which brand.
If you find any leaks under the vents or vent tubes, be sure to get up to the roof and reseal the vents.
I did this to my 66 4 years ago and have not had a leak since. Also check behind the refrigerator as that vent may leak too...ask me how I found that out!

[goodcardio4u]

Great info , thank you so much. I suspect a leak 2ft from front door where aftermarket awning was attached , could be window , dunno. I'll start taking up all laminate floor and see what I got. So how did you find your roof vent leak? I figured I'll use garden hose or high pressure to check for leaks. Thanks in advance. Dan

[ALANSD]

I could see where the water had run down the wall. IN the bedroom it ran through the vent over the storage bin, and left messed up veneer all the way down the wall. I replaced the covering. Replaced the vent cover also, and sealed the vent cover with Vulkem.

[ALANSD]

here are some photos. One is the cover over the ceiling attached vent pipe on the bedroom The old one was shot due to water damage. I managed to find 3" Oak and stain it to match the surrounding wall wood.

The other is the vent pipe itself, which I sealed outside and then sprayed Flex Seal up inside all around it. I need to trim out the cabinet bottom over the pipe covering...

[goodcardio4u]

Great ideas , thank you immensely - going forward with confidence - Dan

[ALANSD]

do so you will always have support here. Like your user name! I am self-cured of Cardio-Vascular disease. It was an interesting journey through the medical establishment. Yikes.

[goodcardio4u]

Thank you so much . I'm still into demolition , discovered - looks like some leaking below a window - I guess reseal the outer frame of window? Seal skin joints / seams? Not sure what bead to run on seams and window frame - maybe exterior clear silicone seal - thin /small clean bead?

[ALANSD]

No No silicone ever. It is hell to get off aluminum and not recommended. Get some Vulkem which you can order online, it's grey colored non silicone. You can also buy Gutter seal from Lowe's. Buy a few animal syringes, the large plastic ones. Squeeze the sealant into the syringe and apply with that, to get a smaller bead.This bead will do well in the seams and around the windows.
I also use blue painters tape to outline the area to be sealed. That keep it clean and straight. Then you peel it off afterwards. Clean up with mineral spirits.

[goodcardio4u]

Good deal , thanks again, I'll let you know how things progress (although I'm laid off, I still have to work till end of May - so work gets in the way of progress)