I recently bought a 1970s double wide in Florida. The subfloor is OSB and has soft spots. The carpet is old and nasty. I know the place is water-tight now - no leaks from walls or ceilings. I want to put in good quality vinyl floor - the roll type- in the kitchen and bathrooms.
I am also going to put a garden tub in the bathroom, a water bed in the master bedroom and a set of built-in bookcases in the living room. Naturally, I want to beef up the floor.
Since this is Florida, I won't be able to insure the place for more than the (very low) purchase price, so putting a lot of money into the unit isn't sensible. Depending on the age of the mobile home in Florida, your insurance coverage can be limited and only one company in the state offers it for a unit this old. I also figured since mobiles are being given away down here, that I'd never be able to sell even a nicely finished place.
Would putting 3/4 inch plywood throughout - on top of the existing OSB - be a reasonable approach? I don't want to have to deal with having to level off patched sections. I also have a terrible sense of balance these days and am afraid of falling off the joists and breaking a leg, so I'd be hiring day labor for any needed removal of the full floor OSB.
And if I can just layover plywood, how difficult is it to build up the through-the-floor AC/heating ducts?
I've built 2 houses (with my family) from the ground up, and restored an old Victorian on my own, so I have the skill sets to do most of the work myself. I will need to hire day labor to help with the muscle work since I am an aging and rapidly becoming decrepit reg. nurse. (Hence the desire for a water bed and garden tub with jets!)