I have a late 1970 Starcraft Tri-hull.  Its mainly used for catfishing, shooting carp, snagging, etc.  Was checking out the boat today and noticed what I think to be a small (3" x 24") rotten spot in the floor.  Can I expect the rest of the floor to start going to here soon?  Will this affect the boat at all other than having a soft spot?  Does it need to be fixed?  Are there any cheap fixes?  Since its an older boat and its used mainly for the type of fishing that its going to get dirty anyways and we didn't pay much for it just don't want to put to much money into it.  That and I'm saving all the money I can for a bass boat this winter.  Thanks

Actually, a 24" long section of flooring that's soft wouldn't exactly be a "small" section of flooring.

Considering your usage of the boat, I'd really hate to tell you to start tearing things up. I'm afraid you'll probably find more internal damage (water logged flotation and a rotted stringer(s)  than what you're feeling.

Since it's basically just a junk type boat used for blood sporting I wouldn't mess with it till your foot goes through the floor. At than point I'd just lay some new wood over it and not get much further involved.  

Do you want to restore this for the fun of the restoration?  If not, just temporarily fix the problem.  Once it is a real problem (IE your foot goes through the hull) just take the motor off, keep the trailer, and throw it in the front yard with a sign that says FREE.  Or put it on Craigslist, as a 400 dollar trailer with *free boat*

But, if you put a piece of plywood over it, it will last quite a bit of time.  More than you would think.

Sorry to bring this back up as I'm just getting around to working on the floor.  I have decided to just lay another sheet of plywood down on top of whats already there.  With the amount it gets used and what its used for I think its probably the way to go.  Do I go ahead and put plywood over the parts that aren't soft also at the same time?  What would be the best plywood to use for this and what would be the best way to secure the plywood down?  Anything else I need to know?  Thanks

If you are going to put ply over the old why not remove the old and just have the new ply.  I would use 3/4 inch ply to fix it.  Cut it to shape seal it with something then screw it down in the boat.  The old deck is probably screwed to the boat.

Good Luck,

Tom D.

It is not a bad job to just replace a section. Cut out the spot, lay in the new and glass it in. Do not use treated material if you are glassing. Fiberglas has a bad habit of not adhering to it. Use regular plywood and glass it up. You will be fine.