l am looking into getting a pontoon but it needs a new floor and l wanna know what l am getting into. My husband and l are both pretty handy but l just wanna make sure that It wo not be above and beyond what we are capable of. Any advice would be appreciated.

you can, but it is best to remove the old first, you are adding weight and if you just cover the existing floor it will hold 1 less person, if not 2

That would be fine as long as you do not mind cracks inbetween the wood. Also depends how your going to keep it down. Staples? Nails? Glue? make sure your staple/nailing it into solid material.

do not use the old plywood, it will not hold the new properly, take it down to aluminum, replace it with marine quality, not just outdoor, live long and prosper.or at least, get to use your boat.

remove all the old lumber first & go to menards or home depot & get water proof lumber or make it out of fiber glass if u can so it dont rot make sure u put some slip guard on the deck to keep people from getting the skids watch where u drill the holes so u dont hit a fuel line or a electrical wire make sure u put access doors in it if need to be to get at the wiring,cables,fuel lines etc or u will be ripping it back up it should be easy for u both to handle look at other boats to get some ideas

if u do not mind re-doing it again in a couple years, go ahead & put good wood down over rotten wood. rot is a bacteria that wo not quit as long as u keep feeding it.

marine ply is way expensive & hard to find in some areas. For decks & floors in my boat l used B/C exterior grade, saturated in poly resin, with one layer of fiberglass cloth. the fiberglass adds a lot of strength for the weight.

Coat ur fasteners in 3m 5200 or some other marine adhesive sealant - otherwise it is the beginning of rot already. A bit more trouble but a bit better sealed - drill out holes for the fasteners, fill 'em in with epoxy, then fasten through epoxy - no water gets in at all.

Remove everything. Install an aluminum deck and bolt it back together!

Always remove the old floor before replacing it and then you can reinforce the mounts for your seats also

Here l go again. putting my 2 cents worth in when u already have a good answer. jtexas is on the right track,
but maybe l can help u out a bit more & save u some extra effort & a little money.

It is true, that what causes the rot in wood is bacteria & like termites, it is a living thing & would just love u to hand feed it a new supply of fresh out of the oven new ply.

Sure, it would be easier to nail down some new on top of the old, but if u do. it wo not last very long at all & rather than it holding up over the old, the old will be pulling the new ply down with it, with the year.

You can use tongue & groove ''good on one side - exterior grade'' plywood. & l would use 1 inch. some pontoon manufacturers only use 3/4'' but most of the better ones use 1''.

Now, here is where ''jtexas'' & l disagree.
You do not want ''poly'' resin, u want to use boat ''epoxy'' resin. l would go to ''US Composites'' they r online & l have included the link below. & order their ''635 thin epoxy resin & hardner''. u will need to order a medium or slow hardner depending on where u live & the temperture.
What u really want to do is laminate, every single tiny molecule of that plywood on both sides. & on the corners & edges with boat epoxy resin. l would apply two coats. one penetrating coat, & one laminating coat.

Now. this stuff is expensive. at the link below, u will pay $61.00 a gallon & that will be a gallon of resin, plus another quart (or so) of hardner is included. This is the very same stuff as West Marine is 101. If u go to West Marine, or some other local Marine outlet, u will pay near twice this amount.

Depending on the size of ur pontoon boat, u will need probably 3 or 4 gallons. l use a large squeegee & a paint roller to apply the stuff. It goes on like paint.

If u saturate the plywood on both sides & on all the edges, l assure you, u will never again have to replace that floor as long as u live. nether will ur great grand kids.
You do not need to fiberglass it. no need whatsoever. The fiberglass cloth is not only expensive as well, but, since u r laminating a solid deck, there is no real advantage whatsoever to laying fiberglass.

l have forwarded u two links. one is to US Composites, where u can buy ur boat resin. l have used these people for years & never once had any problem. in fact, l get all my resins, fiberglass, supplies from them.
The second link is for Glen-L boat building. now l know u r not ''building'' a boat - but they sell boat building plans & on their site (somewhere - u will have to click on a few links to find it) they have a wonderful pictorial - tutorial with good tips on how to use, mix, apply boat resin to plywood.
So, good luck with ur project.

Happy & Safe Boating!

http://glenl.com/

http://uscomposites.com/

You could put it right over the old, but when you have it stripped down that far go ahead and take the floor out also. It is rotten anyway, and you most likely do not want the added weight. This is a relatively easy job, l have done it a couple of times, taking everything off is the tedious job. Tip: use tongue and groove, marine grade plywood and your floor will lay nice and flat.

if the wood under neat is not that bad go over it with s.s.screws