Simple Floor Ideas?

[LaqueRatt]

I have a very basic aluminum fishing boat. Think it's what you call a deep V. It's a bit difficult to walk around in. Especially towards the front where it's deep and narrow. All I'm after is making it a little easier and safer to walk around. Don't want to add much weight, don't want to permanently attach if don't have to.

Read quite a few threads on line, I kind of know what not to do. Everyone says that pressure treated lumber, maybe exterior grade plywood too, will basically dissolve aluminum. Is this an exaggeration? Almost sounds like an old wive's tale, but there is probably some truth to it. I'm not so sure though that plywood has anywhere near as much chemical treatment as decking lumber. Even so, if I put enough coats of oil paint on the wood shouldn't that keep the chemicals away for at least a few years? If not, maybe I'll just use #2 pine with a bunch of paint on it. If I did this I could just make it out of 1x6, maybe with spacing between them. In sections that could be lifted out. Would it stay pretty much in place by itself or does it need to be screwed/riveted down? The boat is a 14' Mirrocraft that has never had a floor in it.

My transom also has been "re-done" using pressure treated lumber. That has to go ASAP right? I'm just hoping it hasn't been on there too long. Again can I cheap out and use standard plywood glued in layers to build up thickness, drowned in oil paint or maybe fiberglass resin? This is such a simple boat I don't really care if have do this over in a few years. I'm just looking to make it better now. I may not even still have it by the end of summer.

 

[alldodge]

No expert; but why not 1/2 CDX plywood and coat both sides with fiberglass cloth and resin

 

[Ned L]

I would probably use something a bit nicer than CDX, but that would work. I’d look for maybe a BCX.
Regular exterior plywood has no preservatives in it so it is fine to use.
If you don’t leave the boat outside & full of wet leaves just a couple of good coats of oil based paint (like Rustoleum) should last 5, maybe 10 years +.
A word of caution,…… Adding a sole (deck) will raise the center of gravity and may well turn “walking around” up forward into a bit of a balancing routine.

 

[LaqueRatt]

I agree CDX can be kinda rough. Sort of depends though. Sometimes it's not all that bad. I do think though it would be worth a few extra bucks for BCX which normally has one side that is pretty flawless. The "X" though means exterior. Does that mean it has the chemicals that will eat into your aluminum? What I'm thinking of as a floor is something that will sit low on top the existing aluminum. Hopefully not throwing off the center of gravity too much. I don't even know if it has to go fully side to side. A level "runner" down the center would work just fine. Maybe only a foot or so wide.

 

[briangcc]

The X for plywood is that it uses an exterior grade glue to laminate with so that when hit with water it doesn't come apart like interior grade plywood would. Perfectly fine for boat use - many have used this in rebuilds of their boats.

I personally would stay clear of any pressure treated lumber in a tin barge - just asking for trouble based on past restos.

Water + pressure treating chems + aluminum = holes in aluminum boat.

The pressure treated stuff I get in my neck of the woods is dripping with chemicals. Totally soaked. I would wager a year minimum of drying time to get it to a point where paint/shellac might stick.

As for anchoring the floor - yes you would want to do this. Leaving it loose means hitting a wave could bounce it up in any direction - including yours. Could be a painful learning experience. Could also shift underfoot causing a man overboard situation.

 

[garbageguy]

One of our boats is the same as yours (14 ft aluminum, although labeled Alumacraft).
It's never had a floor, but it has been considered. Have considered a partial-floor aft and mid (not forward). The discussion here reminds me of that partial-floor idea. But maybe that's a weight-distribution issue

 

[airshot]

Have added floors in small tinnies many times. The best, cheapest, and user friendly floor is made by either buying or find a local machine/ fabrication to bend you some simple aluminum or stainless steel angles as long as necessary to span the length of your tank seats at a height you want your floor. You then attach these pieces of angle with screws or pop rivets to the tank seats...Now measure between each seat to get the size of plywood you will need for the floors. If you measure and cut carefully you can get all your flooring from one 4x8 sheet. You need a 5 ply exterior plywood that is a minum of 1/2" but 5/8" is even better! The 5/8" has almost no flex with my 200 lb butt .. But I have used the 1/2" with good results just more flex under weight. Paint, carpet, or what ever to the plywood. Once cut to fit inside the angles you added to your seats, a few screws will hold it in place!! The screws allow you to take it out for cleaning or retrieve lost fishing tackle if your clumsy like me. In the forward most floor nearest the V I added a small hatch, dropped in a bucket and had a nice little anchor locker !! If you want yiu can add a shelf on each side, level with the seat top, makes a great work surface to mount rod holders and sonar units.....
This is the quickest, easiest, cheapest way to add a floor to a V bottom tinnie and it works great !! Good luck with your project..

 

[LaqueRatt]

The advice I've gained from this site sure has saved me some headaches and this floor project I'm sure would have likely not gone well if I just winged it. Thanks for all the details airshot. I don't suppose you have a picture of your boat with floor installed? I'm especially curious about what you did in the very front.

So you didn't need to install any additional bracing? The floor just sits on top the brackets? Also, could galvanized brackets be substituted for stainless or aluminum? I do think though I can likely fab some alum brackets myself. I'm pretty good at working with metal and got a few short pieces of scrap 4x4 alum that might be sufficient for the project if I cut it right.

 

[Scott Danforth]

yes, chemicals in pressure treated lumber will dissolve aluminum by electrolysis.

ACX or BCX plywood is fine

if you dont want to add much weight, flotation foam and PVC foam board works to. you will need to use 4# foam vs 2#

would keep any brackets aluminum

 

[airshot]

The advice I've gained from this site sure has saved me some headaches and this floor project I'm sure would have likely not gone well if I just winged it. Thanks for all the details airshot. I don't suppose you have a picture of your boat with floor installed? I'm especially curious about what you did in the very front.

So you didn't need to install any additional bracing? The floor just sits on top the brackets? Also, could galvanized brackets be substituted for stainless or aluminum? I do think though I can likely fab some alum brackets myself. I'm pretty good at working with metal and got a few short pieces of scrap 4x4 alum that might be sufficient for the project if I cut it right.

Nope, only use aluminum or stainless, no galvanized material !! There were no center supports in any of my flooring builds. If they were larger boats with floors spanning a bigger area then they might be needed. If I had two people that weighed 200 lbs each standing in one spot then mabey a center support, but in a 14' boat that is highly unlikely !! My last 14' was sold about 16-17 years back, I know there are pics of it somewhere, just have to find them. As far as the front goes, just create the flat floor then due to the V hull, there will ve quite a bit of space under the floor in the front. I found a bucket about the right height, cut a hole the dia of the bucket, dropped it in...instant anchor locker !! Dont over think this floor project, it is really quite simple. Use a home made straight edge to figure where you want the floor and how high or low from the bottom of the boat. Adjust your angle brackets accordingly. If your tank seats do not go to the floor, then adjust the length of one side of your angle to get the floor height just right. I used 3/16" aluminum pop rivets to attach the aluminum angle to the tank seats, then SS screws to attach the plywood floor to the angle. Using a 5 ply plywood adds much strength to the plywood and wont buckle like 3 ply will. Keep us posted on your progress.....

 

[LaqueRatt]

I doubt if I'll be doing this anytime real soon. I know, spring will be here before we know it, but right now pretty much in the planning stage with a lot of small boat projects. Thing that concerns me most is my transom. It's not done very well, appears to be too low and I'm not 100% certain, but suspect it's treated lumber. I need to get that off of there before it messes up my boat. I sure wish had a picture of how the transom originally looked.

So 4" foam is solid enough to support a person's weight? Seems a bit fragile, wouldn't it need to be covered with wood?

 

[alldodge]

4 pound foam, the type you pour in and it expands

 

[airshot]

Sounds messy and expensive, plywood sounds so much easier...if you had a flat floor like a jon boat then plus one on the foam board !!

 

[RMClark]

I have a 14' Lund, vintage 1979. It had plywood decks between the benches and a casting deck in the bow. The decks between the benches were getting squishy when I bought the boat in 2020. No idea how old they were. The casting deck was, and still is, solid.

I decided to replace the decks before the 2022 fishing season. I was fortunate enough to be able to use the pre-existing decks as patterns.

Pic of the deck when it's in place:



Pic of the underside:



The deck is 3/4 ply, because that's what I had hanging around the shop when I did it. 5/8" or even 1/2" wouId save some weight. I cut the ply to match the old deck, added the center support and the ribs. The center rests on the ribs that span the boat side to side. I cut the shallow notches to allow wiring to cross underneath without being pinched by the center support. The whole wood structure is coated in resin. I spent some time fussing with contact points to get them just right so the floor doesn't rock. The covering is cheap indoor/outdoor carpet from the home improvement store.

Regarding the OP's transom...I'd tackle that first just to make sure that the work replacing the decks isn't wasted in the event there's a nasty surprise in there. Since it's known that the transom is treated lumber, I'd dig into that first to make there's not an out of control corrosion problem. Having decent decks to stand on is optional, a solid transom is mandatory.

Good luck, and I hope my explanation of my solution helps in some way.

 

[LaqueRatt]

Impressive carpentry skills man! So I'm guessing with the 3/4" the weight holds it in place? Yeah, now that I know about the issue with treated wood and alum I'm a bit worried. I need to see what can do about that. I'll probably start another thread on that subject and hopefully somebody with a boat like mine will post a picture of how it's supposed to look. It's quite a hack job and I was thinking about re-doing it just because I don't like how it looks.

 

[RMClark]

Impressive carpentry skills man! So I'm guessing with the 3/4" the weight holds it in place? Yeah, now that I know about the issue with treated wood and alum I'm a bit worried. I need to see what can do about that. I'll probably start another thread on that subject and hopefully somebody with a boat like mine will post a picture of how it's supposed to look. It's quite a hack job and I was thinking about re-doing it just because I don't like how it looks.

Thanks. The decks are not fastened down. The ply was sized to be about 1/4" short of the fore bulk head and the aft bulk head. That allowed room for the carpet to be overlapped of the edges. So, the deck fits snugly when lowered into place. I have to use a small hook to wedge under the deck edge to pry it up when I need to.

I've considered adding L brackets to firmly affix the decks down, but I haven't really sensed a need for that, yet. The lakes I fish are typically 1-2 hours away and the travel is via highway, and I've had no issues with the decks bouncing or otherwise becoming dislodged.

If I add the L brackets, I'll also add some flotation under the floors. I removed some of the foam under the benches to create space for tackle boxes, batteries, and some storage for miscellaneous items like drift socks, marker buoys, rope, and required safety gear.