Replace wood boat deck with Aluminum?

[Swimmer]

My deck is showing the effects of water and age...like me. Anyone here replaced their plywood decking with aluminum? We use a product at our shop called Alpalic that is two thin layers of aluminum with an acrylic sandwiched between and only about 3/8" thick. Are there other sources of sheet aluminum that others use?? Or should I stick to using Marine grade plywood?

[gunflint]

I don't know anything about aluminum decks. But I replaced my deck this winter with marine grade plywood. The lumber yard recommended 1/2 inch because (they said) that's what everyone uses. If I ever do it again I'd go with 5/8ths

[Swimmer]

Why would you go with 5/8? Sag? I guess the reason I'm sonsidering alu is to lighten the ship. She is an '89 Tracker guide V-16 with only a merc 25 on it...and they loaded it with decking...so pretty heavy for its "size". I know...time to buy a new boat. But hey, I like projects.

[gunflint]

My boat was converted to a deck years ago by someone that knew what they were doing. But he only had 6 cross supports over the 10 or so feet of the deck. It had 5/8ths in there but I didn't know that when I ordered the 1/2 inch. Because it was a special order I couldn't return it. Lumber yards are very proud of their marine grade plywood and don't give it away. I think it was about $100 for 2 sheets. It should be fine and I'll be trading it in, in a year or so. But I like to do things like that right. The weight difference between 1/2 inch and 5/8ths is negligable.

[Steve Bakken]

Honestly, guys, marine-grade plywood is overkill. For the additional cost and weight, the benefits are negligable. The only place the boat manufacturers even use it is on bare bench seats and dash panels. In the 20+ years that we've been installing floors and decks, we've never had a properly prepared installation rot back out. And I stress that the key word here is "properly prepared". We've always used BC grade plywood and we treat the topside with a resin coating before laying the carpet and it holds up to the elements as good as marine grade does at a fraction of the price and weight. Just make sure that you penetrate all exposed surfaces with a resin-based carpet glue before laying the carpet and you should be worry free.

[MinnesotaMuskie]

A little unorthodox...

I have an old 16 foot Lund. A friend traded me the boat for a couple week at my cabin. The floor and the rod storage was a bit rotten. As I dug into it...the entire floor was trash.

I take the boat down a lot of "roads less traveled" and to Canada alot. The carpet was always dusty and crappy. I took a chance and replaced all the flooring with Cedar Decking???

I looked at a Whaler at a boat show and stole the idea. I used the torsk head screws, self tapping into the cross supports. Where a support was absent...I used treated with gorilla glue. I made a casting deck over the rear seat that will lift off...not real conveienet...but it covers the gas and batteries nicely.

I used an electric planer to match the sides of the boat. I love it...I used a very thin piece of aluminum as a spacer. Rain goies right through to the bilge...slime and other yuk can be rinsed off easy. The decking was much lighter as well.

I have only had it in a year...so I cannot vouch for the longevity...but everyone that has seen it has been impressed:)

[Z-man2002]

MinnesotaMuskie, do you have any pictures of that cedar floor you could post? I'm thinking about replacing the floor in my boat,sounds like a good idea.

[cheesehead]

I used a similar approach to cover the splash well on my 16' smoker craft. my rear deck was only 12" wide by creating the cover I almost doubled my deck space on either side of the motor. I cut some notches in the supports and use velcro to hold them in place.

mine have lasted for 3 years now without any problems. I would assume that properly caed for a florring built this way would last as long as your house deck.

[Surface Tension]

Steve suggestion about the BC plywood and resin coat is right on. Something else to consider when covering a floor is keeping all the sand and organic crap from getting under the floor and plugging the weep openings in the ribs. Having that water trapped between the hull and floor is not a good thing. That moister will stay there and condensate on the bottom of the floor deck and in time will rot the floor out from the bottom up. Something that helps is to open up storage compartments to get an air flow when the boats not in use. Also if you have a wood floor, get everything off the floor when not in use. If you notice most areas that rot first is in the stern where the gas can sits.

Thats because that spot is never allowed to dry out.

[EBass]

Is that like the MDO plywood? That's what I used for my redecking winter project. 5 layer 1/2" MDO from Siwecks or something lumber in NE MPLS. 30 bucks a sheet. I told the guy what I was doing and he said not to use marine grade and to use MDO as it's twice the product for half the price. Then I had my buddy seal coat it and put in some silica sand for grip. No carpet this time so I should be able to spray it off. I really want to take it out this weekend to see how she handles. Mine is heavier now than it was before and I to have a wee lil 25H.

[MinnesotaMuskie]

Z-Man...I am taking my boat in the heated shop tomorrow:)...Getting ready for Stugeon fishing...I will take some pics and try to post here.

[Swimmer]

Ceder decking...hmmm...interesting. I'm trying to picture it, but it sounds like it would be cool just for the novelty of it. Let's see some pics!

[primetime49]

Swimmer not only is it a great idea to use aluminum it willalso make your boat lifetime and you will not have to do this repair again,never use marine grade plywood as most of it sold now days is made to be signboard standing straight up and down and not subject to being a floor with moisture retained underneath it .also you cannot paint both sides of it if you lay it flat as it will maintain moisture it becomes a wick and moisture can not relieve itself.probaly want to use diamond plate intead of your sandwich kind from work and use either heavy duty big head rivets or pre drill your wholes slightly undersize and add locktight if you choose to use screws.we switched to these two methods after fasteners failed on several brands of mn builtt aluminum boats,they do it to now.half inch plywood verses five eigths only 20 pounds difference if you go that route.but why fix a problem with a problem

[Swimmer]

Prime: thanks for the input. Where, how much, would you go to find the diamond plate.? The stuff, hi-tech sandwich, from work, is free, but only 3/8". Do you know if they make Stainless steel Tech screws?

[primetime49]

if free is ok with you than use it but you will have a slippery surface and may want to add carpet or puke pad,screws check a fastenal store or automotive parts store .the reason i suugested pre drill and locktight is that several mn boat mfrs have gone to this past couple years,3 8 ths is fine

[Swimmer]

Thanks again Prime. Ya, I would be gluing carpet onto the sandwich aluminum. When I get the old decking off, I also plan on searching out a small leak (riveted boat) using the fill the boat up with water trick. Any experiece with this? Once the source of leak is determined, should I have it professionaly repaired, or can a backyard bungler handle the job? How does that meltable epoxy stick stuff work?

[Steve Bakken]

anything you put on or over the leak will be a temporary fix. The rivet needs to be re-compressed. It should be do-able in your backyard provided you've got a buddy to work on the other side of the rivet.

[castindad]

steve on the floor of aluminum boat i put a primer. looks real good question is doe it need to be covered with ????? primer is water base. enamel? castindad ps aluminum floor thanks

[Steve Bakken]

Most of the time, with the exception of catylized and epoxy primers, they need to be topcoated. They're not designed for durability, uv protection, etc. They're just the adhesion and prep coat for whatever paint your applying.