Plywood for flooring

[Douglasdzaster]

Sorry I haven’t been on here in a while. I actually started a new thread about rebuilding the boat since that’s what this is turning into. I’ve been posting on it. The plywood is all cut to fit with penetrating epoxy applied. It’s finally cured,edges and all sealed up tight.
I’m planning on starting to put the puzzle together today.
Ill be updating the rebuild post and adding pictures.

 

[airshot]

If I'm understanding correctly, you want to be able to frequently remove the ply flooring. I'm not visualizing how you would use threaded inserts to help do that.

How about some kind of hold downs at the seat boxes. Use alum angle with a few fasteners of choice into the vertical part of the alum seat box. However, this might not work depending how the three sections of flooring are arranged.

View attachment 112899

From this pic, the plywood floor would go on top of the angle. The angle will support the weight and just a couple screws are all that is need to keep the floor in place.

 

[Douglasdzaster]

From this pic, the plywood floor would go on top of the angle. The angle will support the weight and just a couple screws are all that is need to keep the floor in place.

I have everything in place but the angle. The plywood is supported by the foam board and ribs. The angle will be used to hold it in place just Incase I need the help of the foam board to float. Lol
Also I’m tying in a couple of things to some of the angle like a platform for portable fuel tank and one for the trolling battery. That way I’m not putting any screw holes in the sealed plywood. Tried to post some pics but my net is moving slow today. I’ll try again.

 

[LDUBS]

From this pic, the plywood floor would go on top of the angle. The angle will support the weight and just a couple screws are all that is need to keep the floor in place.

From the diagram I attached, the angle would be on top of the ply - like holding the ply down. Remove the angle to remove the ply. Your approach of having the lip under the ply would provide extra support along that edge & just remove a couple screws to remove the ply. I can see the advantage. I think either way will get the job done.

 

[PriceTR24speed]

Hear me out on this one. I tested the following method extensively with my previous build. I've documented it here somewhere a long time ago. Been awhile since I've posted.

It's been mentioned to use foam between the ribs. For sure do this - it should be 1-1/2" thick to build up the floor to make it even with the ribs. This will provide all of the support for weight of humans and gear that you will need. After this you don't have to worry about what weatherproofing method you are going to use on plywood or what type of plywood to buy. Instead of plywood, go out and buy yourself a sheet of 3/4" foam insulation - the same stuff you just used between the ribs except in 3/4". The weight of this stuff is practically zero. This is what you are going to lay down as your finished floor. Cut this to fit your floor side to side and front to back. To make it look and feel nice and to protect it you can now use either marine carpet or vinyl. Cover the surface by gluing the carpet or vinyl down with flooring adhesive and wrap it around the sides to the back where you will again glue it and then staple it. Yes the staples will want to pull out but they are not there to hold it down - they will hold it laterally until the glue dries and that will glue the staples in place as well.

What I have just described is to use foam insulation board wrapped in carpet for your floor. It has no structural properties so that's why you need to have a flat supporting surface underneath it by filling in the voids between the ribs with foam. "The foam is light and will blow out of the boat going down the highway!" you say. All it takes is a panhead screw - I used exterior grade cabinet screws, and you screw through the carpet and foam and into the floor ribs - make sure they're not too long to protrude all the way out the bottom of the boat. A regular screw will pierce the aluminum rib all by itself, no need to predrill. A couple screws in each rib will keep this floor in place.

This floor weighs nothing other than the weight of the carpet and it is completely weatherproof. It's a nice padded surface to stand on all day too. I did my whole boat - floor and decks in this fashion - I only substituted plywood of the same thickness anywhere that I knew I would need structure like for a trolling motor or a hatch lid. I even glued plywood and foam board together edge-to-edge and wrapped it in carpet all as one piece. The boat got used by me and a friend 2-3 times a week for 3 summers like this and the foam board has held up better than the plywood areas. No, it does not "crush" or flatten under weight. No, the screw heads do not pop through - the carpet prevents this. You simply have a small dimple where the screw is. That's it.

You want a light weight and maintenance free deck or floor - use foam board.

What adhesive did you use to attach the carpet to the foam board? Can you use the spray adhesive or do you need the water based carpet adhesive? I am using the vinyl flooring over 1” pink foam board. I love this idea and am trying it now for a portion of floor that will be temporary to get me through this bass season. Right now I have it all put together with just staples to test fit and they are more secure than I expected.

 

[Douglasdzaster]

What adhesive did you use to attach the carpet to the foam board? Can you use the spray adhesive or do you need the water based carpet adhesive? I am using the vinyl flooring over 1” pink foam board. I love this idea and am trying it now for a portion of floor that will be temporary to get me through this bass season. Right now I have it all put together with just staples to test fit and they are more secure than I expected.

I put the foam board between the ribs then 15/32 plywood that I cut to fit in three sections used penetrating epoxy coating the edges really well. Once cured I used tnuts wide stainless seam plates to tie the three sections together on saw horses. Then I screwed in male snaps around the edges. Oh the t nuts and snaps I screwed in I used 5200. With the plywood assembled on the saw horses I cut the carpet and installed female snaps to match the plywood. then I took it all apart and it goes in the boat like a puzzle. No adhesive on the carpet and plywood completely sealed. I cut short pieces of aluminum angle and painted them. They attach to the boat with the bottom of the angle on top of the floor holding it in place. Just a few because the weight on top is going to keep it in place gear ,trolling battery , portable fuel tank all have to ride on the floor.
Now I have a floor I can completely disassemble in a few minutes to keep the bottom of the boat cleaned and debris free and inspected for corrosion.
Sorry I can’t help you with what adhesive is best. When I made the seats across the rear bench (now storage and electrical compartment) I used plywood foam and marine vinyl. I used Gorilla spray adhesive and it worked great on the foam. Good luck and make sure you have fun building your boat the way you want it.

 

[thill]

I am using the vinyl flooring over 1” pink foam board. I love this idea and am trying it now for a portion of floor that will be temporary to get me through this bass season. Right now I have it all put together with just staples to test fit and they are more secure than I expected.

Not sure if you know this, but vinyl shrinks after installation. I don't think it will work attaching it directly to the foam. It will pull out after awhile. You might want to attach it to some FRT (?) thin fiberglass board or something similar, and put that on top of the foam.

 

[Weldorthemagnificent]

I have had great luck with exterior plywood and Thompson's water seal. My boat is budget with a drop in deck. I see you've chosen epoxy and a floor covering which should look awesome. As with any boat, storage is key. Not under a tree and bow up and plug out! If you keep it well drained, the floor should outlast your interest in the boat.

 

[Douglasdzaster]

I have had great luck with exterior plywood and Thompson's water seal. My boat is budget with a drop in deck. I see you've chosen epoxy and a floor covering which should look awesome. As with any boat, storage is key. Not under a tree and bow up and plug out! If you keep it well drained, the floor should outlast your interest in the boat.

I went and got an awesome cover with motor cover attached since I can’t keep it inside. I’m drawing a blank but it was from Carver and one step down from Sunbrella. Used pvc pipe and T fittings for legs every few feet and made a ridge the length of the boat. Looks like a long tent and along with the coating water doesn't hang around anywhere.

 

[-CN-]

What adhesive did you use to attach the carpet to the foam board? Can you use the spray adhesive or do you need the water based carpet adhesive? I am using the vinyl flooring over 1” pink foam board. I love this idea and am trying it now for a portion of floor that will be temporary to get me through this bass season. Right now I have it all put together with just staples to test fit and they are more secure than I expected.

I used the carpet adhesive. Not sure about spray as it may eat the foam.

 

[Smokey101]

Heed the above advice.
In my opinion, if you want the wood to last longer, stay AWAY from carpet!
Why? It holds water.
I’ve had both vinyl and a “liner” (think truck bed liner). In various boats. Both shed water, neither hold water. Neither where slick when wet, both cleaned easily. Blood from both me and fish, coffee, soda, all cleaned easily.
For my current boat, I put in EVA foam. Time will tell. First time using it.

That is why I stay away from carpet, all nighters on the boat catfishing can leave a mess with all the nasty stinky bait I use, if the mess won't clean up, I just apply another coat of paint

 

[Douglasdzaster]

That is why I stay away from carpet, all nighters on the boat catfishing can leave a mess with all the nasty stinky bait I use, if the mess won't clean up, I just apply another coat of paint

I put my carpet in with snaps so I can pull it out and pressure wash it and dry it before putting back. As soon as I where it out doing that I think I’ll go vinyl. My plywood is treated with a lot of penetrating epoxy and should out last me.

 

[Livn]

I had to look up RTD plywood. Looks like it is replacing CDX in home constuction. It is rated for mild moisture contact.

I wouldn't use it, even glassed in. 3/4" is probably overkill and heavy. Use foam between the ribs for flotation and floor support. If you have to use plywood, go 1/2" exterior grade, ACX. If the foam sheeting is the same thickness as the top of the ribs, you can go with a thin sheet of aluminum. I went with 0.040" thick aluminum over foam more than 10 years ago. Still going strong.

Does it get hot?

 

[Douglasdzaster]

Does it get hot?

What I did doesn’t. And I’ve had it out in triple digits here in Texas. Stays cool under bare feet.