Pulled the rear seat out of the old girl for a winter project, seems a little overkill to use 3/4 inch marine plywood, what do you guys suggest? and who sells it?

This stuff looks cool -- anyone know how much it weighs relative to wood?
http://www.boatoutfitters.com/store/...tic-Sheet.html

Heavy- per their shipping cost estimator a full sheet of 3/4 is 210lbs. Hope that's wrong.....

Exactly why I'm asking, on the manufacturer website they also have a lightweight version as well...but I'll have to look up strengths of the material, weight vs. wood etc, hell if I can save a little weight over wood why not if it's not tons more money...

I haven't even started pulling the carpet, speakers or vinyl, so now is the time for ideas

Here's another option,

http://www.coosacomposites.com/

I think what you want is PVC foam board. It is what many of the boat builders use today. Lighter than wood, can be heated and bent, glues easily and takes staples.

It is about $150 a sheet for 3/4 down here. I'm not sure who will have it up there. You also can buy it at a lumber yard as Azek trim board.

Here is a great description

http://www.bertram31.com/proj/tips/pvc.htm

For the cost of some of these materials, i dont know why you just wouldnt use wood again. i am having my rear bench done because of wood rot. Not sure why Cigarette designed it the way they did, but i'm just using wood again. It lasted 20 yrs, so another 20 yrs will probably outlast the life of the boat.
by then recreational boating & gas engines could be a thing of the past.

Used 1/2" marine ply on mine. With the proper supports, it's plenty strong and a lot lighter. Stainless decking screws and gorilla glue hold it all together. $70/sheet

This is kinda where I am headed, sticking with the wood and going with 1/2 which will save me a LOT of weight right there -- same here it made it 19 years, the cost of "plastic/polymer" stuff is just way to expensive, maybe if I planned to keep it another 15 years I'd go for it...

I only had severe rot around the bottom 2-4" or so and around the seat bottom, so I am going to seal it up around the lower edge and around the lower seat cushion with something and it should be good for many years.

EDIT: and I'm just going to copy the original design supports included.

If your going to use plywood, use exterior grade. The glue will hold up better to the elements.That's if you don't use marine grade. I used 1/2' treated plywood on my sun pad, maybe over kill, but no more rot the last few inches when the drain gets plugged.

thats exactly where mine had the worst rot. i dont know why they didnt put a layer of glass over the bottom. Looks like with it being open, it eventually just absorbed any standing water. we are going to glass it all in this time.