can i use fiberglass resin with strands to create a floor in a fiberglass boat with out using marine plywood if the fiberglass resin is 1 inch thick. their is expanding foam in the base in the hull of the boat the original floor was a thin coat of fiberglass over the top of plywood. that ply wood has rotted. i am trying to exclude the plywood altogether even marine grade would eventualy rott again. i want to compile coat after coat of fiberglass resin to create the new floor. the new floor would be 1 inch thick throughout the whole boat. will this support regular use without cracking. the boat is rated four people. Can you tell me how much resin I will need I an covering 40 Square Feet At one inch thick. Please email me back at justintime4444449@gmail.com with any questions or answers. thanx
Justintime
You need the plywood. Pound for pound the plywood is much-much stronger then using only fiber-glass. In fact, just 1" of fiber-glass mat on a weight bearing floor is not going to hold. It will flex, weaken, crack, and give way.
I don’t know why you are opposed to "marine plywood"… other then cost – and if that is the case, your 1" thick fiber-glass resin will be ridiculously more costly. Besides, if you are using this for a floor, you only need a good solid exterior A-B grade plywood anyway.
With today’s boat resin in boat building epoxy, if you laminate your wood, and totally encapsulate it with epoxy… IT WILL NOT ROT !!! No, not in your lifetime, your kids lifetime, or their kids lifetime.
I have been building boats using plywood for almost a half century… With today’s high tech boat resins, if you "paint" your plywood (saturate it, encapsulate it,) so that every tiny bit of it is sealed with an epoxy layer… IT WILL NOT ROT !!! In fact, it will be impervious to weather, water, air, bugs, worms, and disease (no air).
I am telling you that if you have a bit of rot on your boat today, it is a result of bad craftsmanship and or quality control.
I have dozens of 4′ x 8′ x 1/4" plywood that has been laying flat on the ground outdoors, that I use as a walkway around my boat building frames. This stuff is standing in water for a day or more after each rain, then covered in thin mud as the rain drains off. It has been there for 15 years. Now and then, I take my power washer and wash it off, and I tell you the wood looks brand new on both sides.
Use the wood, just laminate it first with a layer of epoxy on both sides, all corners and edges. then put a layer of fiberglass on that… you will have a stronger longer lasting floor – I guarantee it.
Besides, what you are talking of doing is going to cost you a small fortune in epoxy.
Don’t want to take my word for it? That’s OK, and understandable… So, check out the link below, and read what they have to say about boat resin and boat building epoxy… If you want a strong "forever lasting" floor, this is it…
Happy & Safe Boating,
John
http://boatwrights.org
call +639165155200 or +639228841821.
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first i pulled up the old carpet in one piece so i can trace out the pattern on the new carpet . i u purchased marine grade carpet. once i pulled out the old carpet i saw that the plywood floor was badly rotted. so i purhcased new plywood & cut out the same outline then i treated it with thompsons water seal. the next day i screwed the plywood floor in & fiberglassed it.
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