5/8" HDPE sheets for rear or total floor repair?

[Bob Blarney]

Hello, does anybody have experience with this material? Obviously it is rotproof. I don't think flexibility would be a problem, considering that it overlays the frame and fits into the channel. The only downside I can think of is that the finished floor materials would need mechanical fasteners, or buy the textured surface and leave it 'as is'

The cost is $231/sheet. The shipping from CA would be prohibitive, so I would look for it locally.

https://www.interstateplastics.com/H...calculate.y=18

[sgschwend]

My guess is that being plastic it will be plastic and not stay flat. The sheet you show is only 12" wide? That is big bucks per square foot.

Wouldn't it be better to just ensure there are no leaks in the exterior system?

[Isuzusweet]

I looked at this type of board when i re-did my subfloor, however I decided against this type of board for a couple of reasons.

1) expansion and contraction. These boards can expand and contract by quite a bit, leading to broken fasteners, elongated holes, possible damage to the C channel, etc, etc.

2) Weight, these boards are very heavy.

I eventually went with Coosa board; 40-45% lighter than plywood, no expansion or contraction problems, with the added bonus of no rot, mildew or fungus.

http://www.coosacomposites.com

Cheers
Tony

[Bob Blarney]

Originally Posted by Isuzusweet

I looked at this type of board when i re-did my subfloor, however I decided against this type of board for a couple of reasons.

1) expansion and contraction. These boards can expand and contract by quite a bit, leading to broken fasteners, elongated holes, possible damage to the C channel, etc, etc.

2) Weight, these boards are very heavy.

I eventually went with Coosa board; 40-45% lighter than plywood, no expansion or contraction problems, with the added bonus of no rot, mildew or fungus.

http://www.coosacomposites.com

Cheers
Tony

After I posted, I ran across Coosa Board. It looks like the right material for the job, but the price is steep.

[Isuzusweet]

Originally Posted by Bob Blarney

After I posted, I ran across Coosa Board. It looks like the right material for the job, but the price is steep.

You most likely will have to get 3/4" board as I did; it was the thickness that my supplier stocked. I didn't have a problem machining the ends to slip into the C channel.

Sometimes in life you get what you pay for; yes, Coosa is expensive; never having to do the job again and never having to worry about water leaks.......priceless.

Anybody that has taken my suggestion has never regretted it, and has been just as impressed with the product as I am.

Cheers
Tony

[AlbertaBound]

I went with the HDPE on the leak prone front and rear. $140 for a 4x8 sheet. It is readily available in my area. Coosa board and marine plywood do not exist in Alberta. Weight is definitely increased but 200# extra was not a concern with my build. Fastener holes need to be enlarged to allow for expansion. I am going with a floating floor in my build. Been installed for 4 years with no noticeable issues. I would have gone with the Coosa board if it were available here.

[bradt]

I used Coosa-28 board (extra strong version) and it worked great. I spoke with the applications guy at Coosa factory. He had previously contacted Airstream to recommend Coosa-28 for new construction at the Airstream factory. They were not interested.

It is so easy to work with. The 5/8 size is special order. I wanted to make progress so compromised on 1/2" that was in stock. Glad I did. It is plenty strong and the 1/2 size was easy to get into the track around the edges. I bought 1/8 aluminum flat stock at Lowe's and tapped it in place to make a tight fit. I got delivery in a few days. It came protected by 2 big 4x8 sheets of cardboard which I used to make templates. The 4.5' x 8.5' pallet up on saw horses made a great work surface to cut the Coosa-28, too. It cuts, drills, sands & shapes, staples, nails & screws just like plywood. No special tools required.

I just replaced one section of rotten plywood in the rear and the Coosa-28 was perfect for that.

Coosa panel is manufactured in Pelham, Alabama and is sold only thru distributors. I purchased thru Total Plastics, Inc (TPI). They have a warehouse with inventory in Michigan. They transferred my sheet to their Knoxville office for no charge, and then shipped via freight to me in Atlanta. Jackie Jefferies 865-981-1701 was very helpful in sales and quickly processed my order and arranged for the transfer and shipping. I used anti corrosion coated floor screws from etrailer. They became flush with the surface when tightened.

[Bob Blarney]

I agree that Coosa board is the material of choice. I'll consult Management about the elasticity of the budget. There is a Total Plastics location nearby - one of the advantages of living in the detroit area is that there are many suppliers of automotive materials.

Here's a past discussion that I wish I'd found sooner. It is informative.

http://www.airforums.com/forums/f36/...on-108679.html

[ROBERT CROSS]

Had a friend use THIS when re-coring his boat.

Bob

[nevermoor]

Hi fellows.

I am trying to purchase a couple of boards of coosa 28, and only can find coosa 24 in NY. The dealer thinks the coosa 24 will that work. Will it or is it significantly a weaker product for the subfloor application? He can get coosa 26 from Florida at a huge shipping cost. I guess my question is which coosa board should i get to replace the subfloor in the front and rear ends of my '64 globetrotter?

sooooo many thank you's!!
diane

[Isuzusweet]

Maybe things have changed but I was sure Coosa came in 26 and 20 lb densities.

I used the Coosa 20, as the shipbuilders I talked to said it would span 16" easily with no deflection. If you can get 3/4" 20lb sheets (most places stock these) and just machine down to size with a router, the outer 1-3/4" part that fits into the channel, you should be just fine.

FYI I have more subfloor deflection with the OEM marine plywood than the Coosa.

Cheers
Sidekick Tony

[nevermoor]

mornng!

i like your idea about getting the 3/4" and routing down. he does have 3/4" in stock. any special considerations in routing the fiberglass composite? other than respirator, etc.?
many thanks sidekick!

diane

[Isuzusweet]

Originally Posted by nevermoor

mornng!

i like your idea about getting the 3/4" and routing down. he does have 3/4" in stock. any special considerations in routing the fiberglass composite? other than respirator, etc.?
many thanks sidekick!

diane

No more than routing Marine ply which has epoxy in it. It just creates dust. If you can, use a tablesaw hooked up to an air evacuation system.

You won't regret buying Coosa.

Cheers
Sidekick Tony