Expensive plywood

[Ted+Teresa]

So, I just got prices for the Baltic birch marine grade plywood !!!

At $170 per sheet, I am looking for alternatives. I am planning to insulate my walls. Fiberglass will finish the outside, so neither side will be exposed.

Can anyone suggest something less expensive that will hold up?

Ted

[saltydawg]

When you say fiberglass do you mean sheet goods or hand layed?

If hand layed, I would recommend MDO plywood. It has water proof glues, and a fiber paper coating so getting a smooth finish is easy. But its not as cheap as normal ply, its cost about 60 bucks a 3/8 sheet at lowes or home depot. ( not all stores carry it )

Its worth the extra cost to me for the water proof and the smooth surface.

[Tom&Shelly]

So, I just got prices for the Baltic birch marine grade plywood !!!

At $170 per sheet, I am looking for alternatives. I am planning to insulate my walls. Fiberglass will finish the outside, so neither side will be exposed.

Can anyone suggest something less expensive that will hold up?

Ted

We used 5 ft by 5 ft sheets of 1/8 inch and 1/4 inch Baltic birch that cost around $20/sheet three years ago. I imagine the price has gone up, but I hope not that much

This stuff is not marine grade, and you have to find a lumber yard that carries it or will order it. Tony Latham, on this forum, has tested the material by putting pieces in water with good results. We fiberglassed our exterior and have not had any problems so far (after six months of use and sitting outdoors in a rainy climate).

Full story is: Our wall interiors are 1/8 inch bb, the core is hogged out 3/4 inch AC plywood and foam insulation, and the exterior is 1/4 inch bb covered with 6 oz fiberglass/epoxy, primed and painted with bedliner. Roof is similar except the exterior is only 1/8 inch bb.

Tom

[DrewsBrews]

If it will be covered by other sheet goods and/or waterproofing then I don't see the necessity for marine grade. Wouldn't exterior grade suffice?

[Pmullen503]

It's more important that your build does not allow water to collect and sit anywhere. The construction details make all the difference like drip edges and drains.

[DrewsBrews]

True, When looking for lumber for the cross spars I caught myself looking for the straightest pieces. Then I realized slightly bowed boards could be used to my advantage; bow oriented outward would counteract the weight of the roof and prevent sagging that would lead to water pooling.

[halfdome, Danny]

LikeTony had mentioned, I too did a test several years ago and all the regular 1/2" Baltic Birch plywood did was to discolor.
Soaked it for several weeks in a bucket of water then put it out in the sun in a baggie then let it dry out of the baggie.
Danny

[tony.latham]

I too did a test several years ago...

Don't we do odd things in our man caves?



Tony

[aggie79]

Try "Russian Birch" instead of Baltic Birch. That's what I used on my teardrop. 12 years later, I'm still using scraps for small projects. Here're current local prices for Russian Birch from specialty wood supplier:

5' x 5' sheets, B/BB grade:
3 mm (1/8") - $20.49
6 mm (1/4") - $51.51
12 mm (1/2") - $63.52
18 mm (3/4") - $118.85

4' x 8' sheets, B/BB grade:
12 mm - $114.32
18 mm - $164.20

[halfdome, Danny]

Another high quality plywood similar to Baltic Birch is USA manufactured Apple Ply.
It comes in 4 x 8 sheets, used it for years for cabinet drawers.
Danny

[saywhatthat]

if your going to glass the out side . Why would use wood don't think about the Titanic think about an F-22. this glass foam under $100 exterior and interior skins and 1 in Foam easer than wood S

IMG_20210704_152809.jpg (168.43 KiB) Viewed 988 times

[popper]

Not much to add as a newb, except to say I see a lot of great material in the trash here in my neck of the woods. I picked up some old ply for free locally. And not necessarily just plywood, but even curbside broken cabinets, dressers, other furniture. A sawzalz can turn that into good useable chunks of wood for bracing. Save some green in your wallet and the other kind of "green" too. Try to turn them sour prices into some lemonade.

[Ted+Teresa]

Thank you all for the feedback!

I decided to bite the bullet on the outer sheets, and skimp on the inside.

Our tear will have baltic birch-marine grade on the outside walls, AC ply in the middle, skarfed and insulated, and white birch to finish the inside walls (got it on sale for $30 sht We plan on using fiberglass to finish the outside - by hand, not sheets (we own Tony's book, and will be following his advice!) .

I had not heard about the glass foam, and will research that

Also, have not heard of Russian birch nor apple ply. I will look into those options as well.

Funny, wife just talked about scavenging armoires for cabinet parts!!

Ted

[western traveler]

Ted, as one that is nearing completion on a build using Tony’s book I can say you picked a great guide to follow.
Have fun with it,
Ralph