Type or grade of plywood to use for decking?

[Birds]

Why type, or grade, of plywood do people recommend to use for decking on a train board? Sheathing grade, B grade, A-1 grade?

I finally tracked down a source for Homasote - 30 miles away. None of the folks working at the nationally based home center stores had even heard of Homasote.

Enjoy,
Birds

[lionelsoni]

I use BC, with the B side up. But I fasten my track directly to the plywood. If you're going to cover it with homasote or something else, I don't see why CDX wouldn't do.

[Anonymous]

OSB would also work and is often cheaper than plywood.

[dougdagrump]

Birds, If homasote is difficult to get how about 2x4 ceiling tile. It won't hold fasteners as well but if you use ballast with white glue the fasteners shouldn't be an issue.

[c50truck]

Birds,
The BC will give you the best face for the lowest cost if your attaching right to the plywood. CDX works fine if your covering it. Also check around. If your cutting the plywood to smaller pieces, buy mistrim plywood. Any Independent lumber source will have it, not sure if the big box carry it. Can save some change.

Homasote is also known as "Building Board" or "Sound Board". Should be readily available everywhere. The white-faced version of Homasote is used by many as bulletin board material.

Rod

[jefelectric]

One caution, if you are using CDX, is to make sure your benchwork is very sturdy as most of the CDX you get now days will warp something awful when it is brought into the house due to temperature changes. I actually used AC on my last layout to get a more stable product. OSB is actually more stable but not as strong. You need to install it on bench supports no less than 16" spacing in my opinion. OSB has replaced plywood for most uses in home construction.

One other point, unless you are talking to an oldtimer at one of the big box stores they probably won't know anything about homosote. You are better off trying to get it at a local lumber yard.

[Sturgeon-Phish]

My choice is OSB. It has a rough side and a smooth side. You can actually screw closer to the edge on OSB than 3 ply plywood. Construction techniques has 24" on center with 1/2" OSB. With the quality of plywood going down I use OSB almost all the time. Lays flatter and takes moisture better.
Jim

[Birds]

Thanks for the input guys! Lots of good information.

This gives me plenty to work with as I shop.

Enjoy,
Birds