I want to start making my own hives, traps and nucs. Of all the plans I have looked at, a lot mention using plywood. What kind do they use, treated or nontreated. If using plywood for such things as nucs, traps bottom board and inner cover. Since this is not water proof, doesn't it rot faster.
it depends on wehe that plywood will go, and what it will be exposed to, AND how well it is painted, and maintained.
It is hard to seal end grain on plywood, but it can be done.
Inner covers using plywood will last quite a LONG time, depending on if you let condensation build up in your hive, and if you do, you usually end up with dead bees.. so the inner cover is a great place for plywood.
I also use plywood on the tele cover top, and the bottom board. Both with pine boards around them.
Tele cover, WELL painted, lasts five years or so.. With metal.. lasts five to six years... I seem to be getting a lot of moisture between wood and metal, and its hard on my tele covers.. Bottom boards are lasting 4 to 6 years well painted.
Making all of my own hive equipment, means that the tele cover and bottom board cost me about 4 dollars each to build. I make extras each winter, and usually sell half of what I made.
If you cant make your own, and dont want to pay to replace them every few years, then use something that does not rot.. Cypress for example.. (Old Cypress, not young growth) or Cedar, and keep it well painted, it will last you quite a long time. There is also PLASTIC hives if you don't want to worry about rotting at all.
With a couple of hives, it should not be hard or overly expensive to replace the old parts every so often.
It also depends on your location. Down here in N Florida, I made a bunch of bottom boards out of 3/4" plywood. By the third year, I had to replace all of them. Luckily I had made them so that they could slide out. It made them much easier to rebuild.
Jim
Longevity is an issue, to be sure, but there's one other feature about plywood that's seldom mentioned - it's density.
As is well-known, plywood is manufactured by compressing layers of veneer and glue together under great pressure, a process which produces a relatively heavy and dense material - at least when compared with lighter softwoods - and one which has poor insulation characteristics as a result.
Does this matter ? Well - that depends on where in the world you are keeping bees, but even the hottest desert regions can be bitterly cold at night.
LJ
Some of the glue the plywood is made with has a tendency to make a toxic vapor when it gets hot in the sun.
Same with treated lumber.
I've used it numerous times, just because it was the only thing I had on hand and I was too cheap to buy more orthodox wood from the lumber store. I've used it not just on beehives, but other projects around outside. It lasts longer than you'd think. The main problem is not rotting per se, but that it swells like a wet book and loses some structural strength. That said, it's cheap and lasts longer than expected.
there are a lot of different types of plywood. you asked about treated. pressure treated should not be used. it has a lot of different toxic chemicals in it. generally the more layers the better the plywood. marine plywood & plywood that is made for concrete forms is usually high quality but it's pricey. besides delaminating another drawback is that plywood is heavy. I use plywood for inner & outer covers & traps only.