Plywood vs MDF for a workbench top in my damp garage

I spent three evenings weighing a 3/4 inch birch plywood top against a sheet of premium MDF for my new workbench in Seattle where everything stays wet half the year. I went with the plywood because I was scared the MDF would swell up like a sponge the first time I spilled coffee on it. Now it already has a slight warp after two weeks and I'm wondering if I should have just sealed the MDF and saved forty bucks.

4 comments

4 Comments

rosek4421d ago

MDF in a damp garage is a NIGHTMARE. I tried it once and the edges puffed up like a marshmallow in a microwave. You made the right call with plywood, but warp means you probably didn't brace it enough underneath. Throw a coat of shellac or poly on ALL SIX SIDES of the plywood and cross-brace the hell out of it.

the_olivia21d ago

My uncle Garry tried plywood in his garage workshop back in 2008. Same story as yours @rosek44, he didn't seal the edges and the whole thing bowed after a rainy spring. He ended up cutting out the warped section and replacing it with two layers of plywood glued together. Worked fine after that, but he also put a dehumidifier in the corner. That helped more than anything. The plywood itself is fine, you just have to treat it like it's going to be sitting in a sauna.

morgan_butler21d agoMost Upvoted

Read a blog post where a guy used marine plywood in a Florida shed and it barely warped after a hurricane.

noah88021d ago

My buddy Dave in Portland built a workbench out of 3/4 inch MDF about five years ago and sealed it with three coats of spar urethane. Looked perfect for almost a year until a pipe dripped on the corner for a weekend while he was out of town. That corner turned into a soft, crumbly mess that looked like wet cardboard. He had to cut off about eight inches and patch it with plywood. So honestly, I think you dodged a bullet with the plywood even if it warped a little.