Plywood vs MDF for garage cabinets - one is way more stable

I built shelves out of both last year and the MDF sagged bad within 6 months even with extra bracing. The standard 3/4 plywood is still flat as a board with the same shelf spans. Anyone else have MDF shelves droop on them?

2 comments

2 Comments

riley_bell4d ago

Yeah I totally did that thing where I thought "hey MDF is cheaper and smoother, what could go wrong" and now I've got these sad little waves in my garage shelves that look like a funhouse mirror. I put a few heavy boxes of tools on one and it bowed so bad I could've used it as a skateboard ramp. My plywood ones from the same build are holding up fine though, even with the same span. Lesson learned the hard way I guess.

jamiekim4d ago

Wait, you actually used MDF in a garage? Like where humidity changes all the time and you're putting heavy tool boxes on it? That's wild to me, man. I had a buddy do the same thing and his shelf basically turned into a potato chip after one rainy season, he could have rolled a marble across it. MDF is just compressed cardboard dust with glue, it never stood a chance against garage conditions. Plywood's got actual wood grain holding it together, that's why it's still flat after a year.