I'm working on a DIY project for built-in cabinets and bookshelves in my office. I'm getting RTA cabinets from Cabinet Authority, which helped me tweak the widths for a consistent look. I'm planning to install a countertop, either butcher-block or laminate. I need advice on which material to use for the bookshelves that will sit on top of the cabinets.
I'm planning to build four bookshelf units, each 72" high and 35" wide. The shelves will be fixed, set in dado joints, and made from 3/4" material, so they'll measure 33 1/2" wide and 12" deep. I'm going to cut the shelf boards to 11 1/4" and add a 2" x 3/4" nosing to the fronts for extra support. The nosing and face frame will be made of paint-grade maple, matching the cabinets, with a 1/4" backboard rabbited in for support.
My main question is whether I should choose birch plywood or MDF for the bookshelves. I'm concerned about costs and the risk of sagging given the shelf widths. I've read that dado joints with MDF aren't great, so I'm considering using dowel-reinforced butt joints instead. Any suggestions on materials or modifications would really help!
4 Answers
How about trying poplar instead?
I'd go with plywood for durability. I've worked with both materials, and plywood holds up much better. MDF tends to sag over spans, especially for something like bookshelves.
Definitely choose plywood for strength if you plan to load the shelves with books!
Check out this sag calculator to help with your decision: https://woodbin.com/calcs/sagulator/. Dowels could be a solid choice as long as you use a good quality dowelling jig!
Thanks! I tried the sagulator and it looks like the nosing will keep sagging within acceptable limits for both plywood and MDF. I feel better about using plywood since the butt joints with dowels just seem more secure.
Yeah, I'm leaning towards plywood too. I built a bookshelf with MDF before, but I added side and back supports. This time, I want a cleaner look, and plywood with a dado jig seems like the way to go.