New woodworker seeks advice for bathroom vanity project

April 20, 2018 7:16 AM

I'm a relatively new hobbyist woodworker. I've successfully made coffee tables, end tables, and bookshelves. Now I'm ready to tackle a cabinet project, and the first thing my house needs is a bathroom vanity. I'm looking for advice; specific questions inside.

I feel relatively comfortable with the general casework process, but I have a number of questions about bathroom furniture.

* The vanity will be painted. Do I need to use some sort of finish on top of the paint in order to protect the vanity from moisture, or is paint good enough?

* What wood should I use? I was planning on 3/4" plywood with poplar for the face frame and drawer fronts. Is MDF or another cheaper composite an option, or is that a bad choice for moisture-rich environments like bathrooms?

* What resources are there that show standard dimensions for vanity sizes (height, width of sections, drawer spacing)?

I'm also open to general advice about this project, so please share your experiences!

posted by philosophygeek to Home & Garden (10 answers total)

The vanity will be painted. Do I need to use some sort of finish on top of the paint in order to protect the vanity from moisture, or is paint good enough?

A good latex paint is fine, however you may need a primer specific to what you construct your vanity of.

What wood should I use? I was planning on 3/4" plywood with poplar for the face frame and drawer fronts. Is MDF or another cheaper composite an option, or is that a bad choice for moisture-rich environments like bathrooms?

MDF, generally, has variability in its construction due to things like fiber size being inconsistent during manufacture. What that means is - durability-wise, if moisture gets in MDF can degrade really, really quickly. Some of this can be mitigated by staying on top of maintaining it but in general, MDF is cheap for a reason. That's not to say not to use it but that it's not going to stand up anything like a solid wood cabinet will, so you'll have to determine where you land on the cost vs. durability spectrum today.

What resources are there that show standard dimensions for vanity sizes (height, width of sections, drawer spacing)?

Wood Magazine has a lot of good, free plans that can get you started on some standards, however one of the beauties of custom-made cabinetry is - you can customize it to what you need and what you have available in your bathroom. 31-32 inches is often a standard height for a bathroom cabinet, however much of what you build will depend on whether you have an inset sink or one of the cabinet-top bowl ones that are popular right now. Depth can be dependent on what your surrounding spaces provide (i.e., where doorways are) but in the range of 24 inches is pretty normal. Width...depends on how many sinks there are, what their dimensions are, and what needs you have for counter space.
posted by notorious medium at 7:38 AM on April 20, 2018

I have painted vanities in my bathroom. I did not seal the paint and there's been no adverse effects on the finish, however, I do have Corian tops on my vanities, so there is no direct splashing of water onto the paint. If your vanity top will be painted wood, I would definitely put a sealer on that.
posted by sarajane at 7:38 AM on April 20, 2018

I am currently planning a similar thing! Are you talking about painting only the vertical surfaces, or also the top of the vanity? I think you'd probably be fine with just a decent wood primer + paint on the vertical surfaces, but I personally would use a marine grade poly so I wouldn't have to worry about it. I would definitely use poly if there's going to be a flat wooden surface on the top of the vanity. Does your bathroom stay damp and grow mold or is it generally fine?

Most of the commercial units available seem to be mdf, but I wouldn't. MDF and water just don't mix, it puffs up and wears terribly. If you're going to all the effort of building it, I think you'll regret cheaping out and getting mdf instead of plywood in the long run.
posted by stillnocturnal at 7:43 AM on April 20, 2018

I used MDF in a place that is occasionally exposed to moisture. It provides such a beautifully smooth surface for painting, and I thought a good quality paint would protect it. I was wrong :-(
posted by kate4914 at 7:50 AM on April 20, 2018

MDF will swell if exposed to water, period. You may get away with it for a while, but eventually it will get scratched, you won't notice, and then it's done for good. Plywood is a much better option.
posted by wierdo at 7:58 AM on April 20, 2018

Response by poster: Adding a couple of details:

This will be a 72" long, double sink vanity. I'm looking at building the carcass and drawers, but leaving the top to a professional. The top will likely be a laminate countertop. We're looking at standard inset sinks rather than bowls on top or undermounted sinks.
posted by philosophygeek at 8:10 AM on April 20, 2018

I believe that many cabinets built with engineered panels, like mdf, are coated with some kind of resin product that is impervious to water vapor. If it doesn't break the budget, you could look at MDO which is used for exterior signs, among other things.
posted by SemiSalt at 8:41 AM on April 20, 2018

I built a painted bathroom cabinet 12 years ago. I used birch-faced plywood and latex paint (Benjamin Moore Regal latex) and it's still in extremely good condition. I would not use MDF in a bathroom because if the moisture barrier of the paint is breached and the MDF gets wet, it will swell and bubble and it won't really be fixable. I would not get hung up on standard dimensions; it's a lot of fun to design the cabinet to fit your personal needs. Mine is nothing like any bathroom cabinet I've ever seen and it also by far has the most usable storage per square inch of any I've ever seen, because it was made to hold MY stuff.
posted by HotToddy at 8:54 AM on April 20, 2018

Side-remark: regardless of the design or materials chosen, take care to seal the ever loving crap out of everything, everywhere. Even underneath. Bathrooms mean humidity, not just drips.
posted by aramaic at 12:11 PM on April 20, 2018

I built a cabinet (here and here) that fit into a disused dining nook in our kitchen. (Eventually we added a hunk of marble to the top.) I used this book for design and construction ideas and standard dimensions.

I think a general cabinet-making book from Taunton Press might help answer some of your bathroom vanity-specific questions (planning for plumbing, protecting against water damage, etc), such as this one.

Since you're an active hobbyist, I would also suggest a subscription to FineWoodworking's website, which grants access to decades of plans and howtos covering every project imaginable.
posted by notyou at 1:49 PM on April 20, 2018 [1 favorite]