Painting Closet Shelves

https://www.bobvila.com/articles/how-to-paint-mdf/

My pantry shelves are painted particle board. They used the same paint as on the walls and after 6 years the paint is holding up just fine. This material has little structural strength to hold weight placed on it. It sagged a lot. It will even sag over time with nothing on it.

My plan is to replace the shelves with plywood, but using dimensional lumber, like a 1x2 edgewise under it, will minimize sagging.

The mdf is a glued pressed board. I’ve always used an oil based product for primeing and painting them.

MDF is designed to be painted.... any interior primer and paint will work

I have painted mdf before..use a good primer...then thin coats of paint,or better..spray paint after primer so you don’t get it too wet. I would probably use an enamel or poly as top coat. How about contact or wallpaper instead?

I used gloss latex paint and "cut in" along the walls and corners then rolled the paint on. Latex takes a little longer to completely "harden" but it is easy to apply. That was 15 years ago and the only problem I have had was in my pantry where I placed a heavy object too soon after painting, and didn't move it around. If you can take the time to let it dry more thoroughly than I was able to wait you shouldn't have any problem. I am assuming you are using new MDF shelving. If you have older MDF you will most likely want to clean then sand if necessary before repainting. My shelving was five years old when we bought the house and I just painted over the old (but cleaned) paint.

The trouble with MDF is how hard it is to paint. With the right prep, you can paint it and it will hold up. Here's an excellent tutorial that explains all the steps: https://www.doityourself.com/stry/how-to-paint-particleboard-furniture

Mine are painted, have been in this house 17+ years. I use baskets and boxes too.