Painting all sides of a built-in

[Don Morris]

I just finished the build of a built-in that consists of plywood with MDF shelfs. It's to be painted to match a built-in done by someone else when we had the home renovated several years ago. It goes in a niche, thus the back side will never see the light of day, so my question is: I always paint all sides with primer first, but do you always paint all sides the same number of coats of a finish coat regardless if one side won't be seen? The "seen" side will probably take at least two coats of a semi gloss.

[Frederick Rowe]

but do you always paint all sides the same number of coats of a finish coat regardless if one side won't be seen?

No need to prime or paint the sides not seen.

You say you're going to paint, and for many people this means latex to match trim on the wall. A word of warning if the built in will have books and any objects which will have sliding contact with painted surface.

Latex paint is prone to blocking; sticking to objects left on them (books, objects d'art) no matter how long it is left to dry. Consider an alternative finish if that's the case. Good alternates are tinted WB lacquer, or Acrylic Enamel paint.

[Don Morris]

Yes, Acrylic Enamel, semi-gloss is what's going on. Thanks for the reply. Didn't think I needed to go through all that. I do paint/seal projects on all sides that are exposed. Heard of someone who only sealed (I think it was with a poly) the top of a table. That started to warp in no time at all. He was told to poly all sides, but went for the "easy button". I just don't like doing things if they aren't necessary.

[Scott Holmes]

The table top that warped was most likely a solid piece of wood not PLYWOOD. With the criscross of grain, ply is pretty stable.

No need to paint both sides.

[Don Morris]

You're right, the table wasn't ply. It was jointed hardwood. But I've never forgotten the point that it should have been covered on both sides. Plywood would have been another story. From what I remember, I was told there were actually several made for a restaurant. Costly mistake trying to either be cheap on finish, or maybe it was time, don't know. If it was time: "The hurrier I go, the behinder I get".