[This is part of my How to Install Moldings series.]
If you are going to use a tall, single-piece baseboard like the one pictured above, then you need to know about warpage.
First of all, keep in mind that this is a high-quality poplar baseboard I picked up at a really good lumber yard, and not an inexpensive finger jointed pine product.
One, all wood moldings expand, contract and warp with changing conditions. Sometimes it’s because the material was not properly cured before sale, but most times it’s simply because that’s the nature of working with wood. There are more variables to deal with.
That’s one reason skilled, honest-to-goodness woodworkers are so very proud of their craft — as they should be — because working with wood takes more skill and experience than working with mdf.
And that’s exactly why I work with as much mdf as possible here on The Joy of Moldings. To not only keep projects affordable, but simpler as well.
One, you keep on cutting pieces of wood molding in the hope you get a straight enough piece to use. Then you hope and pray that they don’t warp after you install them.
Two, you can build up your baseboard using mdf as your fascia, and then top it off with a separate base cap.
I’m always in favor of option two.
MDF, being an engineered product, is consistent throughout and not inclined to warp.
Yes it’s more work to build up your baseboard from two or three pieces, but to me it’s always worth the effort.
Besides, we’re not concerned with production installation here; it’s just you, your miter saw and a quiet weekend working around the house.
Hope this helps. Good luck!