Simple window trim suits many architectural styles spanning hundreds of years. Combined with horizontal wall cladding or bead board paneling with plaster above. Suitable for farmhouse style house, servants quarters or attic in more formal house.
Most of the T&G you'll find at home centers and lumberyards is 1x6 or 1x8 spruce. But other wood options and sizes can be special-ordered. Some boards are rough on one face and smooth on the other. Others, like the 1x8 boards used here, have a groove down the middle of one face to give the impression of more, narrower boards. Most stores carry 1x4 beaded ceiling board as well. These tips apply to any of the styles.
Installing tongue-and-groove (aka T&G) boards is a fast, inexpensive way to panel any ceiling or wall. You can install T&G over bare framing, drywall or plaster, so it's a great cover-up for an ugly ceiling.