For every remodeling job that involves knocking down a wall, there's another that calls for putting one up. "If you're refinishing an attic or adding a closet or home office, you're going to need an extra wall or two," says This Old House general contractor Tom Silva. Building a simple partition wall - a stud wall that divides an interior space without bearing any load - is a perfect introduction to the basics of home construction. This project employs the same principles and components that are used in the construction of any frame house: 2x lumber spaced and nailed correctly, then set plumb. Think of it as Framing Carpentry 101. Even though all this work ends up buried behind drywall, shortcuts lead to trouble. Framing with good materials and smart techniques lay the groundwork for everything that follows: smooth walls, countertops that fit perfectly, and doors that swing without sticking.