Framing blocking (also called “backing”) is solid lumber installed inside wall or ceiling cavities to provide a nailing or fastening surface for future fixtures — handrails, grab bars, TV mounts, heavy cabinetry, and towel bars are common examples. Fire blocking serves a life-safety code function: interrupting fire spread through concealed cavities. Both types should be installed during the framing phase, before walls are closed in — retrofitting either is expensive and disruptive. RainFire Builders installs both as a standard part of every framing scope.