Definition
A trimmer joist, also called a trimming joist, is a structural component in framing a floor or roof. It's a beam that supports the end of a header joist, which frames an opening for stairs, chimneys, or skylights. Essentially, it's a reinforcing joist that runs parallel to the regular joists. It provides extra support around openings to distribute weight evenly. Think of it like a bodyguard for the header joist. 💪