What is a sill plate?

A sill plate is the horizontal member that rests on top of the foundation of a building or a structure. It serves as the base for the wall framing, and it is usually made of wood, concrete, or steel. The sill plate provides a level surface for the wall framing and helps to distribute the weight of the structure evenly to the foundation. It also helps to prevent moisture from entering the structure by creating a barrier between the foundation and the framing. Sill plates can be anchored to the foundation using bolts, screws, or other fasteners to ensure the stability and safety of the structure. Insulation can be placed between the sill plate and the foundation to increase energy efficiency and reduce heating/cooling costs.