Final answer:
The first course of horizontal lumber placed on top of and attached to the foundation wall is known as the sill plate.
Step-by-step explanation:
The first course of horizontal lumber placed on top of and attached to the foundation wall is known as the sill plate. The sill plate acts as a connector between the foundation and the framing of the walls of a building. It provides a stable base for the walls and transfers the loads from the walls to the foundation.In house construction, this is an important component as it serves as the interface between the foundation and the wooden structure of the house. It is usually made from a durable, pressure-treated wood that is resistant to decay and insects, due to its proximity to the ground.
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