In a construction drawing, what does the notation "8d" refer to?

The notation "8d" in construction drawings refers to an eight-penny nail, which is commonly used in framing applications. The term "penny" (denoted with the letter 'd') originates from historical practices related to the pricing of nails. An eight-penny nail typically has a length of 2.5 inches and is used for a variety of framing tasks because of its strength and appropriate size for connecting wood members.

In the context of construction, nails are categorized by their penny size, which informs builders about the length and suitable applications for the nails. Understanding this terminology is crucial for interpreting drawings and ensuring that the correct fasteners are used in construction projects. The other options refer to measurements or timelines that do not align with the specific meaning of the "8d" notation in construction terminology.