CSLB General Building (B)Framing and CarpentryEasy
A framer is instructed by the job superintendent to use '16d' common nails for wall plate connections. What does the number '16' indicate about the nail?
- AThe wire gauge (diameter) of the nail shank
- BThe number of nails contained in one pound
- CThe head diameter measured in sixteenths of an inch
- DThe penny weight, which classifies the nail's length
Show answer & explanationAnswer & explanation
Correct answer: D. The penny weight, which classifies the nail's length
The 'd' symbol stands for penny weight, an old English sizing system that correlates to nail length. A 16d common nail is 3-1/2 inches long, which is why it is commonly specified for framing connections such as double top plates.
Why the other options are wrong
- A. Wire gauge is a separate specification, not indicated by the penny weight number.
- B. Nails per pound varies with nail size but is not what the '16d' designation directly states.
- C. Head diameter is a separate dimension not described by the penny weight number.
Penny Weight (d)
A traditional nail sizing system where the letter 'd' follows a number to indicate nail length, originating from historical English pricing.
- 8d nail = 2-1/2 inches long
- 16d nail = 3-1/2 inches long
- Higher penny weight = longer nail
Memory trick: 'd' is for 'distance'—the bigger the number, the longer the nail.