People gobsmacked at real meaning of ‘diamonds’ on tape measure

Ever glanced at a tape measure and been puzzled by those mysterious black diamonds?

You’re not the only one scratching your head – it’s a common query that has many people turning to X, asking: “What are the black diamonds on a tape measure for?” The same question pops up on Reddit, where curious minds seek answers. Well, the mystery is about to be unravelled.

These black diamonds aren’t just for show; they serve a practical purpose, especially for professionals who rely on precision. They’re crucial for ensuring tasks are completed with efficiency.

Known as joist marks, these diamonds indicate the standard spacing between each joist centre, which is vital in construction work.

A user on Reddit shed light on their purpose: “The black diamond on a tape measure is a symbol that represents the centre area between studs in a home or building. It is placed between the 16 and 24-inch markings and is used to distinguish a measurement commonly used in building a chimney of concrete blocks.”

They further clarified: “The symbol will always be set at the 19.2-inch mark, and after that, black diamonds appear at 38.4, 57.6, 76.8, and 96 inches or 8 feet.”

According to How To Build It: “The 19.2 inches allows for a break at 8 feet to accommodate full sheets of concrete. While the black diamond spacing is nearly as weight-capable as 16-inch centres, building codes may not allow it in all situations,” So there you have it – those little diamonds are more than meets the eye, playing a significant role in the world of construction.

Another individual chimed in with a practical insight: “It divides an 8′ piece of plywood into five even sections. Some will say it’s for engineered beams, or some will say it’s a layout mark for 2×6 studs, but its all-encompassing function is to lay out members 5 to a sheet. 16″ gets you 6, 24” gets you 4, and the 19. Whatever gets you 5.

“The diamond is just there to make it easy since 96/5 doesn’t come out to a nice tape-measureable fraction. I’ve seen it used for wood beams as well as wall studs, and also solid lumber joists and rafters.”

These diamond markers have long been a cornerstone in the realms of lumber and construction, providing essential guidance for professionals to maintain uniformity and adhere to building codes.

Though they may not be part of your everyday toolkit, these diamonds on your tape measure can serve various purposes, from hanging home decorations to precision drilling.