For those of us who only use a tape measure occasionally, we may never have noticed the presence of black diamond marks. Let alone ask what the reason behind them is.
But if you are frequently doing handy work or improvements around your home you may have noticed them. So we’re going to take a look at the real reason behind those diamond shapes.
Features Of A Tape Measure
When most of us pick up a tape measure our primary objective is to measure a distance for cutting or fitting something into a space. Most of the time we just note the numbers on the tape measure and move on.
We typically don’t take much notice of the other features of a tape measure unless we are actively using them. But sometimes we are using them without even realizing it.
For example, have you noticed that the tape measure is curved? Have you ever wondered why? Well, it’s to maintain the rigidity of the tape measure when it is extended.
As this makes the measuring tape reasonably self-supporting, it allows you to take measurements without needing another person to hold the other end of the tape.
Speaking of needing another pair of hands, there’s another nifty little trick that a tape measure keeps up its sleeve.
The nail grab is a little slot on the end hook. You can use this if you are measuring a long flat surface and have no one to hold the other end of the tape.
Simply put a nail or screw into the surface and hook the end of the tape measure onto it.
But this is not the only hidden benefit of tape measures. Those mysterious little black diamonds are there for a reason too
Let’s take a look at them, what the mysterious black diamonds on the tape measure represent and what they are used for.
What Do The Black Diamond Shapes Mean?
You will find these black diamond shapes at the 19.2-inch mark on your tape measure and every 19.2 inches thereafter. This is to mark the center between studs in the walls of your home.
To understand this a bit better it is helpful to look again at your tape measure and find the 16-inch mark. It will most likely be surrounded by a red box or be in red digits.
This is because most domestic houses have 16 inch separation on studs, so every 16 inches on your tape should be a red box or digits. On most buildings this allows for six studs for every eight feet.
In between the 16 and 24 inch mark you will find the mysterious black diamond shape. By dividing an 8-foot length by five, which is the number of spaces between 6 studs, you will arrive at 19.2 inches on tape rule blades.
This is the center between each stud or support. Eight feet is the standard length of plywood used in construction, by the way.
Look further along the tape measure, and you will find the 24-inch mark as a black box with an arrow top and bottom. This denotes the spacing of studs in smaller buildings with less load bearing weight such as a garden shed.
Who Uses These Markings?
So who uses these diamond shaped markings? Well, anyone who is building a house, doing remodeling, or even just hanging up a picture can use them.
They can be used instead of a stud detector to determine the placement of drill holes in your wall. If you are confident that the studs in your home are spaced at 16 inches then you can be sure that the black diamond mark denotes a clear space behind your drywall.
Of course, you should still check for any pipe work or electrical cables in this area before drilling holes to hang shelves, or pictures.
Another use of the diamond markings on a tape measure employed by construction workers is the placement of trusses in a roof.
By spacing trusses at 19.2 inches it is possible to have five of them in an 8-foot length. This type of placement allows for more weight loads with less wood.
The first black diamond is at 19.2” on metal tape measures and after that black diamonds will appear at 38.4”, 57.6”, 76.8” and finally at 8 feet or 96”. This kind of precision would be difficult without these marks on the tape measure.
They can also be used for the placing of I-beams instead of regular floor joists and the diamond shapes on your tape measure are ideal for spacing them in new construction.
How Do These Diamond Shapes Help?
Getting the spacing of studs or trusses correct is vital when building a house or doing remodeling work, so these markings on a tape are extremely helpful.
As stud work is often load bearing it is important to get the correct number of supports into each 8 foot length. This is normally six per 8 foot length.
For non-loading bearing walls the studs can be fewer and more spaced out as they don't need to be so close together when there is no weight on them.
By using the diamond shapes on the tape measure you can space the studs out at 19.2 inches each and this will give you five studs per 8 foot length rather than the 6 you would need if they were spaced at 16 inches
The same markings can be used to space out I-beams as floor support rather than the traditional timber joists. As these are stronger they can be further apart than their lumber counterparts.
These diamond markings also help with the spacing of roof trusses at 19.2 inch intervals.
So they are helpful in marking and spacing in the construction of walls, floors and roofs.
Why Are They Important?
While such a small indicator on a measuring tape may seem trivial to the majority of people, these little marks can make all the difference to how your new home is built or remodeled.
Most construction materials such as timber and sheet material in the US come in 8 foot lengths therefore most measurements have to work with and around this standard size.
By marking the span of studs and floor joists on a tape measure so that they equate to the width of a whole sheet of plywood it’s possible to avoid cutting it. This then saves time and money.
Do All Tape Measures Have Black Diamond Shapes?
As helpful as the black diamond shapes are on your tape measure you may be wondering if all tape measures carry these markings.
Most of the retractable tape measures you would use in construction will have the diamond shapes on them.
They will also have the other markings such as red numbers at every 16 inches for typical stud spacing and the black boxes for 24 inch spaced studs.
Other measuring tapes such as fabric or ruler types of measuring tools will not typically have these markings on them as they are geared toward different uses.
In Conclusion
We hope this guide to the diamond shapes on your tape measure has been useful for you and that you’ll be able to make good use of it in the future.