Have you ever wondered ” how far apart are studs” and been confused when you heard or read “16 on center” or “16 oc”? Today we’re taking it back to the basics and explaining exactly what on center (oc) means in the construction and home renovation world and how far apart the studs are in your wall.
Framing a wall is one of the most basic and initial steps to a structure. However, when done incorrectly it is a mistake that ruins the rest of the build.
One important aspect of any wall is the specific stud spacing. This can make or break your structure.
You may have heard framing is done “16 oc” or “16 on center”. No need to get confused with this lingo! We’re going to break it down for you in this article all about stud spacing in construction.
What does 16 on center mean?
16 on center or 16 oc simply means you place the center of the stud every 16 inches.
16-inch stud spacing is the industry standard for residential wall framing. The reason for this is structural but also because materials are made in 8ft and 16ft lengths.
For example, drywall is attached directly to the studs and comes in 8-foot lengths. When you place your studs 16 inches on center the ends of the drywall butt up against each other over the stud, giving you a convenient place to screw the drywall into place.
To detail the 16 on center concept further, here’s a handy little diagram.
Stud spacing FAQs
On center just means that the center of the stud should be placed every 16 inches when framing out the wall. Rather than measuring the distance between the edges of the studs, you measure the distance from the center of one stud to the other center of another stud.
Studs should be placed 16 inches apart on center. There are certain exceptions to this rule but this is the standard.
Stud spacing in older homes is similar to that of newer homes. Studs should still be 16 inches apart on center in old houses.
Typically this is done in outbuildings or other structures that aren’t homes. There are a lot of restrictions using 2×4 studs spaced at 24 inches on center so typically we won’t see this spacing often for residential construction.
You may be heard that when you hang something up on a wall that you need to make sure you’re attaching it to a stud in the wall. This is definitely best practice when it comes to anchoring items to a wall, hanging heavy pictures, and floating shelves.
Anytime you are hanging a picture up on a wall, you should first find a stud in the wall to make it more secure.
A quick and easy way to find a stud is with a stud finder, but they can be unreliable from time to time.
The best way to find a stud in a wall is to measure 16″ from the corner of the wall you are trying to find the stud on. Follow up with a stud finder to confirm before drilling a hole or making a nail hole. This will give you a really good chance to find the stud.
Using just a nail I would hang no more than 5-10 lbs. There are many different fasteners and anchors specifically designed to help hold far more weight when a stud is unavailable.
Studs are always 1.5 inches wide. Their depth can be 3.5, 5.5, or even 7.5 inches depending on the wall.
Wall studs are made with “2 by” lumber, meaning either a 2×4 (most common), 2×6, or even in some rare cases, 2×8. However, that doesn’t mean that the wood is actually 2 inches wide. Nominal vs dimensional lumber can be confusing, learn more about confusing lumber dimensions here.
How do you measure 16 on center when framing a wall?
Fun fact, tape measures highlight every 16 inches red to help builders and DIYers put this standard into practice.
Before you start building a wall, be sure to get a tape measure and start marking up your bottom and top plates. The best way to do this is to mark the plate every 16 inches. This will be the center point on the studs.
Now you can go back and measure 3/4″ on each side of the 16″ marks because the studs are 1.5″ wide. These marks represent where the studs will go to space them 16 on center.
We usually mark in between the lines with an X to represent where the studs will go.
Further reading – If you want to learn more about the process of how to build a wall, check out this full tutorial. There’s a lot more to it than just figuring out stud spacing! If you need to add a door to your wall, read all about framing a door here.
If you go further in your renovation and woodworking journey you may hear of other applications of on-center. In certain situations, studs can be spaced as close as 12 inches on center and as far apart as 24 inches on center. But when it comes to the walls in your home, you can count on the stud space to be 16 inches on center.
Do you have any more questions about stud spacing and the on center definition?
Let us know in the comments below!