If you’re ready to learn carpentry, you’ll quickly find that the term 16 on center will be applicable (at least in part) to just about anything you do building/renovation-wise. In this tutorial I will explain what it means, why it’s so important, and HOW to apply it easily with any project.
Whether you’re an aspiring future carpenter, preparing for a DIY project at home or just plain curious, this article will tell you everything you need to know.
“16 on center” is a framing term that typically refers to the spacing of wall studs.
It could also refer to the spacing of floor joists, rafters, etc, but for the sake of simplicity we’ll continue using wall framing as an example.
To be specific, 16 inches on center means that the center of any wall stud should always land on some ‘increment’ of 16 inches from the end of the wall.
For example, the distance from the end of the wall to the center of the first stud should be 16 inches, the distance to the center of the second stud should be 32 inches (16 + 16 = 32), then 48 (32 + 16 = 48) etc. This 16″ spacing serves a couple distinct purposes in construction which I’ll explain below.
Why is this 16 inch stud spacing so important?
The first and most obvious reason for 16 inch stud spacing is that this is what most building codes call for in terms of structural integrity. It is worth noting however, that some applications might call for something different.
For example if you intend to install heavy tile flooring and furniture or build a large stone fireplace, 12 inch spacing might be more appropriate than the standard 16 for any load-bearing stud walls or floor joists that will be supporting this additional weight.
The second reason most framing is done based upon sixteen on center layouts, is that most construction materials are manufactured at 8ft and 16ft lengths to maximize production and minimize waste. Full 8ft or 16ft pieces (whatever it may be) should always land on the center of a stud, allowing the next piece to butt up against it, and for both pieces to be nailed/screwed to the same stud.
So even if you’re building a wall that was completely non-load bearing, you should still layout your wall studs at 16 inches on center. This way when it comes time to hang drywall or nail up trim, you’ll always have a stud right where you need it.
How to Layout your Framing to 16 on Center.
Now that the background is out of the way, let’s look at HOW you actually go about applying this information in your framing. Again we’ll use a stud wall as an example here, but this can be applied to anything else such as floor joists.
- Step 1 - Hook your tape measure on the far end of either the top or bottom plate to begin marking layout.You will eventually need to mark both the top AND bottom plate. (The "plates" are the horizontal 2x4 studs at the top and bottom of your wall which span the entire length)
- Step 2 - Using your speed square and a pencil, mark a line across the plate at 15 1/4 inches and place an X on the RIGHT side of that mark.
The purpose of the X is so you know which side of the line to nail your stud, the stud is always nailed ON the X.This marks the location of the first stud. The LEFT side of the board should be flush with the line you just made and cover the X.The 15 1/4 measurement will ensure the CENTER of the stud lands exactly at 16 inches. - Step 3 - Hammer a temporary nail or screw into the 15 1/4 mark you made in step 2.
You'll use this nail to hook your tape and make all of your 16 inch marks. This is a handy trick of the trade, so you're welcome in advance. - Step 4 - Hook your tape measure onto the nail and make a mark every 16 inches from that.
Just like step 2, use your speed square to make a nice line at each mark, and draw the X on the RIGHT side of each one. Do this for the entire length of the wall, making a line and an X at every 16 inch increment - 16, 32, 48, 64, 80, 96 etc. - Step 5 - Nail your wall studs. That's it!
Once both your top and bottom plate have been marked, just put your studs on the X’s and that’s all there is to it!
Follow these simple steps and your wall stud spacing will now be a perfect 16 on center every time.
Here’s a good video on the topic. It’s a slightly different method than what I’ve explained above (minus the nail trick), but the end result is still the same and he mentions some tips you might find useful.