Tips for Spacing Staircase Balusters

staircase with balusters

If you are installing stairs inside a building, one key to passing a building inspection is by correctly spacing your balusters. So what are staircase balusters? They are spindles that make up the edge of a staircase, the balustrade, and keep people from falling. Correctly spacing these balusters is not only crucial for passing an inspection, but also a significant factor in maintaining the safety of anyone who may use your stairs.

Step 1 - Know Your Building Codes

Considering that your main goal is for your project to pass a building inspection, research your building codes. The specifics vary depending on your location, so study the details carefully. Even if you have experience with constructing stairs and consider a gap of 4 inches between balusters to be the standard, a code specific to the area could state that 3.5 inches is the largest space allowed. This minor detail could result in a failed inspection.

Step 2 - Measure the Staircase

Before you even begin to plan out the placement of the staircase balusters, start by carefully measuring the length of the staircase itself. Take your measurement beginning from the post at the top of the stairs and proceed all the way to the post at the bottom of the stairs. This distance is the length of your balustrade and is thus the space you will need to cover when placing the balusters.

Step 3 - Measure the Balusters

Now you can consider the all-important balusters. Use your measuring tool to find the width of one single baluster. It’s a good idea to repeat this step with more than one individual spindle, as their widths may vary slightly from piece to piece. Once you’ve determined the appropriate width of a baluster, add that number to the length of the staircase that you found above.

Step 4 - Calculate How Many Balusters You Need

Next, you can begin to calculate just how many balusters you’ll need. Recall the width between spindles that is allowed by your building code. Add this number to the width of an individual spindle you calculated in the previous step. Then, divide that sum by the total length of your staircase. After you divide, it’s possible you won’t have a nice whole number. If you do wind up with a fraction or decimal, simply round the answer down to the nearest whole figure.

Step 5 - Space the Balusters Out

The building code dictates the limits of how far apart balusters can be on a staircase. But, even within the confines of that code, how far apart should you space the balusters for your specific set of stairs? You can answer that question by multiplying the total number of balusters that you just rounded to with the width of any one baluster. Take the number you get after that and then subtract it from the total staircase length that you found when you first began measuring. When you have the difference, divide it by the total number of balusters that you found in the previous section.

Step 6 - Evaluate Numbers and Figures

After this much math, your final number may not be pretty or convenient to work with in terms of real-world measurements. If that’s the case, and your space ends up being too small, feel free to remove a spindle from your overall amount while continuing to mind your building code. Just stay aware of those regulations about the maximum space between each part of the balustrade.