Deck Railing Calculator
Determine the quantity of balusters for your stairs and deck perimeter.
This calculator will tell you:
- How many balusters you’ll need
1. Total Linear Feet of Railing
2. Post Type
3. Total Posts
4. Baluster Type
5. Spacing Between Balusters
In order to be up to code, U.S. building codes mandate that balusters have no more than a 4-inch gap between them.
Your Deck Railing Calculator Results
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Results
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How Many Spindles Do I Need?
In order to determine how many spindles you’ll need, you should first know how much space should be between deck balusters. In order to comply with building regulations and codes, balusters must be spaced less than 4 inches apart. The test is called a “4-inch sphere test” - basically could a 4” wide ball fit between the balusters. If not, you should be compliant.
How Far Apart Should Spindles Be On a Deck Railing?
The general rule is that your railing must have three balusters per foot (every 12 inches), although you can place them closer together if you’d like. The length of your railing (in total linear feet) will play a factor in how many balusters you’ll need to be sure your deck and railing are compliant with safety standards. Use this deck railing and spindle calculator to help you find out how many balusters (or spindles) you’ll need for your project.
