How to Install Concrete Balustrades

Concrete balustrades require a solid base.

Setting the balustrades isn’t technically difficult, but lifting and carrying them is hard work. Although they’re meant to be decorative, local building codes might regulate the distance between the balustrades for safety purposes.

1. Snap a chalk line on the patio or concrete porch to represent the center line of the balustrade railing. If you’re using concrete newel posts, set them before installing the balustrades and use the same center line for both the newels and the balustrades.

2. Use two more chalk lines to represent the outside and inside edges of the balustrade bases. Concrete balustrades have large square bases that support the heavy columns. The distance of the second two lines from the first line is determined by figuring half the width of the balustrade base. For example, if the base is 6 inches wide, the inside and outside lines will be 3 inches from the center line.

3. Draw cross lines to indicate the sides of the balustrade bases. Spacing the balustrades depends upon local codes, the width of the balustrades, the distance between newel posts and the look you’re going for. For a professional appearance, the balustrades must be evenly spaced between the newel posts.

4. Dry-set the balustrades before you permanently attach them. Position each balustrade by following the guidelines and checking the measurements between each balustrade and between the end balustrades and the newel posts. If your measurements are even a little off, this is the time to find out and correct them.

5. Mix thinset mortar or another masonry adhesive with water in a 5-gallon plastic bucket. Follow the mixing directions on the package for the best results.

6. Set the two outside balustrades first by spreading a small amount of thinset onto the concrete base with a 1/4-inch notched trowel. Use just enough thinset to cover the base area completely. Pull the trowel firmly across the concrete to leave 1/4-inch ridges of thinset.

7. Position the balustrade by aligning the base with the lines. Work the base back and forth slightly to “seat” the balustrade into the thinset.

8. Check the sides of the balustrade with a carpenter’s level to ensure that it’s straight. If it’s slightly off, you can work the base back and forth a little more. Pressing down on the high side to displace the thinset should level the balustrade.

9. Set the second balustrade in the same method beside the next newel post if you're using newel posts. If you're setting concrete balustrades without newel posts, install them in sections no longer than 10 to 12 feet at a time to ensure that each section is straight and level before adding the next section.

10. Wipe any excess thinset off the concrete immediately after setting the two outside balustrades and wait for the thinset that holds the balustrades in place to harden before continuing.

11. Clamp a long straightedge on the outside top edges of the two balustrades. You can use a straight 2-by-4 or any other long straightedge that reaches between the two balustrades. Use C-clamps to tighten the straightedge to the balustrades. The straightedge will serve as a guide for installing the rest of the balustrades.

12. Set the remaining balustrades in the same manner by seating each one into the thinset base until it’s straight, plumb and lightly touches the straightedge. Check for level frequently as the thinset hardens. Once all of the balustrades are in place, you can install the handrail.

Tip

Building inspectors often carry a 4-inch ball to check the spaces between balustrades. If they can push the ball between and through the balustrades at any spot, the railing might not be in compliance. Because some concrete balustrades will leave a gap larger than 4 inches, even when the balustrade bases are butted tightly together, check with your local building authority before installing this type of baluster.