Installing Wooden Balusters

For quite a number of years 3/4" dowels have been used to fasten balusters to stair treads, balconies and landings. Yet there are other alternatives that, in my opinion, make for a better method of baluster installation.

I installed a few stairways when I was in the home building and remodeling business and was accustomed to drilling 3/4" holes for the typical baluster dowel.

On one particular job, however, I contracted a stair company to take care of the whole stair project. They used a doubled threaded screw to attach the balusters to the tread. That was the last time I ever used 3/4" dowels on one of my stair projects.

As you can see from the image above the baluster screws right into the tread making the installation easier but, in my opinion, making a more secure joint. The most important thing to remember is to screw the double threaded screw into the tread first since treads are typically a harder wood than the wooden baluster. Otherwise the screw will probably "strip" the pilot hole in the baluster.

You should use the 5/16" double threaded screws. The pilot holes should be 9/32". There are centering devices for drilling a centered hole in the bottom of the baluster as well a double threaded dowel drivers that attach to a portable drill. If you use it you probably won't go back to the old method.

Another method (one I have not tried but probably superior to the method above) is the "tee" nut. In this method a pilot hole is drilled into the tread, a "tee" nut is inserted with a special driver device made especially for this system. The screw that the baluster receives has both a screw thread and a machine thread. In this case the baluster should receive the hardware first and then the screw thread is screwd into the "Tee" nut.