How can I join rails end-to-end to create a tight, water-resistant seam?

An end-to-end handrail joint works much like a bed-frame joint. The nut on the hanger bolt pulls the butt joint tight.


For a ramp leading to the entrance of my shop, I need a handrail more than 20' long. But the handrail stock at my home center measures only 8' long. How can I join the rails end-to-end to create a tight, water-resistant seam?
—Ralph Kimbrel, Poquoson, Va.


The humble hanger bolt comes to your rescue, Ralph. These headless fasteners have one end threaded like a screw, the other like a bolt. You'll find them in various sizes at the home center or hardware store, and for exterior use, they come in stainless steel or galvanized versions.

To join rails end to end, square cut your rails, making certain the joints land on or near one of the rail's supports. Mark the center of the mating ends and drill a pilot hole sized for the screw end of the hanger bolt in one of the handrail ends. Use two nuts on the bolt threads to drive the screw into the pilot hole. On the mating rail end, drill a hole for the bolt end sized about 18 " larger than the bolt, as shown above. Then use a 1" spade or Forstner bit to bore an access hole in the bottom of the rail that intersects the bolt hole you just drilled.

Insert the protruding hangar bolt into the bolt hole. Add a washer and thread the nut through the access hole. Finger-tighten the nut and line up the rail ends. Then tighten the nut with a small wrench.

Finally, no exterior joint will be completely watertight, but you can increase the handrail's chances with a couple coats of exterior-grade paint.