How to Mount a Box Newel on a Post

Measure the inside (hollow) dimensions of your box newel. Most box newels have a square hollow box design. Cut a mounting block 3 inches tall by your dimensions.

Measure the newel post to the correct height you need for your stairway application. Cut off the bottom of the newel post at the height you need.

Drill two offset holes at least 1 1/2 inches apart through your mounting block post from the top to the bottom. These should be sized to fit your lag bolts.

Mark the center line of your post on the stair tread or floor where you wish to mount the newel post. Position your block centered over the mark, and drill through the tread or floor if you are using a toggle bolt. If you are using a lag bolt with a screw end, you will not need to drill through the floor.

Apply construction adhesive to the bottom of the wood block. Position the block over the marks or holes. Bolt the block to the stair tread or floor using a lag bolt and washer or a lag toggle with washer. Tighten it with a wrench.

Slide the newel post over the wood block and attach it with two wood screws centered through the back side 1/2 to 1 inch above the stair tread. The screws should be 1 inch apart. Countersink the screws and use small wood plugs to hide the screw holes. If your newel is a hardwood, predrill the screw holes for a clean fit.