Bolting Wood Beams Together

When securing 2 or more dimensional wood boards together to form a beam you will need to use the proper number and size nails to create a solid member.

Bolting wood beams together.

T i ill i l d ti d itopics will include connection design philosophy and behavior an overview of 2015 nds provisions related to bolt design including appendix e for. A 2x10 beam should use a minimum of 4 3 nails fastened in a vertical pattern from both sides of the beam every 16 on center. Connecting wood beams with through bolts is a safe and easy way to secure two wooden support beams together. To solve this problem insert a few finishing nails in the hole beside the bolt before hammering the bolt into place.

An example of a regular bolting pattern might be 1 2 inch diameter or 5 8 inch diameter bolts spaced 16 inches on center. This course will feature a bolt design example utilizing awc s 2015 national design specification nds for wdc t tiwood construction. Bolts must be closer than seven times the diameter or 80mm from the joist end and four times the diameter from the top and bottom. While code typically allows 3 8 inch diameter bolts for fastening braces to posts beams or joists i use 1 2 inch diameter bolts instead.

To meet this requirement i bolt 2x4s to the posts approximately 2 feet below the bottom of the joists at a 45 degree angle to the beam and joists. Be on the safe side when in doubt and use extra nails. Stagger the bolts and make sure the bolts are placed a minimum of 2 1 2 inches from the edge of the beam. When joining pieces of wood together using a carriage bolt the square head on the bolt can become stripped in the hole making them hard to tighten.

The first method is an empirical method which is purely based on what has worked well in the past. The nails will fill the gaps between the hole and bolt to keep it from spinning.