How to Attach Two Beams Together

Measure and mark one beam in the location where the second beam will be attached: Position the end of the second beam at the correct angle (usually 90-degrees) to the side of the first beam, making sure that the tops of each beam are flush with each other. Run a pencil against both sides of the second beam's end so that it marks along the side of the first beam. This will produce two lines on the side of the first beam, that are parallel with each other).

Toenail the top of the second beam to the first beam. That is, hammer a galvanized 16d 3 1/2-inch nail at a 45-degree angle through the top edge of the second beam near its end and into the side of the first beam. This will hold the two beams together and free both your hands to install the hanger.

Slip the joist hanger around the second beam from underneath, pushing it up into position and resting it against both beams where they join together. Make sure there are no gaps between the hanger and beams, either on the sides or where the hanger wraps around the bottom of the second beam.

Knock the speed prongs near the top of the hanger into the first beam. This will hold the hanger in place. Hammer joist nails through the holes in the hanger into the first beam. Then hammer joist nails through the holes in the hanger into the second beam.