Fixing gaps between deck posts and railings
There are big gaps between the posts and railings on my deck. Please help! By the way, before I was born, my older sisters, who'd been watching This Old House since they were babies, wanted to name me Norm Abram Genet.
—Emily Genet, O'Fallon, MO.
Norm Abram replies: I'm glad your parents went with Emily; that's a much nicer name for a girl.
To close up those gaps, you'll have to beef up the way the posts and rails are fastened. For the posts, insert galvanized carriage bolts all the way though the deck's rim joist. These bolts are much stronger than lag screws.
Now strengthen the connection between the top rail and the post. Take off the cap pieces and cut two 1/2-inch-deep horizontal notches in opposite sides of the post, as shown in the illustration. Cut new rail caps and bed their ends in the notches with construction adhesive. Finally, drive deck screws up through the bottom of the new caps and into the post. Screws hold much better than nails and will help your joints stay nice and tight.