What is the best way to tie together vertically two pressure treated 6x6's?

Question

I'm using 12 foot pt 6x6's as the vertical supports for a footbridge over a stream and because of the slope of the ground, one of the supports has come up about 3 feet short of requirement.

The 6x6 in question fully supports the deck portion of the bridge, but only extends about 30 inches above the deck level. I want to extend the 6x6 by another 48 inches to that it will in turn support an angled roof, kind of covered bridge style.

Backing out the 6x6 at this point would be a real pain in the butt. Could I use a dowel or large screw embeded in the existing 6x6 and then screw into the new 6x6?

Thanks for any idea's.

Answer 1

I would carefully cut a lap joint for the two posts to be bolted together....cut out a section of wood halfway through each post and about 6 inches long, then drill 3 or 4 holes through each joint to use bolts or lag srews to join them together. Recess the holes for the bolt heads and nuts to make it less obvious and maybe putty up the holes as well. Maybe use some construction adhesive between the two joints to help glue everything together. It should make for a very strong joint.

Answer 2

1

Answer 3

paul h has the basics.........cut a lap joint, or as we boat carpenters say a scarph....I'd make it at least a foot if not 18 inches......once the wood is perfectly dry use either Elmers yellow glue, 3M 5200 adhesive caulk or best of all epoxy.....and you MUST use through bolts not lags..think what will happen if this comes loose!.....3 bolts, at least 3/8ths and 1/2 would be better....

and you CAN NOT drill a dowel down the middle of the short piece and stick the extension on top.....it will for sure fail in a wind or snow load situation and then gravity takes over,,,,followed by the cops and the lawyers!

Answer 4

WHY NOT DRILL HOLES THROUGH BOTH 6X6 AND CONNECT THEM WITH A COUPLE OF REALLY BIG BOLTS...