Securing A Post Outside Rim Joist Parallel To Joists
Here is a typical scenario - an outside rail post along an end joist.
Because the post is along the length of the joist and set back
about 18" or so from the corner and the next closest joist is parallel,
the entire joist and frame has to be reinforced to handle the moment of
This means blocking between the two parallel joists is crtical.
Check out the drawing to see how the blocking and joist connectors
are set up to try to absorb that force. Note that here the post is
attached on the outside of the rim joist but with a simple change it
could be moved inside the framing.
Click Image For Larger View
Required Hardware And Cost
The blocking between the joists prevents the outside joist from
twisting when the outside rail post is under load. But this also means
the railing posts are outside the edge of the deck and so would the
railing sections in most cases.
Building deck railing this way works but it does not give you are
really finished appearance. If the deck boards to overhang the rim
joist, you will have to notch each deck board around each post.
Important:Remember that to
have equal resistance to an outward and inward force along the railing
you will need at least three connectors OR a smaller blocking piece
scabbed along the joist block and butting up against the bottom part of
But there are simpler ways to install a strong long lasting deck railing post without all the hardware, reduced concern for rotting that looks much better than an outside rail post.
If you fall into this gropu, there are railing solutions for decks available to get you a high quality and beautiful looking railing.
What you may wish to consider is to build deck railing
with posts that are connected to the deck boards by a low profile
surface mount anchor.
Take for example this low profile internal wood railing post anchor shown here.
At less than twenty bucks, it can be
used in code compliant residential rail applications when installed
according to the manufacuturer's engineering guidelines.
A Simple And Cost Effective Option
This is an easy way to build new wood deck railings, replacing rotted
railing posts, or as support posts for pergolas, gazebos, decks, etc.
Then watch this video of a surface mount wood post anchor that has been tested for use with wood deck railings and costs less than $20 with all the hardware you will ever need and it covers all the possible situations described above.
So there you have it.
A thorough explanation of building traditional wood railing for decks and alternative solutions for great looking deck railing. You decide which is right for your specific project.