Deck handrail post wobble.

[acer66]

Hey,

Was called to take a look at a deck post that moves.

This is second story deck and it looks like they build a hollow 5x5 post out of 5/4” decking boards.

Post sits on top of the 5/4” decking.

The framing underneath the post is double 2x rim joist and a joist attached to the rim joist.

They used some structural, as far as I can tell, screws to toe screw the post through the decking into the framing.




Options I have come up with so far.

Remove post and use a 6x6 to create a solid 5x5 that runs down the full height of the rim joists and gets bolted into the rim joists.

Which requires to shorten the joist and a cross brace to the adjacent joists to box the post in to make it as sturdy as possible.

Then attach the joist to the cross brace that is secured to the post/rim joists to avoid doubling up the adjacent joists.

Which to me is the tricky part of this solution since I am not sure how sturdy that is.
Maybe double up the cross brace?

Could also just use the 6x6 as is but that is more work since I need to shorten the hand rail.
But I might have to do it because around here a 4x4 not notched is the minimum for a deck post.


Second option is to find a post bracket approved for this and add framing members brackets underneath that the bracket can be bolted into.
The simpson E-Z Retrofit Post Base is the closest I could find for that.



Third option would be to remove the hand rail and posts all together and bolt 4x4 posts onto the outside of the rim joists and get creative with the handrail.


Thoughts?


Thank you.

 

[karoc]

I watch YouTube year or two ago where deck builder had built a box around post. Example he ran say 2x6 in front of post from one joist to another, then put 2x6 on both sides of post. He use GRK multi screws to put all together. But this would require you to remove couple deck boards

 

[strutaeng]

Looks like that handrail post was just toe-nailed (toe-screwed) to the deck? SMH. If one of those posts rotates, chances are ALL of them will move with sufficient force. Please review the IRC for guardrail force requirements.

You got a sketch of what you have in mind? Notch the 6x6 and lap it down the side of the rim joist, is kinda what I understood, then got lost in your description?

Unless you use the Simpson MPBZ post base, all other post bases are considered as pinned, and will only transfer lateral and upward/downward forces, but not have rigidity enough to resist (much) rotation.

MPBZ™

The new patent-pending MPBZ is the first post base specifically designed to provide moment resistance for columns or posts and features an innovative overlapping sleeve design to resist rotation.

www.strongtie.com

C-C-2026-p088-089.pdf

ssttoolbox.widen.net

Of course, that guardrail force has to be resisted by something else on the deck framing. Assuming the posts are placed directly over a joist framing perpendicular to the edge? They make tension ties you install on joist to transfer the force into the joist.

Here's a lot of good information: https://www.strongtie.com/solutions/deckcenter

 

[Jackfre]

A floater. If I’m following correctly I think you should put in the new post through to the bottom depth of the joists. Thru-bolt to both sides of the lower post to the rim joists. Diagonal bracing of those would be advisable or they will be your next repair.

 

[rlitman]

...Remove post and use a 6x6 to create a solid 5x5 that runs down the full height of the rim joists and gets bolted into the rim joists.

Which requires to shorten the joist and a cross brace to the adjacent joists to box the post in to make it as sturdy as possible...

Looking at your decking running parallel to the railing, I would assume the rim joist is perpendicular to the floor joists. If so, attaching the post to the rim joist makes it relatively easy to push out on the railing and twist the rim joist, separating it from the floor joists at the top (railings have a LOT of leverage).

What I've done is use two bolts through the post. The lower is a lag bolt that holds the post into the rim joist. The upper is a piece of all-thread with a nyloc nut and washer that runs through the rim joist and pulls on a wall hold-down installed horizontally into the floor joist at a distance from the edge (like this, but sideways).


That railing will hold back anything you throw at it (which is good, because I have planters hanging off of it).

 

[acer66]

Looking at your decking running parallel to the railing, I would assume the rim joist is perpendicular to the floor joists. If so, attaching the post to the rim joist makes it relatively easy to push out on the railing and twist the rim joist, separating it from the floor joists at the top (railings have a LOT of leverage).

What I've done is use two bolts through the post. The lower is a lag bolt that holds the post into the rim joist. The upper is a piece of all-thread with a nyloc nut and washer that runs through the rim joist and pulls on a wall hold-down installed horizontally into the floor joist at a distance from the edge (like this, but sideways).


That railing will hold back anything you throw at it (which is good, because I have planters hanging off of it).

Yes, I have used those type of brackets on my last deck build.
But I already forgot about them, thank you for the reminder.

Looks like putting posts on the outside of the rim boards is the way to go and get creative with the handrail while doing so.

 

[firebirdparts]

Go underneath and shorten the joist.

 

[wssix99]

I have used these and love them! https://titanbp.com/pages/wood-post-anchor-kits/

I make sure some of the bolts hit the rim joist and the wide plate and extra screws make the whole thing solid. Center drilling the post for the bracket is a bit of a PITA and requires a special drill bit, but it pays off.

 

[acer66]

I have used these and love them! https://titanbp.com/pages/wood-post-anchor-kits/

I make sure some of the bolts hit the rim joist and the wide plate and extra screws make the whole thing solid. Center drilling the post for the bracket is a bit of a PITA and requires a special drill bit, but it pays off.

Nice, never have these before.

Need to read up how code compliant they are.

 

[yatg]

Looks like that handrail post was just toe-nailed (toe-screwed) to the deck? SMH. If one of those posts rotates, chances are ALL of them will move with sufficient force. Please review the IRC for guardrail force requirements.

You got a sketch of what you have in mind? Notch the 6x6 and lap it down the side of the rim joist, is kinda what I understood, then got lost in your description?

Unless you use the Simpson MPBZ post base, all other post bases are considered as pinned, and will only transfer lateral and upward/downward forces, but not have rigidity enough to resist (much) rotation.

MPBZ™

The new patent-pending MPBZ is the first post base specifically designed to provide moment resistance for columns or posts and features an innovative overlapping sleeve design to resist rotation.

www.strongtie.com

C-C-2026-p088-089.pdf

ssttoolbox.widen.net

Of course, that guardrail force has to be resisted by something else on the deck framing. Assuming the posts are placed directly over a joist framing perpendicular to the edge? They make tension ties you install on joist to transfer the force into the joist.

Here's a lot of good information: https://www.strongtie.com/solutions/deckcenter

 

[PoorUB]

When I built my deck I ran the posts down the outside of the rim joist and used carriage bolts. They are solid! Working out the corners kinfd of ****, but I just put two posts in each corner and a short block at the top to keep them together.

The other way I would do it would be to run the post down on the inside of the rim joist and through bolt it, or GRK screws and add more blocking.

Third choice would be a aluminum railing "kit" and lag the base of the posts to blocking under the deck surface.

 

[wssix99]

Nice, never have these before.

Need to read up how code compliant they are.

My inspectors were fine with these materials to be confident in the systems compliance with the performance-based requirements of our handrail code. https://titanbp.com/resources/engineering-reports-new/

 

[acer66]

Looks like that handrail post was just toe-nailed (toe-screwed) to the deck? SMH. If one of those posts rotates, chances are ALL of them will move with sufficient force. Please review the IRC for guardrail force requirements.

You got a sketch of what you have in mind? Notch the 6x6 and lap it down the side of the rim joist, is kinda what I understood, then got lost in your description?

Unless you use the Simpson MPBZ post base, all other post bases are considered as pinned, and will only transfer lateral and upward/downward forces, but not have rigidity enough to resist (much) rotation.

MPBZ™

The new patent-pending MPBZ is the first post base specifically designed to provide moment resistance for columns or posts and features an innovative overlapping sleeve design to resist rotation.

www.strongtie.com

C-C-2026-p088-089.pdf

ssttoolbox.widen.net

Of course, that guardrail force has to be resisted by something else on the deck framing. Assuming the posts are placed directly over a joist framing perpendicular to the edge? They make tension ties you install on joist to transfer the force into the joist.

Here's a lot of good information: https://www.strongtie.com/solutions/deckcenter

Yes you are right.
The existing post, all of them actually on that side, sit kinda center where the two rim joists and deck the joists meet.

Slow day in my noggin so excuse my very rudimental drawing.

 

[acer66]

When I built my deck I ran the posts down the outside of the rim joist and used carriage bolts. They are solid! Working out the corners kinfd of ****, but I just put two posts in each corner and a short block at the top to keep them together.

The other way I would do it would be to run the post down on the inside of the rim joist and through bolt it, or GRK screws and add more blocking.

That is how build the few decks I build.

I rather go the extra mile to make sure the posts are rock solid.

 

[acer66]

My inspectors were fine with these materials to be confident in the systems compliance with the performance-based requirements of our handrail code. https://titanbp.com/resources/engineering-reports-new/

Good to know and this might be the least costly option.

Guess we could just make the lower part of the hollow post solid with some wood and epoxy for the bracket screws.

Or maybe better use a 6x6 and shorten the handrails.

Sorry, thinking out loud here.

Adding blocking for those would be much easier since the deck is like 10-12’ above ground.

Thanks again for sharing.