How hard to write, on this deck. Built up vertical posts

I’m waffling a bit on how hard to write up this deck element:

Aside from the twisting lumber, it appears to be built up from 2x lumber. So there’s no central post, just a bunch of 2x’s nailed together into this configuration. Part of my concern is water will get between all these (unpainted) posts and rot sort of inside out.

It’s a fairly new deck, and seemed solid enough.

Detail photos at

Your thoughts?

What’s the difference between a built-up post, and a solid post with large checks?
Not a damned thing!

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fairly new deck? You sure about that?
A bunch of 2x’s nailed together is called a build-up column or build-up post as Jeffrey mentioned.
Poorly assembled.
I bet there’s a lot of building defects there…

From MN, that center post looks like a 4 x 4 nominal dimension. The only issue with that is what concentration of treatment (0.04 vs 0.06) and the height of the column. The 2 x 4’s on the side provide much better resistance to the beam twisting, vs nothing at all except maybe metal hardware connectors.

I’d note the separation and for a solution (if you do that in your reports) recommend adding galvanized lag screws or carriage bolts.

This is incorrect, or at least conditional. If the built up elements are not connected to each other with a proper nailing schedule, they can warp independently of each other and one may take all the actual load.

A single 4x6 will rot from the outside, and can be painted and inspected from the outside. An assemblage of 2x lumber lets water run down between them, and cannot be painted or inspected. It can literally rot from the inside out. A 4x6 post can rot from the ends in, but that’s completely different.


What the American Wood Council has to say on this is:

Built-up Columns with Mechanical Fastenings
Arrangement of laminations joined by nails, bolts or other mechanical fastenings into a built-up column assembly will not make a column fully equal in strength to a one-piece member of comparable material and dimensions. The following provisions apply to nailed or bolted built-up columns with 2 to 5 laminations… The column stability factor, C, shall be modified (multiplied) by 0.60 for built-up columns nailed in accordance with NDS section 15.3.3 or by 0.75 for built-up columns bolted in accordance with NDS section 15.3.4
(Source Wood Structural Design Data - American Wood Council AWC Wood Structural Design Data WSDD, 1992 Revision.)

So @jjonas if you enjoy insulting and belittling on this forum, I suppose that’s your role. If not then please make a deposit in this bin:

And let others weigh in on the differences between built up and single columns in this application, and what the downsides may be. The deck was modern built – I was told the date but forgot – and clearly without permits. It is however solid and not immediately unsound.

It’s clear to me that some through lag bolts and a flashing would greatly improve this design. But that’s well beyond my role as an inspector, and specifying such a solution would shift liability. I wish to describe the situation instead.

The post is three 2x4’s, flanked by two 2x6’s with nails and no lag bolts. The built up members were not painted or glued prior to assembly, and there’s no flashing on top. The deck has many other differences from a code compliant view.

Likely no action will ever be taken to “fix” this, so I need to write appropriately to educate all parties involved, and protect myself.

Additional photos at [https://photos.app.goo.gl/caP1U4Q7xMacd9M68](Photo Album)

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Looking at more of your images; I noticed the double ledger board against the house framing. I had one of those again. I don’t like it structurally, especially if the fasteners are defective in one way or another, or not visible. Even with no structural failure visible on that condition on my inspection last week, I did call it out as a condition to be aware of. It was working fine, but it’s not proper construction to have a double ledger located at an area where deck collapse often originates.

That is not a built up column in my opinion, at least not in a load bearing sense. The twisting of the inner 4x4 post independent of the sistered outer 2x4’s tells be they are not adequately bonded together. Those 2x4’s may prevent some moderate rotation of the beam… but not the post/column.

In other words, they are not doing squat. Beam to post connection is inadequate.

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FU (3)

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I would write it up so hard, my Inkpen would break - regardless of when it was constructed.
From only what I can see…
Post lumber dimension-to-length - wrong.
Post to beam attachment - wrong. (which usually means the stairway stringer support attachments are also wrong)
No diagonal support.
I can’t see the ledger hardware or the underside of the railing attachments… but if I was a guessing man… probably wrong.
And obviously - improper stairway handrails.
Call it out. Don’t take a chance with elevated decks.

Don’t even mention in your mind that “it feels sturdy” or “it’s been there a long time”. It’s wrong.
People use decks in different ways. Previous owner may have sat out there and read the paper, smoked a cigar, or used a bbq grill.
YOUR client may have 12 people and a keg out there. And they’ll all be leaning on the railing.

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Write hard!!

Call out the defects that you can see and state that it’s not built to current standards, poses a potential safety hazard, and that retrofits and upgrades should be considered.

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A home inspection is a snapshot in time. It is not a home inspector’s job to predict the future.

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I kinda feel like everything we do could be interpreted by someone as an attempt to predict the future. Lots of things work until they don’t. :man_shrugging:

I agree with Brian…

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Morning, Brian.
I concur. 4" x 4" inch post with dimensional lumber sistered to both sides. I enlarged a section. You can plainly see what appears to be a hexagonal lag-screw head every so many inches apart the length of the entire inner 4x4" post.
Likely the builder did not use washers and over torqued the lag-screws driving the heads of the lag-screws deep into the softwood pine lumber.

The notch created at the top, a critical axis intersection, by elongating the laminated lumber on the sides, created a cradle to retain the build-up beam in the build-up posts/columns. What the builder forgot, that critical intersection requires cross-bracing as well. Cross Bracing, between lines of columns, provides load path transfers. Horizontal forces to ground level, and much needed in this case but not there, lateral or side to side stability. Cross Bracing.
There is no cross bracing, no bridging/blocking/strapping between deck joists, and twisting, rotation and movement begins.

A deck is composed of many items; beam, columns, footings, joists, guardrails, decking and typically stairs, but connections holding it all together IMO is the most overlooked and misunderstood component. That photo you posted to me shows poor workmanship not only in the column, but in the beam it supports. My question, is poor workmanship/maintenance scattered throughout the deck? A deck is rarely in good condition by the time it’s 20 years old without exceptional maintenance.

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Randy, perfect wording. “Poor Workmanship.”
I cringe when I run into decks and balconies like this. I try to condense what I write up in that component. I feels like you can report framing defects and deficiencies forever. The more you look the more you see the more you report.
I would call deck this out. Suspect: Safety Hazard in various locations. Note: Do not use until further reviewed and made safe by a licensed carpentry contractor.
Just my 2 cents.