I inspected a new home the other day that had a rear deck that was 9 ft above grade coming out of the second floor bedroom. The deck was approx 10ft X 10ft in size with 1 beam a 4X10 and 2 post holding up the beam about 8 ft tall. The post are 4X4 with 7 inch square footings. It reads in the deck guide here
on page 7 that all post are to be 6X6 nominal. Is this CODE?
Also the deck did not have any metal fasteners besides nails connecting the joist to the deck. The joist canterleavered the deck by a foot and a half and the rim was screwed to the joist only thru the ends(with angle connectors). Also there was no sway bracing and when I was on the deck I could make it rock back and forth with my feet alone.
Well I called this out and a engineer came back with a letter stating it was fine and within code.
The main point is, is it a code requirement to have sway bracing and 6X6 post?
The 2009 guide you posted is based on the IRC. As for back to at least 2006 6"x6" post have been require by IRC.
2006- POST REQUIREMENTS [R407]
All deck post sizes shall be 6x6 (nominal) or larger, and
the maximum height shall be 14’-0" measured to the
underside of the beam. Posts shall be centered on
footings. Cut ends of posts shall be field treated with an
approved preservative (such as copper naphthenate)
[R402.1.2]. The beam shall be attached to the post by
notching the 6x6 as shown in Figure 8 or by providing
an approved post cap to connect the beam and post as
shown in Figure 10. All 3-ply beams shall be connected
to the post by a post cap. All thru-bolts shall have
washers at the bolt head and nut. Attachment of the
beam to the side of the post without notching is
Common sense tells you if the deck sways back and forth it needs bracing.
Your photo also looks like the guardrails are missing 4x4 post, which are required every 6 feet.
The State adopted the 2009 IRC and I didn’t find an exception listed in the WAC. Those requirements were also in the 2006 guide. I stick with the 6x6 and notched for the beam.
I just did a year old home on a warranty inspection. 16 feet in the air on 4x4 with no diagonal bracing, no flashing and just a few too small lag bolts on the exterior of LP siding. This is a death trap waiting to happen. I could get the deck moving very easily by just shifting from leg to leg.
I would love to see the “code” the engineer quoted. Probably an aircraft engineer…
Ditto, and there are more defects that I would report, and prolly even more if he provided close up pics. My comment above was in regard to the actual questions as posted by the OP. I was focusing more on the structure than the guardrail etc…
Good info. It’s not the connections that are the problems. The AHJ in my area requires 4’ deep (18" min. footing) with 10" concrete piers. (6" above grade) Deck height 60" above grade requires a 6x6 post.
In the deck photo of the OP, it looks like the pier close to the house is already leaning outward. Probably not even 3 ft deep.
He has performed calculations which address whether the actual construction can handle his assumed loads, but his statement regarding it being up to code can only be confirmed by which local standards are being used. He signed off on it so it’s on his head now; Breathe easy, stand by your report and have a drink.
This is a balcony, not a deck, since there was no stairway to the ground. 4x4 is fine, many, many decks and balconies have been built with 4x4 with no problems.
The nails will eventually back out due to thermal cycling, but it’s not a defect, it’s just fastening with nails, which are not as desirable as screws, which won’t back out. It’s a quality issue.
Screws through the rim into each joist are better than most of those connections that are typically just nailed, since those fasteners are exposed mostly to withdrawal forces, rather than shear. Actual metal connectors other than fasteners for that connection would be unusual unless the deck were high-end.
The cantilever is fine.
The diameter of the footings beneath posts is not as important as their depth, although this can vary with soil type. requirements vary with local frostline depths. Did you see signs of failure?
The fact that it’s tied to the offset wall means that it’s supported laterally and will reduce the need for diagonal bracing. Lateral failure is usually due to things like people dancing and moving in unison to a beat. Whether or not it’s potentially dangerous is a matter of degree and judgement on your part. Diagonal braces are inexpensive to install.
In general, this looks fine to me. The lack of 4x4 posts to help support the handrail is something I’d check out. I’d expect some lateral movement in the handrail due to their lack which would grow worse with time as expansion and contraction of the fasteners enlarge the holes fastening balusters.
All the code stuff and Simpson Strongtie stuff are not your concern, since you are not performing a code inspection and this was not built using engineered lumber. Your concern is safety and system failure. This deck is built using very common methods.
You go ahead and say this is fine! But I would not even think about going on that decking or balcony. As for the cantilever it would be my concern for sure as you now have extra force upward on the ledger board which is transferred to the joist hangers.
One thing to think about…When they take a family photo where is everyone going to stand?
BTW it really is not considered a balcony.
Ditto. This deck is NOT fine! The cantilever is too great and the 4x4’s are inadequate. I have been building decks professionally for 25 years part time, and on average build 5 decks per summer. The AHJ in my area would laugh if plans were submitted to build that deck in the photo. Obvious to me that it was build without a permit, or never had the required inspections during construction. Every deck I’ve built, the AHJ comes out 3 times. First to inspect the footings (depth/pier dia.) before any concrete is poured. Second to inspect the structure. Third (Final) to check the railing and stairs.