Thread: Never seen this before ?

Homeowner had built this deck about 10 yrs. ago. Deck had no band joist, self supporting anchored to 2x10 floor joist. Support posts didn't go to ground, as you can see in pictures the post were attached with bolts through to a double 2x10 that was cantilevered back 18". I usually see the deck support posts at the edge that go to the ground, not attached this way. I was concerned about weight distribution, but its been standing for 10 yrs. Any thoughts

By "band joist", do you mean the exterior board that wraps the outside of the joists? I've always called that the rim joist. In any event, the rim or band joist for this deck appears serviceable. It trims the end and helps prevent the joists from rolling.

I don't see any major crimes here. It's okay to have the joists on a short cantilever over the supporting beam. The joists are not properly strapped to that beam. You can't turn joist hangers on their side as depicted in the photo.

I don't follow what you mean about the posts not going to ground. One photo appears to show a post sitting on and secured to a concrete pier. If true, that's good. But there is soil over the pier and than is not good. The top of the concrete pier must be above the soil. The deck is heavily weathered and needs refinishing. It looks like a homeowner built deck which are rarely done correctly, but it doesn't look unsafe. Around here, by the time they look that weathered, I often see evidence of dry rot on the joists. The beam looks like pressure treated lumber, but I can't see enough of the joists to see if they are pressure treated.

Originally Posted by Lon Henderson

By "band joist", do you mean the exterior board that wraps the outside of the joists? I've always called that the rim joist. In any event, the rim or band joist for this deck appears serviceable. It trims the end and helps prevent the joists from rolling.

I don't see any major crimes here. It's okay to have the joists on a short cantilever over the supporting beam. The joists are not properly strapped to that beam. You can't turn joist hangers on their side as depicted in the photo.

I don't follow what you mean about the posts not going to ground. One photo appears to show a post sitting on and secured to a concrete pier. If true, that's good. But there is soil over the pier and than is not good. The top of the concrete pier must be above the soil. The deck is heavily weathered and needs refinishing. It looks like a homeowner built deck which are rarely done correctly, but it doesn't look unsafe. Around here, by the time they look that weathered, I often see evidence of dry rot on the joists. The beam looks like pressure treated lumber, but I can't see enough of the joists to see if they are pressure treated.

Yes band joist -rim joist , there's not a rim joist along the house wall, its a free standing deck. The posts from the roof going down along the railing don't go to the ground (that was main concern, I was concerned about teetering because the deck was free standing and not attached to house with lag bolts (no rim joist at house side) the weight from roof

Ahhhh, I see what you mean. The posts for the cover should either sit on the deck above the lower supporting posts or go directly to piers in the ground. I agree that they cannot be bolted into the rim joist.

This falls into that ever widening category of things not done to code or best practices, yet still functioning after years.

Yes the roof over the deck is not properly supported. I started to come up with sensible repairs but gave up.

If the deck is free-standing with posts at the house side, it needs lateral support, diagonal bracing, to keep the posts upright. I dig down around posts in the dirt to see if there is rot. In your area, termites will find those posts in dirt, especially if the ends are cut and not re-treated.

Originally Posted by John Kogel

Yes the roof over the deck is not properly supported. I started to come up with sensible repairs but gave up.

Originally Posted by John Kogel

If the deck is free-standing with posts at the house side, it needs lateral support, diagonal bracing, to keep the posts upright. I dig down around posts in the dirt to see if there is rot. In your area, termites will find those posts in dirt, especially if the ends are cut and not re-treated.

Found out today from the home owner that a permit was pulled and approved by the city inspector

Originally Posted by Sam Morris

[RIGHT]
Found out today from the home owner that a permit was pulled and approved by the city inspector

Sigh........

Originally Posted by Sam Morris

Homeowner had built this deck about 10 yrs. ago. Deck had no band joist, self supporting anchored to 2x10 floor joist. Support posts didn't go to ground, as you can see in pictures the post were attached with bolts through to a double 2x10 that was cantilevered back 18". I usually see the deck support posts at the edge that go to the ground, not attached this way. I was concerned about weight distribution, but its been standing for 10 yrs. Any thoughts

Hi Sam

Just a couple of thoughts here.
First off, there is a very strong possibility that the trusses have been designed to overhang the exterior without additional support. That would make the 4x4 supports merely cosmetic. I say that because from the pictures it does not appear to be any beam running the length of the roof line. Also, if the trusses were not designed to overhang, this would require the support posts to be supported directly on a beam or concrete posts in the ground. You would need to have more information on the truss design to make this call.

Second, the deck support posts need to be a minimum of 6" from the ground to prevent rot, pressure treated or not (at least here in NB). So as they are now, they may be prone to future damage.

Third, I believe what you are referring to as a band joist is a ledger board? The band/rim joist goes around the perimeter of the deck, excluding up against the structure. this is where the ledger board would be. And I apologize at this point if terminology varies from area to area and it is called a band joist where you are. Having said this, as long as the deck is resting on the proper supports, ie concrete footings, there should be no concern for attaching it to the home.

Cheers
Tom

It certainly is not a fine piece of engineering, but it may be ok. Considering the relatively small roof depth and the number of columns and bolts use, it may work. Without actually running the numbers I could not say.

IMO. almost no chance that the roof was designed to cantilever from the house.

Originally Posted by Mark Reinmiller

It certainly is not a fine piece of engineering, but it may be ok. Considering the relatively small roof depth and the number of columns and bolts use, it may work. Without actually running the numbers I could not say.

IMO. almost no chance that the roof was designed to cantilever from the house.

Proof trusses can be designed to cantilever,with many manufacturers saying as much as 1/4 the span is possible. I can't imagine any way to tack-on a 6-8' wide cantilever to an existing roof structure- you'd have to use doublers of some kind on the existing top cords - but I'm an architect, not an engineer. The deck structure does not look substantial enough to be carrying the roof load down to the rim/band joist, over to the beam, and onto the 4x4 post. In photo 1 it appears that there are anchor plates where the roof posts are bolted to the joist, making me wonder if some kind of problem-o occurred when the posts were lagged onto the joist.

Most AHJs require sealed engineering calcs for wood cantilevers great than 2', and most truss manufacturers provide sealed drawings/data as part of their service; either way those documents should be on-file with the building commissioner. I'd be raising the re-flag and recommending either additional research or an engineer's assessment.

Dave

Originally Posted by Sam Morris

Homeowner had built this deck about 10 yrs. ago. Deck had no band joist, self supporting anchored to 2x10 floor joist. Support posts didn't go to ground, as you can see in pictures the post were attached with bolts through to a double 2x10 that was cantilevered back 18". I usually see the deck support posts at the edge that go to the ground, not attached this way. I was concerned about weight distribution, but its been standing for 10 yrs. Any thoughts

Could you see the roof framing during attic inspection? Was the roof over the deck an add on or part of roof framing/truss.

In my opinion, that is not a cantilevered deck in the true sense of the word cantilever
Cantilever: A projecting structure, such as a beam, that is supported at one end and carries a load at the other end or along its length.
The beams that are perpendicular to the structure I highly suspect are not tied into the flooring joists and bear on the foundation.
But there is no anti sway.