WOW! The deck on a 3 year old house fell off?! Simply fell off? What if you had a party with a dozen guests on it?

First of all, you need to secure the doors so no one can accidentally walk out of one. It think the logical thing is to have another deck, but I'm very concerned as to why it failed. Was the house inspected as it was being built?

Hi, flgargoyle. Right, we've secured the doors. The deck had had temporary supports on it, placed by the builder, because we wanted to do some patio work and felt like the three 4x4's the builder had supporting the deck were insufficient, so were going to replace them. The temporary supports failed, but now that it's come off the house it's exposed the fact that although the builder says it was inspected and is to code, it most likely is not, there appear to be significant defects. We're in the process of finding that out from the Building Dept, etc.

We've thought of a two-story glass enclosed room in the back, which would probably be out of our league financially, but would like to come up with something different than the ordinary deck we had before. If you have any ideas we'd love to hear them. Thanks very much.

Looks like the deck was not properly attached to the home. Was it inspected by county? Most are attached to a strong thick wood beam like structure and then deck attached to it!
Good luck

Our builder said it was inspected, says it was all to code, which we are currently investigating. But I'd sure like some ideas from you guys about what interesting something we could put back here!

Our builder said it was inspected, says it was all to code

Free advice: Don't hire this "builder" to do anything more at your home. Decks built to the IRC Code just don't fall down unless there's been a natural catastrophe or they've been severely overloaded.

This was not an, "Oops, I dropped the hammer on my toe!" moment.

I'd stick with a deck. But this time attached to the house with more than a few nails. Or better yet, a free standing deck. But for better usability, I'd add stairs to grade.

Here is a link that might be useful: Building a Safe Deck

Thanks very much, worthy. I remember your good advice from when we were building this house. We left off the steps purposely so that bears and mountain lions won't come up there when we're sleeping out under the stars. We have both in the area. Thanks for the link, also.

Sorry I didn't offer anything in the way of a replacement- I just couldn't wrap my mind around the idea of the deck falling off!

I live in a warm climate, so my thought would be to have a screened porch on grade, and a walk-out deck over it. Basically, outdoor space for mosquito season, and non-mosquito season (if there is such a thing!) In a cooler climate, maybe a sun room downstairs and a deck above. There are very specific and effective ways to build an open deck above living space; make sure those techniques are adhered to!

"Looks like the deck was not properly attached to the home. Was it inspected by county? Most are attached to a strong thick wood beam like structure and then deck attached to it!"

Nothing is going to hold when the decks posts fails.

HOW it fell could indicate if it was fastened correctly.

If the entire deck tipped away from the house and fell that would tend to indicate it was not anchored correctly.

If it simply fell vertically as a piece when the posts failed it might have been attached correctly, the attachment is meant for vertical weight loading and pull away, not to hold the enotre weight of the deck when the posts fail.

I would be VERY reluctant to have this builder do anything.
Temporary posts should never have been left when the deck was completed.
The job was never finished correctly.

To the extent you had anything to do with allowing the shady work to remain (trying to save some $?) it may be your problem.

flgargoyle, I hadn't thought of a screened porch, and I was thinking a glassed-in room way to the top, which would be way too expensive. I'll suggest the screened room to DH, sounds like it might be a nice variant on what we had before.

brickeyee, it tipped forward, but the temporary posts, which were put there to substitute for the permanent posts which had been removed to be replaced, failed because the builder didn't do them strongly enough. The deck was finished three years ago; this was a new project to put larger support posts on because we thought the ones we have weren't enough (and now that I've read deck-building websites I see they absolutely were not sufficient) and because we were planning to have concrete work done below the deck. So we didn't allow any work we knew to be shady; the deck failed less than 24 hours after the temporary support posts were put on.

My first call tomorrow morning is to the Building Department.

Code in my part of NC doesn't allow for a deck ledger board to be attached through the siding, unless that siding is brick. Before you use anything from the original deck (like the footers), you might make sure they'll meet your needs (did they even pour footers?).

As for solutions, I'd make sure to get all the code information from your county on what types of posts and construction techniques, but I really like flgargoyles idea. We framed our deck, waterproofed it, and tiled the floor. That would make your screened porch nice and dry. If you go that route, make sure you use much larger joists and closer spacing. For our 16x16 slate tile, we had to use 2x10 joists 12" OC.

"Code in my part of NC doesn't allow for a deck ledger board to be attached through the siding, unless that siding is brick."

"Through the siding" or 'to the siding'?

Attaching to the siding has been restricted in many places for a long time unless the deck is engineered as a completely free standing structure that does not rely on the house for ANY support.

Simply going through the siding is not a big deal at all as long as the correct length fasteners are used and they end at suitable structural members.

The siding must be removed, the ledger board must be in contact with the house band.

One of the biggest causes of deck failure is due to the ledger rotting out. This is typically when installed directly over the cladding. By installing it directly to a band or to the framing, it gives an oppurtunity to flash out with a z-bar type flashing with the siding running down to that. The water runs down and over the ledger rather than behind it. You still get moisture behind so underlayment/self adhering flashings are important as well. When mounting a ledger over block, it's best to have mounting blocks and installing the ledger over those leaving a space between the ledger and the block.

To say why a structure failed if you would have to know a lot more about the structure.

At any rate, a deck ledger should be through-bolted to the house with horizontal flashing interrupting the exterior cladding. That doesn't seem to be the case here but there's no way to know if that caused the failure.

From the photo the posts seem OK except there doesn't appear to be any provision for lateral bracing and the posts look a little tall to be entirely unbraced.

I didn't understand any of the temporary vs permanent information. Why would the building department allow a house to be occupied with temporary structural supports?

I stopped using ledger boards a long time ago; there are simply too many ways to build the detail wrong and it is unlikely to be replaced when it inevitably needs to be. I use aluminum brackets through-bolted to the band joist and deck frame.

Here is a link that might be useful: deck brackets

Susanka's build isn't old enough for ledger rot,( I remember her posts a few years back concerning her build), and I wasn't commenting on what caused her's to fail, only commenting on running ledgers tight to the siding without it being properly flashed.

Whatever you decide, judging from the pics, the current ledger will need to be re-worked and properly flashed. From the top pic, It's assumed they ran the ledger over the lath before stucco which is fine when it is used in conjunction with a z-bar flashing and a perforated flashing above it so as not to interrupt any drainage plane for the stucco coats. Looking at the pics where you have stucco applied, the ledger doesn't appear to be flashed although it's hard to tell from pics. If it isn't flashed, now would be the time to get it done right depending on the project/application you decide on.

What I thought was a ledger in your pic now looks more like the scratch/brown coat where the ledger once was,( directly fastened over the scratch/brown coats), and the top coat stucco'd up to it. Definetely an improper install for the ledger not only for the lack of insufficient fastening, but again, no flashing.

Right, there was no flashing, but at the time it was built there was apparently no code requirement for flashing. The builder was here today, as was the inspector. Building inspector said there should have been a permit pulled for the temporary supports for the deck (which I didn't know, but of course the builder should have known), and now the deck will have to be built according to current code, which was just changed in April 2010. The old code didn't say anything about how closely lag bolts should be spaced. The bolts in the old deck range from 48 inches to 64 inches apart, which are only 4-inch screws. Nothing from the old deck can be used except the flooring and the railing, which is intact. There will be 6x6 posts, all new lumber around the rim, 6-inch lag bolts 16 inches on center, and I forget what else, but the build will be permitted, supervised, and inspected. It was all permitted when the house was originally built, of course, but the code requirements were much looser.

Sounds like you're back on track and despite the setback,( we have had a few), whatever you decide to replace back there, it will be worth it as I remember the million dollar view you folks have from the back! Best of luck!

Thanks, sierraeast, and everyone else. I think it's handled decently now.

The ledger (or a back board directly behind it) should be in direct contact with the house structure (not the cladding) so a 4" lag screw should be just as strong as a 6" lag screw (they both only penetrate a 1 1/2" thick lumber band joist or a 1 1/4" engineered rim joist). Flashing should be in contact with the sheathing, under the weather barrier, and over the rim board. If you want the drainage plane behind the cladding to be unbroken use the aluminum brackets I linked earlier. Flashing should never be uncoated aluminum since it will rapidly deteriorate due to galvanic action from continuous exposure to water.

The diameter and spacing of the lag screws should be determined by the actual sheer and pull-out forces of the deck (based on the regional snow, wind, and earthquake loading, as well as the effective joist span) rather than an arbitrary rule of thumb. I would place the screws in pre-drilled pairs one above the other and provide at least one through-bolt at each end. Two small ceiling patches is well worth it.

Provide adequate lateral bracing at the posts regardless of their size and anchorage; don't rely on the transfer of lateral loads to he house through the decking.

Don't use the building code as a structural design manual; it has already failed you once. The code is, at best, a minimum standard devised by people who don't agree on much and it cannot take into consideration individual conditions. Don't rely on internet deck design guides or chat room opinions (like mine). Don't rely the opinion of the local building official or your builder about structural matters. Find an engineer and get the design stamped.

I should mention that the 2003 IRC and most other building codes do establish standards for the design of outdoor decks but not in the same prescriptive manner as for interior floor systems.

The 2003 IRC requires that all floor systems be designed and constructed in accordance with the provisions of chapter 5 (FLOORS) ... OR in accordance with AF&PA/NDS (American Forest & Paper Association/National Design Specification). Since the design tables in the IRC do not include exterior decks it is necessary to use the standards published by the AF&PA for joist sizing as well as connector pull-out and shear resistance. Of course, the required snow load would be available from the local building department.

The '03 IRC also requires that "... decks shall be positively anchored to the primary structure and designed for both vertical and lateral loads..." and that "Such attachment shall not be accomplished by the use of toenails or nails subject to withdrawal. Where positive connection to the primary building structure cannot be verified during inspection, decks shall be self-supporting."

Thanks for taking the time to give us so many answers, macy. I've printed all of this out to show to DH. The previous builder, whom we met with yesterday after the building inspector came, when I asked him about flashing said he didn't put any flashing originally because he didn't want to break the seal of the paper,

The builder needs to learn how to properly deal with the structural design issues before making decisions about how to install flashing. For instance, he should have looked up the shear value of the lag screws he was using in the NDS.

By taking the easy way out regarding flashing and ignoring the structural requirements he created a dangerously weak ledger design. And adding more lag screws is not the appropriate solution at this point.

You should introduce him to the Maine Deck Bracket or a structural engineer before someone gets hurt.

The link below might be a good place for him to start his education. Keep in mind that the snow live load in your area might be greater than the 40 psf assumed in the article. In MA the snow live load is 60 psf and we're on the ocean.

I worked in Aspen in '66 &'67. It snowed so much a large old commercial building collapsed in the center of downtown. In the Rockies decks the size of yours should always be designed by an engineer, not builders or building inspectors. If an engineer is not available I recommend using posts on all sides in addition to through-bolting with spacers to the house.

Here is a link that might be useful: deck ledger options

We went freestanding for all our decks although they are small and not elevated as Susankas. I didn't want them attached to the house for many reasons. The drawback is that you have to have much more bracing, posts, header systems that dont always work with an elevated two story deck structure dependent on how openings in the lower and upper walls are layed out.

The structural principle that is overlooked by many contractors is that when two elements (a deck and a house frame) are connected by lag screws and the deck is loaded, the lag screw resists the load in shear (ie the screw would have to shear off for the support to fail). When the two elements are separated by a space that is filled with something that is not as structurally solid as the house frame, the screw becomes loaded in "bending" with the lever arm being the distance between the elements. Therefore failure of the connection would occur from bending before shear. This connection is much weaker than the first one and since the screw strength tables in the NDS do not account for the bending strength of screws there is no accurate way to design such a connection without further testing.

The Maine Deck Bracket avoids these issues by allowing the screws/bolts to act in shear (and pull-out) and allowing the tall web of the bracket to resist the bending force. Because of the greater pull-out force on the upper screws it is best to use through-bolts.

Susanka, it sounds like you have a great view up there, so I would go with a deck again. I do have a friend that has a two story glass enclosure like you are talking about. It is unique because part of it is floored in with deck type flooring and part of it is open to below. There are windows around the entire upper level and the view is beautiful.

A number of places no longer even allow the use of lag screws if there is ANY requirement for withdrawal loading.

The are demanding through bolts and nuts, along with enough bracing against racking in both direction.

Thank goodness no one was hurt!

If you are going to redo the deck area, why not make it wider? You could enclose part of it with windows that would take either glass or screens and leave part of it open.

I don't know the exact article link, but there was at least one article on Ask The Builder a few years ago about dangerous decks: www.askthebuilder.com/ Though one or more of the other numerous posts may have mentioned it, also check out general building sites like www.jlconline.com and www.buildingscience.com.

Also, there is no way a deck of this age should just fall off. Be sure to also check out www.hadd.com and www.hobb.org. Both are consumer orgs dealing with shoddy construction.

It is VERY fortunate that no one was hurt! This so easily could've become a tragedy, and IMO construction this unsafe should be criminal.

"In the Rockies decks the size of yours should always be designed by an engineer, not builders or building inspectors. If an engineer is not available I recommend using posts on all sides in addition to through-bolting with spacers to the house."

The picture above shows the classic pull away failure.
There is not a lot holding a band joist on except nails in end grain, and they are allocated ZERO strength in withdrawal for structural purposes.

Fairfax County, VA had a number of collapsed decks a few years back but has managed to reduce the number by careful attention to the code rules.
They cannot alter or change the statewide code, but they can make sure every requirement is met, and if the statewide code is silent they CAN promulgate rules.

Thank you so much, everyone. I can't tell you how much we appreciate your knowledge and suggestions. At the moment the patio is still being finished, so nothing on the deck will be done yet.

Happyladi, we have a 10-foot window just adjacent to the deck which we wouldn't want to put the deck under, and the land slants up to almost deck level at the corner of the house. We need to keep the deck away from any land where a bear could just saunter onto the deck because we like to sleep out there.

I'll post a couple of photos of our view, which indeed is just about the largest pleasure associated with living in this house.

Wow, what an amazing view. I'm glad you all are safe and that you have a plan for re-building a safe deck so you can enjoy that view!