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It's Almost Deck Collapse Season!!

Brace Yourselves, Deck Collapse Season is Coming

Ah, spring is in the air! The birds are chirping, flowers are blooming, and decks across the neighborhood are being hosed down in preparation for backyard barbecues and beer-fueled hang-outs.

But let's be real here, folks. With the onset of warm weather comes an annual rite of passage that strikes fear into the hearts of homeowners, safety inspectors, and personal injury lawyers alike - deck collapse season.

Yes, you heard that right. Soon, unsuspecting groups will be gathered on rickety residential decks, obliviously sipping their spiked lemonades while the ticking time bomb of shoddy construction and poor maintenance lurks beneath their feet. Inevitably, the laws of physics will activate with cries of "Timber!" reverberating through the air as people come crashing down in an ungraceful pirouette of splintered wood and twisted limbs.

It's a comic scene straight out of a sitcom until you realize people can get seriously hurt or worse when a deck gives way. Flying shards of decaying wood are not friends to skulls or torsos. Not to mention the mental anguish of having your cornhole championship cut short so abruptly.

So, what's behind this annual menace? Sadly, a combination of factors enables deck disasters year after year:

Contractors cutting corners on deck construction, perhaps hoping the shoddy work holds up just long enough to cash that final payment check. Unscrupulous builders purposely ignoring code to save a quick buck are essentially selling ticking time bombs to unsuspecting homeowners.

Local building authorities failing to enforce codes and ensure decks are built to withstand the loads they'll encounter, especially when Joe Sixpack and his buddies congregate for a round of Vitamin R. If towns rubber-stamp deck permits without inspections, they're putting lives at risk.

Good property maintenance practices are being neglected by homeowners who ignore deteriorating deck boards, wobbly guardrails, and rusting structural components. That bowl of melted cheese isn't the only danger lurking at your upcoming Cinco de Mayo bash.

The unfortunate reality is that preventing deck collapses requires vigilance from builders, code enforcers, and homeowners alike. Shoddy deck construction is no laughing matter when it can leave people with broken bones, spinal injuries, or worse, from a dangerous plummet to the ground below.

So, this season, look like a gift horse in the mouth when it comes to decks. Get those neglected spaces inspected and repaired before stocking up on Pabst Blue Ribbon for your rager. An ounce of prevention is worth avoiding the prospect of going viral in a deck collapse fail video that will make you cringe for eternity. After all, no one wants to be a literal social media sensation.

Stay safe out there, dear readers! Keeping decks up to code could be a matter of life, laughter, or spinal cord injury. You've been warned – deck collapse season is near.
 
Our biggest problem is the homeowners and fly-by-night "contractors" who persists in building decks without benefit of permit -- or inspections.
 
Aging decks, built when there were not sufficiant provisions in the code, largely ignored altogether. Ledgers nailed to who knows what, etc.
 
I have to add, the pervasive attitude of many building departments to treat decks as afterthoughts.....and that usually comes from the top down. After all, it's just a deck.
 
One of the worst things I need to do is to require a engineer when they are building a roof over a deck because the IRC does not have anything on piers supporting both a deck and a roof.
Today I will be inspecting a few decks that were already built without a permit, some may have a roof.
 
One of the worst things I need to do is to require a engineer when they are building a roof over a deck because the IRC does not have anything on piers supporting both a deck and a roof.
Today I will be inspecting a few decks that were already built without a permit, some may have a roof.
About a month ago we did a stop work for a person who built a roofed over structure over his existing 10 foot tall deck (balcony - with permit 7 years ago) We required him to take it down and get an architect to design it. And he has so far has complied. Unfortunately, the new architect plans cannot be approved since they lack too much information. Maybe they can get this done but it will be a bit of back and forth with this particular architect.
 
One of the worst things I need to do is to require a engineer when they are building a roof over a deck because the IRC does not have anything on piers supporting both a deck and a roof.
Today I will be inspecting a few decks that were already built without a permit, some may have a roof.
So can't build a porch prescriptively by IRC?
 
18 years ago this was the only code sections referencing "decks". 2018 we finally had a prescriptive section to follow.
BTW a big thanks to Glenn for his time, energy and expertise in getting R507 into the 2018 IRC.

2006 IRC
DECK. An exterior floor system supported on at least two opposing sides by an adjoining structure and/or posts, piers, or other independent supports.
R502.2.2 Decks.
Where supported by attachment to an exterior wall, decks shall be positively anchored to the primary structure and designed for both vertical and lateral loads as applicable. 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. For decks with cantilevered framing members, connections to exterior walls or other framing members, shall be designed and constructed to resist uplift resulting from the full live load specified in Table R301.5 acting on the cantilevered portion of the deck.

2018 IRC
SECTION R507
EXTERIOR DECKS

R507.1 Decks.
Wood-framed decks shall be in accordance with this section. For decks using materials and conditions not prescribed in this section, refer to Section R301.
 
So can't build a porch prescriptively by IRC?
A porch and a deck are not the same thing. You would not use section R507 when constructing a porch.

Porch vs deck​

A Porch is a covered structure that is attached to a house, usually through the front or back door. It can be open-air or enclosed, usually with screens or glass. Porches are often used for welcoming guests, relaxing, and enjoying the outdoors. They are typically part of a house’s architecture and share a roof with the rest of the house.
On the other hand, a Deck is an open outdoor structure that is attached to a house, usually in the backyard. It is often elevated on stilts or pillars and can be made of various materials such as wood, composite, or metal. Decks are designed for outdoor living, entertainment, and recreation, and are often used for activities like grilling, sunbathing, and socializing.
Some key differences between porches and decks include:
  • Coverage: Porches are covered, while decks are typically open to the elements.
  • Location: Porches are often located near the front or back door of a house, while decks are usually in the backyard.
  • Purpose: Porches are designed for welcoming guests, relaxing, and enjoying the outdoors, while decks are designed for outdoor living, entertainment, and recreation.
  • Design: Porches are often part of a house’s architecture and share a roof with the rest of the house, while decks are a separate structure that can be designed to match the style of the house.
In summary, while both porches and decks are outdoor structures, they serve different purposes and have distinct characteristics.
 
So can't build a porch prescriptively by IRC?
For me it gets iffy. I stretch out the codes a little for small porch roofs, but it can get pricier than using an engineer, and I can only stretch so far. I use the tributary loads for the deck, then add the tributary load for the roof as if it were a deck. SUPER conservative, as when snow load is present, people usually aren't, but that's not guaranteed. That gets me the footings. The IRC does offer prescriptive beam sizing for smaller porch roofs, so I can use that. Columns.....well a 6x6 can handle just about anything. Uplift, that gets dicier IMO, but I can use the IRC for rafters, and beam to column, and column to footings to get a load path. By this time, most people find an engineer, or they spend more on overkill than they would have on an engineer. Then it comes down to judgement, some people say I use it well, others don't. Proactive AHJ's have well thought out publications (I poach them when I find them). Some guides I have seen do more harm than good. Fortunately, I see residential projects very rarely now because these were always a PITA.
 
Thank you sifu. My post was based on:
One of the worst things I need to do is to require a engineer when they are building a roof over a deck because the IRC does not have anything on piers supporting both a deck and a roof.
I otherwise would have agreed with you.

My porch from below looks like a deck - ledger, embedded 6x6s, p.t. 2x6s (ok for spans with some doubled), 5/4 x 6 p.t. decking. Roof is on turned wood p.t. posts. I assume roof is framed like any roof but will investigate.

I just want to build a small addition (code should prohibit porches less than 6' deep - useless i.m.h.o.) and was assuming deck of codes for framing to floor, 6x6 posts ("can handle just about anything"), and IRC wood roof. I'll do a footing at frost depth, size based on soil, formed concrete pier, and a 6x6 bracketed on it. Still wondering are live loads just snow on roof (60 psf here) and just people (40 psf) on floor?
 
Most of the time the owner wants to build a roof on an existing deck that never had a permit. I do allow a roof to be built over a deck when the roof does not use any part of the deck piers for support using the deck pier table because our snow load 40 psf is the same of the live loads on the table for decks.

What do you do with the piers when they want to enclose an existing roofed deck using walls and windows, which would make it an addition, using the existing piers?

We see a lot of things built on piers here besides decks. I always though it odd that the IRC did not have tables for piers for other things besides decks.
 
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Most of the time the owner wants to build a roof on an existing deck that never had a permit. I do allow a roof to be built over a deck when the roof does not use any part of the deck piers for support using the deck pier table because our snow load 40 psf is the same of the live loads on the table for decks.

What do you do with the piers when they want to enclose an existing roofed deck using walls and windows, which would make it an addition, using the existing piers?
The existing piers would have to be dug up to verify that they are big enough and deep enough. We would let you keep existing piers if no extra load is added, but if you add anything we gotta see them.
 
A porch and a deck are not the same thing. You would not use section R507 when constructing a porch.

Porch vs deck​

A Porch is a covered structure that is attached to a house, usually through the front or back door. It can be open-air or enclosed, usually with screens or glass. Porches are often used for welcoming guests, relaxing, and enjoying the outdoors. They are typically part of a house’s architecture and share a roof with the rest of the house.
On the other hand, a Deck is an open outdoor structure that is attached to a house, usually in the backyard. It is often elevated on stilts or pillars and can be made of various materials such as wood, composite, or metal. Decks are designed for outdoor living, entertainment, and recreation, and are often used for activities like grilling, sunbathing, and socializing.
Some key differences between porches and decks include:
  • Coverage: Porches are covered, while decks are typically open to the elements.
  • Location: Porches are often located near the front or back door of a house, while decks are usually in the backyard.
  • Purpose: Porches are designed for welcoming guests, relaxing, and enjoying the outdoors, while decks are designed for outdoor living, entertainment, and recreation.
  • Design: Porches are often part of a house’s architecture and share a roof with the rest of the house, while decks are a separate structure that can be designed to match the style of the house.
In summary, while both porches and decks are outdoor structures, they serve different purposes and have distinct characteristics.
So is just an outside landing a deck?
 
I always though it odd that the IRC did not have tables for piers for other things besides decks.
Amen to that. Not too hard to figure tributary areas with LLs and DLs.

I agree a pier supporting both deck/porch and roof needs to be designed for the aggregate loads. Didn't understand someone was adding a roof over existing deck. (Does it become a porch or only if attached to a house and accessed with a door from the house?) I struggle with a deck only being designed for either the live load of people or snow, whichever is greater, but maybe justified.
 
One of the problems with an "addition" with walls and roof enclosing a space is the lateral load. As far as I know there is no prescription for a braced wall on an isolated pier. But I agree, especially in a former state, lots of things were done on piers, but usually ended up with an engineered design.

Where I am now, they use deep caissons for decks and porches, which have zero prescription, but are arguably better than a deep footing with an embedded post or CMU pier. Prescriptively we have no choice but to use the footing table for the caissons, but I am a little more forgiving on that and use a calculator for that when I can. Prescriptive code can't possibly cover everything, but everything not covered wouldn't necessarily require an engineer IMHO.
 
One of the problems with an "addition" with walls and roof enclosing a space is the lateral load. As far as I know there is no prescription for a braced wall on an isolated pier. But I agree, especially in a former state, lots of things were done on piers, but usually ended up with an engineered design.

Where I am now, they use deep caissons for decks and porches, which have zero prescription, but are arguably better than a deep footing with an embedded post or CMU pier. Prescriptively we have no choice but to use the footing table for the caissons, but I am a little more forgiving on that and use a calculator for that when I can. Prescriptive code can't possibly cover everything, but everything not covered wouldn't necessarily require an engineer IMHO.
Well, you usually show reason.
 
So is just an outside landing a deck?
The term landing when used in the means of egress portion is usually defined with the minimum dimensions required within the code. Exceeding the area/dimensions used to define a landing, the code will use a couple of descriptions such as floor, porch, balcony or deck.
Every door, stair, ramp or elevation change has a required landing area.

The answer to your question IMHO is the AHJ will determine if what is being constructed is a landing or is the landing area just a portion of the deck being constructed.
It is one of those words in the code that is used in a number of code sections with different requirements.
doors, stairs, helicopter landing, area of rescue assistance, and elevators to name a few.
 
I was just nosing around and found this submittal for a patio cover for one of the AHJ's I do not normally work with. Based on the elevations the trusses are scissor trusses, otherwise this is the extent of the structural plans. How many think this could be approved without an engineered design, albeit with a little help?

This is only a thought exercise for those with a minute to burn.

1715354508341.png
 
I would approve these plans all day long. Sized the beams with BeamChek and they work, footings are plenty big enough assuming the roof is a 30lb live load and a 10lb dead load. I would spend more time trying to figure out the zoning for the lot than reviewing it for code.
 
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