NOTHING you put out is boring! That is why we follow you for greater understanding that we are riveted to learning. (laypersons) Thank you sooo very much for all that you do to use this to educate folks who then may champion in their districts and communities. What a service you have done, thank you so much for CONTINUING and not giving up on educating through us lay folks to an end which may affect others.

Another fascinating video, this is the sort of involved detail that the average layperson would probably never even stop to think about when looking at a building. I've honestly learned so much since I started watching this channel.

A hole story... In our building we have four floors: B, 1, 2, 3. But do we? Below the basement level is the dungeon: [and this being a monastery you can imagine what medieval appliances might be in there] It is a set of tunnels for water and steam return pipes to live in. Off of this there are some chambers that once upon a time gave access to pipe chases leading to other buildings. Here there be sump pumps. This dungeon level then turns left, that is to say west and continues for another 50 feet or so, but the floor rises up so much that only a cat could pass through it. And the last time I checked the cats are not licensed plumbers, welders or electricians. But the utilities are in there none the less. At the distal end of this tunnel there is a right hand turn and it opens up into a basement level tunnel. A brick lined tunnel that goes under the parking lot to the power house building. Off of this tunnel there are chambers that housed condensate return equipment (now disused--but with an access to the sidewalk above), and another tunnel with a sandy floor that takes pipes to yet another building. But to continue with our first (or was it the second tunnel?) we enter the basement of the power house where it circles around the platform that supports our boilers. I have gone through these tunnels to install CAT-5 cables for our computer system. Perhaps I should have had the spiders to the work, there sure were enough of them. And so once I got to the power house I found a conduit through which I could introduce my cable, and there install a network switch, for I still had to go back down into the tunnel to bring the cable to the next building in our complex. But wait, this is not all! For above the third floor there is the attic, and this too had to be fitted with fire sprinklers, but this had to be a dry-pipe system, since here in North Dakota we would not want pipes the the attic, or even on the un-heated floors to freeze. Then above the attic is the roof. The south and east wings are peaked, but while the north wing pretends to be peaked it really has a flat roof, and has ventilation machinery located there on. Dungeon, Basement, First, Second, Third, Attic, and Roof, that is a lot of building any way you count it. But now, I am 74 years old, and so someone else will have to maintain this stuff.

Most of us found you and your channel because of your explanation of the Champlain Towers collapse, but it's become so much more than that now. You're a great resource for helping people understand how buildings are built and maintained. The way you explain blueprints makes it easy to comprehend. You've also taught us about the "politics" of a project. I enjoy knowing that you and your channel are making me smarter every time I watch a new video. Josh, thanks.

In Surfside a story is whatever your lawyers say apparently.

Excellent video! You should do an analysis on the old Glass Bank building that used to stand in Cocoa Beach. That building was an engineering marvel at the time it was built in the 1960s during the space race, but turned out to be ripe with engineering failures, a co-owner who added two windowless stories to the roof some 15-20 years after it was built (lots of corruption and scandal), and who lived in that penthouse almost a decade after the rest of the building below was effectively condemned from hurricane damage and the need and expense that the other co-owner didn’t want to spend to bring back up to modern fire code in order to make functional and habitable again. I’ve always been interested in the structure and history of this building. Thanks again Josh!

Fun fact: What you call the first floor here would be called Erdgeschoss (ground story) in Germany. And the second story would be called the first story.

This may sound naive, but shouldn’t commercial buildings or multi-family buildings always be held to the higher standard because of the potential for harm to a large number of people?

You learn something new every day... I had no clue the American spelling of "storey" is without the "e". ( not being sarcastic) . Great video as always!! I've been watching all your Surfside collapse videos. Extremely informative!!

This was a very interesting lesson about differences and definitions of building codes etc. I was immediately reminded of a Coen Brothers film from the early 90's called the Hudsucker Proxy. The movie started out with the sole proprietor of the company jumping out the 44th floor of the Hudsucker Building, to his demise. As the board of directors convened afterwards, the company president, played by Paul Newman, speculated as to why the man jumped 44 floors to his death but one of the directors interjected that there was also a mezzanine at the ground floor. That caught my attention and for the past 30 years or so, I thought the character may have fallen 45 stories, "including the mezzanine," and not 44. Now I know correctly it was 44 stories.

I think it would have been good to go at least a little bit into what Section 505 says about mezzanine floors in the video - at least mention the fact that if the floor area is too large relative to the floor underneath, you can't call it a mezzanine any more and have to call it a separate story (with an atrium connecting the two stories).

I could listen to you for hours, makes me wonder if I missed my calling in life. Love to hear you break down the new laws and if they help more than hurt. Thanks Josh.

OK I get your example. I worked for 34 years in a hospital which was on a hilltop site. On one face the grade level entrance was at the Basement level. On an adjacent face was a grade level entrance on the Ground floor (one level above the Basement), and on an opposite face there was a grade level entrance on the First floor, (two levels above the Basement.) There were the following occupied levels: B, G, 1 thru 9, plus a 10th floor restricted access mechanical floor, and a restricted 11th floor elevator machinery level. So it can get pretty technical on how many stories a building has.

Very good presentation of a moderately complex topic to those of us with little understanding of engineering. Thanks!

I would be curious if the engineer didn't have to change anything in Surfside because the penthouse was ALWAYS there in the design but the Arch/Owner knew they had to play games with the drawings and submissions to get it "legally" built?

As a Florida resident, I believe that zoning restrictions mean nothing. It only takes minimal political influence to obtain a waiver. Additionally, the building inspectors do nothing regarding flagrant longterm violation of zoning restrictions. Pitiful.

After watching your videos I always feel like I learned more than in most of my college classes.

This entire issue, grade level, story count on stump(stilt) construction etc has plagued the local city council here in Brisbane, Queensland, Australia, to the point where the council recently just gave up trying to enforce code, just allowing owners to modify to whatever standard. Brisbane is a hilly River city, and until the 1970s, most residential buildings were entirely timber construction, mounted on stumps…stilts..to deal with whatever undulating contour issues the plot had. Constantly flooding areas were originally allowed to raise underfloor ‘head heights’ to exactly nine foot, however, in many areas this provision failed to protect the dwelling from flood. Legal process from litigation, insurance, stubborn owners etc. continued to create such a Grey zone of non compliance where the Council simply decided to allow a free for all. This provision only applies to existing buildings, the locally known as “Queenslander “ houses, timber buildings surrounded by a wide veranda, rooms within having french doors access to the veranda to allow cooling breeze in Humid Summers. This type of building are impossible to complete to modern code standards, so are no longer built here. Most carry a heritage listing, further complicating any modification work.

You are so right -every word in the law is important. I almost missed my dream because I took the common meaning of the law to mean all of a class, when it did have an exception. That one word made all the difference.

OMG!!!!!!! I have just heard after listening to you since Surfside something that affects me personally in another state. You stated that insurance has to cover new laws and ordinances on top of their coverage. Just happening RIGHT NOW to me with a new roof as the codes have changed, and they now must do by codes a freeze thingy (lol whatever is called) and they MUST do a metal thingy from the boards of the roof to the front of the such/behind the gutter. Wow! The thing that the insurance company said is the roofer must prove! Wow! Thanks and I couldn't figure out what they were talking about as to such until your video!

It would be nice to see a video explaining how the International Building Code defines a penthouse as a storey. Canadian building codes clearly define a penthouse as a roof top space used only for service equipment.

Shady as it might have been, I dont believe it was a major factor in the collapse. I think the main issue was the water intrusion on the pool deck weakening the steel reinforced concrete of the parking garage for decades. Other than targeted draining and proper waterproofing, I think maybe engineering steps to avoid domino effects as much as possible should be emphasized on. I think the spalling was from the water and not from being overloaded? If the penthouse would cause an overload I think the damages would have looked diferent? Would be interesting to see typical overload characteristic damages as an example in a video, I think it could help HOA's be more aware of upcoming problems.

I used to work for the John D and Catherine T MacArthur foundation and back in the day John MacArthur wanted to put a 13th story on the building. But as he had the tallest building at the time the town had set the height limit to be that particular building’s 12th floor ceiling. As MacArther was a rich stingy lawyer, he lifted the 12th floor and inserted an 11 B underneath.

Love your videos Josh. You always enlighten us on the building codes that we would other wise be clue less about. Thank you...!!!!

When I was a county inspector I faced this problem. A new high rise jail needed a rooftop equipment room larger than code allowed without calling it a story. The need was driven by redundant equipment to keep the jail operating during equipment outages. We ultimately went to the state board and we’re granted a variance. Thank you for the video.

Another great video, Josh! You chose a really good example to illustrate things. Thank you!!

You are SO good at explaining all the technical details so laymen can completely understand. Thank you! ❤

@Josh: Could a builder/architect game the 'mezzanine' rule by simply having an atrium with a curtain wall going straight up to the ceiling while having multiple mezzanines, or even having an open space through the middle of multiple floors as we see in many open office buildings? Some examples would be the Luxor Hotel Las Vegas and the NY Marriott Marquis

I find this really odd as a conclusion. Does this mean that I could have a skyscraper count as a single story building if I don’t have complete floors inside, but just a lot of mezzanines? When does a mezzanine become a floor? Is it good enough if I have an attium where I can see the ceiling 500m above me?

Your videos are quality for both professional engineers and average citizens to learn from

Appreciate all your efforts with these breakdowns and that's all the way down here in New Zealand.

Great video, as always! I've learned more about reinforced concrete buildings in the last year just watching your videos than I have during 5 years in university. Which isn't that surprising given what my chosen specialty was...

Hi Josh, I am not sure if you can access it form the US, but the BBC has released a 1hr documentary on the collapse - Why Buildings Collapse. Some interesting survivor interviews and additional footage. Thank you for the fascinating content, I have learnt a huge amount from watching your videos.

I watch everything you create! Keep it up!

Great job with your video and the explanation!

Your video refreshes the thoughts of some of us even because we may build a home that is three story and includes two mezzanines. To top that off there is also a dome. Issues came up early, in the design process, most particularly in how high the county would allow the dome to rise. That latter point can guide where you build in Florida.

Thank you Josh, this is actually a question I had from the start. It struck me at the start when I counted the floors but there was never mention of a 13th story after the collapse. That led me to the council, the money, why was it considered 12 stories etc. 🤷🏻‍♀️

Thank you! I have wondered about that since it was disclosed early after the fail.

Hi Josh, thanks for sharing. I leave comments to those that have already given great insight's to this subject. Personally after watching this video, your clients building is a 2 (two) story building. I go through them and click on the thumb's-up.

One tiny fact would have made this a lot clearer. Mezzanines can only be so large as compared to the story they are on before they are no longer a mezzanine. I was confused until I read the comments. Otherwise, quite a good video. I now know a little bit more of how much I don't know.

Thank you for sharing your knowledge and experience

Great Video Josh!

I eagerly look for new videos when you post them. While I first found your videos of CTS, everything I have watched is just top notch. We’re I in need of structural engineering services, I would look no further than your firm. Just excellent content!

Very interesting and well explained, as always Josh. Thank you! (I incorrectly guessed three stories, now I know!)

Josh, you are very good at what you do!!

Another great video from Josh.

Great video, thanks for the education!

Thanks for another great video!

Thanks Josh! Love your stuff, keep it up! How's Millennium Tower looking these days?

Thank you, Josh. Really interesting.

Josh, Great video! Thank you for explaining these complex issues. Paul (in MA)

Another amazing video!

Good video of commonly used names for various levels in a building. One level that was left out is an interstitial space. Common in hospitals and jails. This level is very similar to a mezzanine, in that it is an intermediate level in tall stories. But where a mezzanine is occupied or used for storage. An interstitial space is used exclusively for HVAC equipment or other building systems. Access is by maintenance type persons.

Wow, so much of this seems so nit-picky, but, of course, that is what supports the whole legal (lawyers)profession! Thank you for all your effort and research to explain the minutia of building code definitions, and where problems in definition of spaces could arise. Gives me a headache just thinking about it!

Fun fact: In Denmark & Sweden the 2nd story is called the 1st floor.

Just what i expected! This is indeed tricky to determine. More so when English is not your first language and some words being not that clear to what it means. lol Thank you for always come with a clear explanation on these topics, makes it really easy to follw and understand. Have a nice day...

Incidentally, I recently worked on a mass transit system. In the case of a metro station, the mezzanine level is a floor located between the platform level and the ground level that allows you to go from one platform to the other (in the case where there are two platforms, one on either side of the track) and to the stairs or elevators that lead to the ground level. It's essentially the level that connects the various parts of the metro station. When you have a cavernous station, it often takes the form of a bridge crossing over the tracks. If you have elevated tracks in the middle of a boulevard and the access to the station is a building on the side of the boulevard, then the mezzanine will appear to be a pedestrian crossing over the traffic lanes of the boulevard, between the aerial part and the ground level part of the station.

Always interesting watching your videos

🤯 Thanks for these videos!

Back in the 1990s, while working with Cave Research Foundation, we discovered a place inside a cave in Arkansas where there was an intermediate area, higher than the bigger room to which it was an extension, but lower than the "upper level" passages that fed into it. I scoured through dictionaries and thesauruses and probably some architecture books to find out what this "intermediate elevated" spot would be called in a building and discovered the term Mezzanine! Had not heard that word for decades!

Remember in the 70’s when split level homes were all the rage? Lol

Excellent analysis.

4 stories. Love your videos!

NYC has a local law #11 governing facade repair that applies to buildings taller than 6 stories. NYC has a local law #97 governing energy usage and efficiency that applies to buildings larger than 25 square feet. NYC has a site safety regulation that applies to buildings 15 stories and taller. All of these laws are very expensive to comply with and make repair and construction work much more expensive.

This was really interesting since I currently live in a building that has a similar design as your example building. We have the split level part in the lowest part though. I think it's a little more clear-cut in our case because the part that is a little bit higher only has a crawl space below it. I can see why it is and ought to be considered a two story building. As a former firefighter, I don't want to arrive on scene at a building collapse and have people tell me the number of stories based on how many stairs there were. At the point of split levels and lofts, it is more useful for people to tell me how many main stories there were. Of course, in the case of our local areas, it was part of our training to know what they were like under normal conditions but, in the case where we are called out to other areas, it's better to keep it simple. I don't know what our codes for actually building are here, but I do know that we had to build a damn 6 foot block wall up to a code that was supposed to withstand a 9.0 earthquake and 90 mph winds simultaneously (neither of which have ever occurred here to our best knowledge) so I'm sure the actually buildings are pretty damn good around here.

Excellent as per usual Josh, I guessed two stories. Thanks for sharing.

As a Realtor, I would list it as a 2 story with a loft.... but really it's a 3 story

Thanks’ for teaching me something new! I didn’t know a Mezzanine and a Loft was the same thing. Now getting back to the Video to me it’s a 2 Story Building. Mainly because Mezzanine/Loft is not a complete floor.

Great Video!

another great video under the rules the first 1 is main floor as long as it docent exceed 12ft to grade The mezzanine can be considered a grey area that could depend on its usage and if its used as a liveable story or just a storage but even that has interpretations and i can already see methods to abuse a mezzanine to hide a floor I would say technically its 2 story but may be viewed as 3 in the future as loop holes are removed

Without the benefit of the cross-section, if I were simply driving by that house, it would appear to me as a 2 story with possibly a cathedral ceiling upstairs. and so this is why the technicality is so important. very good. I wonder if they could have fooled an inspector driving by.

"Falls in this gray area". Very true, it fell into a big gray pile, last summer.

I work for an insurance company. Since square footage is one of the many criteria we look at, we would calculate this as a two-and-a-half storey home.

I love this! I’m guessing that, unless the parking garage under the building or down to finished surface or grade level is over 12 ft, it would be a two story since the mezzanine wouldn’t be a full story on its own. I may be wrong though!

Another excellent video. I do wish you had circled back to the Champlain Towers South case. I know this wasn't primarily about that. But the intro does mention it. It would have been nice to see the principles applied to that example. I'm suddenly wondering if the builders argued that the penthouse was a mezzanine and on what basis.

What a lovely story on a Saturday morning!

Props to your client for even caring

I'm not a professionally trained blueprint reader, but it looks like the house in your example has a symbol indicating "orient your self from here" and it says "ELEV + 13'. 0" TOP OF FIN FLR". Now I take that to translate to "from this point, which is the top of the finished floor, the elevation is 13 feet and 0 inches". This makes sense to do if the blueprint maker doesn't want to show 13' of stilts to scale, but at the same time, it would be bold of you to intentionally say 3' for the stilt size when the actual size is 13' because it would actually change the correct answer to the question. The house has 3 stories. But as I said, I'm not trained to read blueprints and I've probably gotten my self just close enough to right to be completely wrong.

Count on a disbarred lawyer / developer to finesse the plain meanings of words to suit his desire.

lol This video caused some great debate around my house! I showed the shot of the blueprint (without the answer) to 2 of my sons then I posed the question to my wife (who has been a school board member during 2 building expansion projects). She's the only one (including me) who got it right - "Well, OF COURSE, that bottom area isn't a story!..."

IMO any space that is livable and/or more than 12'x12'x7' with the intent of occupancy should be considered a story/floor, all in all, the only reason we worry about a story is weight... so if the square footage comes over to enough to equal more than a certain percentage of the roof it should be determined to be a story, if an area built into a larger area where the floor does not add support to the area above then it might get a pass as a story...

Yeah but how far across the plan view of a building does the mezzanine need to stretch before it becomes sufficient to turn the single storey into two storeys?(according to the regulations)... Seems rather arbitrary, and I'd rather that storey was defined by mass of building materials between two floors

nice, thanks for this insight

The story, but not the whole story.

As a Florida transplant for almost 30 years, information you put out is very interesting. I have met a lot of people that worked in construction all over Florida in the 1970's-1980's . The stories they told, Florida is lucky more buildings have not collapsed, yet.

EDIT: Most of my questions are answered by section 505 that was mentioned in the video. There are limits on the size of a mezzanine. ORIGINAL: When does a mezzanine stop being a mezzanine? In your case the mezzanine was around a third of the 2nd story. What if it was 1/2 or 3/4 of the story? What if there were only one foot open from floor to ceiling on the left? Would that still be the second story with a mezzanine? Also, does height have anything baring on a story? If each story was 25 feet, a 10 story building would be much taller than a 13 story building with normal heights. So the reason for all of these questions is can I build a 12 story building with 25 foot stories, with a mezzanine covering 90% of each story if the code limits me to 12 stories? Also, can I build the same with 3 stories and not be subject to the new laws? Normally a 3 story building would be around 42 feet. But I could have essentially 6 floors and be 75 feet tall. Lastly, how many mezzanines can a story have? If these are not already addressed in the laws, a developer may get around the intent. And then again, maybe all of this is already covered.

excellent content

Ah, the ins and outs of the building industry. Most interesting. Thanks for the upload.

I have paused the video as Josh suggested to offer my answer to the question, "How many stories is this building?" My immediate answer is it is a four story building. However, nuances suggest it will be judged a two story structure as the parking/stilts/storage/basement will be judged to be below grade, and thus not counted. Likely the loft/mezzanine will also be exempted out as the measure to rafter from main floor will be the critical judgement. If I am correct in my hypothesis, and the rules are so full of holes a four story structure is magically counted as a two story structure, it would seem the Florida legislature must amend the code to require all structural floors to be counted. I will also note at this point we do not know if this is a single home structure. If the structure continues in a townhouse like configuration, with units sharing walls, it may trigger the condo rules. This may or may not offer clarity. It may simply make the judgments more confusing. Let's return to the video now and see what happens!

I live in Denver and managed properties. You just answered so many questions about while so many 5 story building have a penthouses added. These penthouses go above the elevator. In some cases the penthouse is a non necessary patch on top of the building. These penthouses really have no reason to be a part of the building. This makes me a little sick inside.

3 story building. Crap, that mezzanine definition screwed me :D. You are a wonderful educator.

Oh, in that case, Josh, it’s got an e in it - storey. 😍 Not entirely your fault when everything else you showed us also has “story”. Plural: storeys.

Very interesting and informative.

What happens in the case of the traditional US split level or 1 1/2 story house. There is a ground level, usually level with the garage which is half the footprint of the building and has a second level of rooms above it. And adjacent to that is a single level raised above the ground level by 3-4 feet. From the ground level you go up a half-story height staircase to the middle level, and from there up another 1/2 story staircase to the top level. You could argue that it is two story, because of the two levels in the portion that starts at ground level. but calling the single level adjacent to it a mezzanine does not make sense because there is no floor directly below or above it. A more extreme example is the courthouse building in Palo Alto, CA. It can be looked at as two "towers", the Office tower and the Courtroom tower. They are part of a single structure, with a full depth (front to back) core between them containing elevators. Each elevator has a door on each side, and the elevator starts at the basement of the courthouse tower, stops at the ground floor of the office tower, the ground floor of the Courtroom tower, and so on to the last stop at the fourth floor of the Courtroom tower. To make sense of this, you probably need to add an additional section to the definition to state that if the building is composed of more than one vertical unit, with or without an offset, the story count of the building is the highest story count of the individual vertical units. In this case, I would call it a five story building (because of the basement on one side.)

Great video .

Great Video.

Thanks Josh 😎

It would seem that load bearing should also b considered. That weight on top of that first space is suspended whether 2 ft or 9 feet. Isn’t that the original intent of what a story is?

Cool! Thank you.

14th floor, no one names it 13th or it will have bad luck...