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Our Building Codes - Good, Bad, or Ugly?
13

Our Building Codes - Good, Bad, or Ugly?

Our Building Codes - Good, Bad, or Ugly?

(OP)
What do YOU think of our building codes, the IBC and IRC?

I've been publicly critical of the International Codes over the years. Well, someone at the ICC finally saw one of my articles and lashed back with a letter to the editor:


This letter is in response to a two-part piece I wrote concerning minimum rebar requirements in foundations. Here are the two articles:

Part 1, Minimum Rebar In Footings, from Structural Engineer Magazine, January, 2013

Part 2, Minimum Rebar In Foundation Walls, from Structural Engineer Magazine, March, 2013


Of course the ICC would disagree with my opinion that their publications are convoluted and confusing. But to suggest that I be banned from voicing that opinion in the future is downright un-American.

How do you feel about the IBC and IRC?

* Are they user-friendly?
* Do they produce consistent results from user to user?
* Can you find what you're looking for easily and quickly?

I'll post the results from this poll on my blog at BuildersEngineer.com

Thanks for you time.

RE: Our Building Codes - Good, Bad, or Ugly?

I haven't used the IBC and IRC but it seems they share many similarities with the National Building Code in Canada which includes Part 9 - "Housing and Small Buildings".

User-friendly? Not really.

Consistent results? Not really. Others sometimes interpret the code differently than I.

I can't always find what I want easily or quickly, but when it comes to minimal reinforcement in concrete, I tend to use engineering judgment (which results in lack of consistency amongst engineers).

To avoid confusion over the term "plain concrete", perhaps we should be using either "unreinforced" or "lightly reinforced" concrete. Your "naked" concrete is good too.

BA

RE: Our Building Codes - Good, Bad, or Ugly?

As the "International" codes are not international, I can't comment. The ACI Code is more international, as it is the basis for many concrete codes worldwide. It is not always simple to interpret, and I still prefer the 1963 version. As to reinforcement, I have often used unreinforced footings, but never unreinforced walls.

That last paragraph in Mr. Bracken's letter is insulting to you, and is demeaning of his position.

RE: Our Building Codes - Good, Bad, or Ugly?

It seems like plain concrete specifically is an area that no one wants to touch.

I recently gave a similar presentation to my company to try and simplify the various requirements between IBC, IRC, ACI 318, and ACI 332.

I typically use 0.0018bh for footings under bending, and .0014bh for lightly loaded footings without bending. Walls designed under IBC get a minimum of 0.002 horizontal and 0.0012 for vertical. IRC design is a whole other story, still I prefer to use the IBC rules, but this can add up for a whole neighborhood and doesn't keep the cheapskate homebuilders happy. I'll use plain concrete footings where I can, but I still like "some" reinforcing.

The gray area occurs where engineers define "some" reinforcing. For a deep trench footing (say, 18"x24"), I'll put (2)#4s. I'll see other guys using (3)#5s top and bottom.

Unclear? No. I'd say technical. It's kind of like the tax code. If it was easy, you wouldn't have to hire a professional.

Does it produce repetitive results? No. But there are many different interpretations of the code and various regional practices. A Texas slab is different than a Virginia slab is different than a Vermont slab.

I can find the information easily because I know where to look. It takes some time to get comfortable with the code, though.

RE: Our Building Codes - Good, Bad, or Ugly?

In answer to your three questions, from over 40 years of dealing with building codes that have consistently maintained a drive over the years to become more and more complex and cumbersome, as well as expensive,

No, No, and No.

The famous "Appendix D" is the perfect example.

Mike McCann
MMC Engineering

RE: Our Building Codes - Good, Bad, or Ugly?

BuildersEngineer,

Hear, hear! Thank you for being brave enough to address this very serious issue. The complexity of the codes is causing them to reach the point where people are starting to ignore them, not because they want to, mind you, but, rather, because they have businesses to run and deadlines to meet. Not everyone has time to unravel all the requirements required to figure out the code-writers' intent. So then they turn in desperation to magic black-box software that churns out results for them, hoping that it's correct. That doesn't make it right, but it is reality.

There is much more I could say but for now I'll try to confine myself to the following two additional points:

1. Your critic ascribed to you a motive of satire; what satire? I didn't see any; I saw direct criticism.

2. Your critic claimed that the code was not byzantine but also wrote that his organization teaches classes on how to navigate it. That's quite a self-contradicting position to hold.

RE: Our Building Codes - Good, Bad, or Ugly?

Yes...the building codes are confusing and interpretable in different directions. I find Bill Brackens comments to be insulting and incorrect. As a structural engineer in Florida, he knows the Florida Building Code has so many inconsistencies and erroneous statements that it is, at times, incomprehensible. Multiple examples are available that show requirements in the High Velocity Hurricane Zone (HVHZ)are different than for other areas in Florida, yet they have no relationship whatsoever to wind. Another fine example....Exposure D as defined in ASCE 7 is no longer applicable in the Florida Building Code; however, it is clearly applicable to numerous barrier island conditions in Florida where the fetch is a mile or more. The Florida Building Code is a direct derivative of the IBC. It sucks.

I get thorougly pissed at the vague and wishy-washy provisions of the building code. The lack of definition is horrible. The loopholes contained in the code allow defective construction.

Don't get me started.

RE: Our Building Codes - Good, Bad, or Ugly?

I recall not particularly liking the article, but I don't see the point (and still don't) in replying in particular to the magazine. My appreciation for SE magazine has dwindled over the years from the original (from what proved to be a false nadir). Structure has material that is online, available "free" and reasonably succinct and to the point and more on target. SE Mag fixates on BIM, green, sustainability, IPD, and other irrelevancies (in my opinion) and is too fixated on glossy versus technical.

That said, I can't recall exactly what I didn't like about your article, but, unlike the average Weingart editorial, I don't recall rolling my eyes or trying not to gag.

As to the code being straight forward? No, and less and less now that is it losing content and punting to the referenced document. Let alone the poor level of achievement when it comes to ICC marking revisions of material THEY CONTROL, which is pretty spotty, and further, the quality of revisions is usually dismal as well, changing a "which" to a "that" would be a classic (and pandemic) example, along with the roughly five thousand revision marks in Chapter 21 because the Masonry people rearranged their acronyms (WHY?).

I guess you can call it a victory he didn't open an investigation into your competency (he merely draws the line at maligning your character and impugning your reputation). Now a competency inquest, that would be inconvenient. Honestly, technical publications and humor don't mix (it didn't occur to me you were being jocular).

No offense intended. I don't find plain concrete that dismaying, but as an engineer, I'm not all that interested in the subject as it's my discretion to put reinforcement in, and if it's not put it, it's a violation on the builders part. Now, were I a builder, the interest would be there.

--Brian.

RE: Our Building Codes - Good, Bad, or Ugly?

Ron:

Hurricanes suck too, but you still have to deal with them. banghead

I have had the feeling for years, that the code changes are driven, not by safety, but by economics, getting closer and closer to the line of failure, so that any mistake in design become more life threatening due to the lack of available redundancy. I have seen this in comparing the requirements of the OSSC (Oregon Structural Specialty Code) with TIA 222-G.

I also feel that the code is just an educated guess. No one can predict exactly what will happen in any given event with a 100% degree of certainty. It all boils down to risk management, and, at times, ends up being a crap shoot. In any testing scenario, how do you know for certain that all the possible scenarios nature can contrive have been considered? You don't. You can only make an educated guess based on sometimes very limited experience and records. Nature has unlimited experience.

So, I set any guidelines from any code as a bare minimum and use my best judgement to solve the problem as I see it, not the ICC.

Mike McCann
MMC Engineering

RE: Our Building Codes - Good, Bad, or Ugly?

The codes should be about 5 pages long and only contain headings and references to suggested manuals and research. Let the engineer choose the research and theory that he would like to follow and apply to his design. It would be interesting to see what happens fi there were no more cookbooks. The question then changes from "does this meet code?" to "is this safe?".

EIT
www.HowToEngineer.com

RE: Our Building Codes - Good, Bad, or Ugly?

Mike...yup!

Codes are political more than technical. Even the model codes (IBC) are political.

The IBC is a "model code". It is a guideline upon which the real code should be based. Because of laziness, that usually doesn't happen. Most jurisdictions adopt a model code without revision. This is the predominate method of adopting the IBC. Some jurisdictions use the "model code" as the basis for their building code, making revisions to supposedly suit the needs of the locale. This is the approach that Florida and a few other states attempt. The Florida abomination is no better than the model code and only addresses a few of the necessary inclinations that might be somewhat unique to Florida. In that process, there are few if any improvements over the "model code".

RE: Our Building Codes - Good, Bad, or Ugly?

I was interested in the Editor's note at the end of Part 2:

"Clarification of building code requirements, if necessary, can be readily obtained by contacting the building code authority having jurisdiction"

I don't work in the USA, but is that how it works? "Readily obtained", really?

Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/

RE: Our Building Codes - Good, Bad, or Ugly?

My experience dealing with the building codes is limited to very specific areas (tanks, vessels, & similar.) I would agree that the codes in general are very lacking in those areas, and it has always seemed to me that they must have been written by people that never actually designed any of those items. I could go into some detail, but time & space don't permit it. However, on the bright side, I find that apparently nobody else knows how to interpret those sections either, so whatever interpretation you apply, nobody ever dares question it and it's good.

A couple items that come to mind, though...
You'll have Section 1.2.4.5.6.d.F(g)-Subsection H, titled "Widgets". Then the first sentence reads "Widgets shall conform to this section." Now wait just a second. What does that really tell you? Didn't the title already say that? You just paid a nickle for that sentence and it's absolutely meaningless.

And just exactly what does that standard apply to? That comes back to definitions. So you look up the definition of "structure" and it says "that which is built". IE, houses are structures. But then, so are cars, bicycles, steam engines, ball bearings, computers, hammers, hamburgers, wristwatches... Good thing they narrowed it down for me or I might have been confused.

RE: Our Building Codes - Good, Bad, or Ugly?

By the way, I just went back and read your two articles. Very telling is that the response letter there did not come back and say, "Oh, you're required to have rebar in Circumstance X but not in Circumstance Y". IE, he criticized your interpretation while declining to offer any constructive input as to what the codes actually meant.

The little note added at the end of the article is interesting, too, and indicates that code interpretation is available from local building officials. But if I remember correctly, ICBO offered code interpretations to building officials, but not to actual design engineers.

RE: Our Building Codes - Good, Bad, or Ugly?

One correction...the letter by Mr Bracken referred only to the first part of the article, and was published in the March issue, concurrently with the second part of the article. So more to come?

RE: Our Building Codes - Good, Bad, or Ugly?

I'll go against the prevailing winds here and suggest the building codes do a fairly good job considering what they are, and that a lot of work clearly goes into making them usable.

Building codes have a REALLY hard job to do. Not only do they need to reflect the most accurate research in engineering design , but they need to do it in persnickety legal language so it can carry the force of law. I'm not a lawyer, but certainly the situation here is far better than with any other sort of laws, which require mountains of case history and argument to interpret. It would be really easy for them to be the most difficult to understand documents in existence, but they're often usable enough to be the only reference an engineer has for a particular subject, which I think says a lot.

As far as being more and more complex, that's true, but I'm not sure how much blame the code deserves for it. ASCE's wind provisions are certainly tedious to deal with, but they're also a lot more accurate than simply using, say, 30 psf everywhere (which is what you could use 100 years ago, give or take).

And as far as usability is concerned, there's lots and lots of things that are done. The inclusion of simplified calculation procedures where more difficult ones aren't warranted. The marking of where a section has changed from a previous section. Deliberately laying out charts and graphs so the most frequently used information is visible. The inclusion of commentary. Again, this is far far better than other sorts of legal documents.

Codes are obviously a far cry from perfect, and often ARE difficult to understand, and SHOULD be improved and made better. But I think they do a reasonably good job, all things considered.

Brian C Potter, PE
http://simplesupports.wordpress.com

RE: Our Building Codes - Good, Bad, or Ugly?

I remember reading the article and thinking, wow, if people spent near as much time and effort working on committees to improve the building codes as they do griping about them we'd all be in a much better position.

RE: Our Building Codes - Good, Bad, or Ugly?

Committees...therein lies the problem.

BA

RE: Our Building Codes - Good, Bad, or Ugly?

WillisV, you have a point, however that involvement is not always available to employees.

RE: Our Building Codes - Good, Bad, or Ugly?

Willis, that wasn't a gripe, was it?

On a serious note, the only people who have the time or opportunity to work on building code committees are academicians and people who work for large engineering firms. People with small firms, that is, businesses that they run, don't have the time or opportunity to do so. The best way they (we) can affect change is to voice our concerns to the relevant parties and amongst peers as is, for example, being done right here. In other words, we're not griping, we're trying to be constructive using the most accessible (and only practical) tool at our disposal.

Brian, your point was well-made and well-taken, but please remember that for lawyers legal language is their product. It isn't for engineers. For us it's that which we have to comply with. We have a separate product, namely, constructable building documents that we have to produce to get paid. If the legal profession was complaining about having to understand the mechanics of supporting the building in which their office was located before they were allowed to draft a will...well, then they'd know how some of us feel, perhaps.

RE: Our Building Codes - Good, Bad, or Ugly?

Having actually submitted a code change proposal or two (both of which died) attempting to simplify how a mathematical expression was presented, and seeking to clarify the units (to me a square foot to the 1/2 power is a real puzzler), it does not take that much time to do a code change proposal. That's a weak excuse. I work for a small company, I can spare an hour. You have enough time to troll the internet message boards for engineering, you have enough time to do a code change proposal.

The problem is the yield - an hour for nothing.

We'll see what happens to my latest - an attempt to get a minimum connection in IBC into IRC (or vice versa, I forget).

Code users are in the best position to improve the code, as they are actually using it. Submit them when they arise.

If you follow the proposed changes, you'll notice there is one person who seems to submit about thirty code change proposals a cycle, all of which are of little value.

And then we have the great sprinkler lie - where it was approved despite "will not change the cost of construction" box being checked (to my recollection, I may be wrong).

--Brian.

RE: Our Building Codes - Good, Bad, or Ugly?

So let me get this straight: submitting something that was completely ignored and changed nothing was worth an hour of your time?

Besides, if I could change regulations with a simple letter we'd have a flat tax in short order.0

And I don't consider my participation here "trolling", thank you very much. It's a forum though which to exchange ideas with, and get help from, peers, and to learn from online mentors. Hardly a waste of time, in contrast, I would suggest, to your proffered submission to a code-regulating body that publicly asked a profession journal to stifle dissent, reminiscent of any tin-pot dictatorship throughout history.

RE: Our Building Codes - Good, Bad, or Ugly?

Archie,
The letter was not from the code body. It was from an engineer who used his connections to the ICC and the Florida Board to demonstrate his importance. Whether or not those bodies knew of his action, I don't know.

RE: Our Building Codes - Good, Bad, or Ugly?

Archie - read what I wrote, please.

RE: Our Building Codes - Good, Bad, or Ugly?

One other minor snafu is that any revisions made will go in an upcoming edition, if incorporated, whereas the problem may be in an older version (ie, ASCE 7-98). So whatever gobbledygook was in the old version is in there to stay and you're stuck with it.

RE: Our Building Codes - Good, Bad, or Ugly?

I was on a code writing committee several years ago and I can tell you the guys writing the code, including myself, often forget that the users of the code don't have the advantage of sitting in the room with the other code writers and listening to the explanation of where they are trying to go with a certain paragraph. I mean after a 30 minute discussion everybody agrees that its clear and then they move on. How can they really expect some poor schmuck all by himself with no one to get feedback from to glean what they intended?

RE: Our Building Codes - Good, Bad, or Ugly?

I think the problem is that they are working very hard at trying to look like they are doing something.

Take the load combinations changes for wind from 2009 IBC to 2012 IBC. Wind in the Load combinations using strength design or load and resistance factor design went from a 1.6W to 1.0W. In the Load combinations using allowable stress design wind went from W to 0.6W. Guess what 1/1.6=0.625 so they merely changed the factor from one set of equations to another set of equations.

The important factor is removed, but now there are three wind maps.
Looking at the equations in the 2009 IBC you have p<net> = q<s>K<z>C<net>[IK<zt>] where q<s> = 0.00256V^2 Section 1609.6.3 and Table 1609.6.2(1) for an equation of p<net> = 0.00256V^2K<z>C<net>[IK<zt>]. The 2012 IBC you have p<net> = 0.00256V^2K<z>C<net>K<zt>. Since the I value is gone and the V values change (see 2009 IBC figure 6-1 and 2012 IBC figures 26.5-1A, 1B & 1C).
For the difference Categories you have
Cat. _______ 2009 IBC V^2(I) ___ vs _____ 2012 IBC (0.6)V^2
____________________________________ (at 0.6W with all the other factors being the same.)
I ________ 90^2(0.87) = 7047 ___ > _____ 105^2(0.6) = 6615
II _______ 90^2(1.0) = 8100 ____ > _____ 115^2(0.6) = 7935
III & IV __ 90^2(1.15) = 9315 ___ > ______ 120^290.6) = 8646

For a minor decrease in the wind loads.

Looking the ASCE 7-05 (as referenced in the 2009 IBC) to the ASCE 7-10 (as referenced in the 2012 IBC) you will see the same thing happening.

Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.

RE: Our Building Codes - Good, Bad, or Ugly?

User Friendly: So-so
Consistent Results: No
Easy to navigate: Yes, with experience, which is probably the same for Law, Medicine, running a McDonalds, etc, etc.

Regarding question 2, having observed and been involved in contentious disputes, it has amazed me how two equally experienced, qualified “experts”, can thoroughly, and convincingly argue different interpretations of the code and how it impacted a particular design/construction flaw or failure. What this means, I’m not entirely sure, but it does speak to consistency and repeatability.

IC

RE: Our Building Codes - Good, Bad, or Ugly?

woodman88-

Disregarding all the other reasons for the wind provision changes (one of which being it more accurately reflects what the wind speed actually is), a "small" reduction in wind loads is nothing to sneeze at. Even considering the added cost of extra engineering time and re-writing software, it probably amounts of a savings of millions of dollars over the course of the thousands of buildings that will be built under those provisions.

Brian C Potter, PE
http://simplesupports.wordpress.com

RE: Our Building Codes - Good, Bad, or Ugly?

2
I disagree, briancpotter.

Your position assumes structural design involves "continuous" functions. I'd say design is "discrete". Let me explain: If you get say, a 5% reduction in wind loads (and that is an the high end of what the change is for the vast majority of the country), you are not suddenly going to begin spacing rebar in walls at 11.4 in on center instead of 12" o.c. You are not going to start using 2x4's instead of 2x6's, etc. Or changing the spacing of wall studs from 16" to 15.2".

I do understand that the committees are genuinely trying to reflect the most accurate research. I think, however, that they have begun missing the forest for the trees. The complexity of the codes primarily affects the engineer (and architect); not owners or contractors. The onus is on us to make sure we muscle through all the minutiae of every little exception, change, and trigger, the end result being designs not all that different from designs of 20 years ago.

Engineering, unfortunately, is becoming a commodity. In an environment of ever increasing competition, the increase in code complexity is straining either the profitability or the adherence to the newer codes in many firms.

I'm not suggesting we stop research of stop updating codes. But I think we should be a bit more cautious and deliberate with changes. Before we update a provision for a 2% lower load, let's think about ROI for the engineer, not just the contractor.

RE: Our Building Codes - Good, Bad, or Ugly?

lexpatrie, I apologize, I was out of line.

Regarding the codes, I know I value the old code and reference books on my shelves. They weren't perfect, of course, but I have an easier time understanding them.

frv, I think you and Brian might be getting at the same point in a different way. That is, a 5% reduction might have value for, say, a truss or bar joist manufacturer, but for most practicing engineers it is of little to no value and might be a detriment. I know I have no interest in skinnying down the design to it's absolute bare minimum, and even less interest in spending hours to figure out what that bare minimum might be.

RE: Our Building Codes - Good, Bad, or Ugly?

6
Codes should not be an end in themselves, they should be as clean and as simple as possible, a means to an end, and that is safe infrastructure design. Code writing and publishing and the univ. research that feeds it should not be a larger and larger cottage industry to the detriment of actually getting the infrastructure designed and built with public health and safety and the economic use of materials in mind. We don’t need new editions of codes every three years, and we don’t need ref. codes all being out of synchronization with each other either. Nobody can begin to keep up with this crap any more and do his job well, in terms of the actual design production and quality of design. We are not really designing safer or better structure than we did thirty years ago, but we are working twice as hard to do it. Just look at the questions we get here on E-Tips. Half the time the OP’er. has no idea of the big picture, or what he is really designing but he has started a big debate about whether R-sub-bvq should be multiplied by 1.57 or 1.59 because it is a Thursday and it’s raining; and no one really even knows what Rbvq is or where it came from.

Throughout my career, and a good share of that has been spent critiquing bldg. and other structure failures; I haven’t seen many instances where some fine point (an elaborate code improvement?) was missed and caused the problem. But, I have seen plenty of instances where sheer stupidity, lack of fundamental understanding of how the structure works, or out and out incompetence has caused the ultimate problem. And, I don’t think we can ever codify those things out of the equation. But, we can police them out, by not allowing incompetents to do this work. Good Structural Engineering and design has always required good engineering experience and judgement, and this has always involved learning under the tutelage of an experienced engineer, not a more complexified, unreadable, uninterpretable, gooder code edition at an exorbitant price. When I read bldg. codes these days, I don’t have enough fingers, triangles and scales to mark the pages as I refer back, and back further, to other subsections, other ref. documents, etc. You soon get lost in the minutia and forget what you are really designing. We are so busy worrying that we may have missed a small subsection item back on page 4728, and that we might get sued for this, that we can’t see that this is just a crappy detail which won’t work even if designed to the nat’s a$$.

We do need good people, practical, practicing engineers on these committees, or this whole code thing will continue going down the tubes. The academic types will keep turning out this trivial research, just as they are turning out unqualified young graduates, but otherwise, 85% of this research does not need to find its way into a new printing of the codes next week. Good engineers used to read the tech. journals and bring some of the research into their designs once it had been peer reviewed and discussed, and that didn’t need a new $300 per copy printing of the codes. If you want to do something constructive, go to you AHJ or your State legislators and explain to them that they are not getting better infrastructure by adopting the next edition of the IBC. Let us learn to use the one we now have efficiently and effectively. You want us stamping these designs, so let us make wise use of materials and current knowledge without hampering us with a newer, even better?, bunch of indecipherable b.s. Let the ICC sit with unpurchased printings of the next couple editions of their codes and maybe they will slow down a bit, and get a bit more practical.

For all the intricate numbers the codes and FEA allow me to run, when all’s said and done, I can’t find a W24x134.35 beam. So, I’ll go to a W24x145, and now if I rerun my design I can space the beans at 20.833' instead of 20'. Then when I finally get the mill certs on those beams, I can redesign again, and space the beams at 21.002'. Oh, gosh, you mean I gotta move the columns and the footings too.

RE: Our Building Codes - Good, Bad, or Ugly?

...R-sub-bvq should be multiplied by 1.57 or 1.59 because it is a Thursday and it’s raining...

...I can’t find a W24x134.35 beam...

2thumbsup2thumbsup2thumbsup

RE: Our Building Codes - Good, Bad, or Ugly?

briancpotter -
You are missing my point. What I was addressing is the fact that they moved the 1.6 factor to the other side by using a 1/1.6 equivalent factor. Than upped the wind charts by 1.6. That is 1.6(90sq) = 114sq for the new V = 115.
Than got rid of the important factor by multiplying them to the wind chart values and created two other charts. So that we now three charts to look at inplace of the one chart that got multiplied by a factor.
When there is no reason (except to make changes so it appears that they are doing something) to move the factor or to make three wind charts just to remove the wind important factor. They could of merely adjusted the existing factors for the same results.
The same thing goes for the ASCE.

Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.

RE: Our Building Codes - Good, Bad, or Ugly?

woodman88,

If I recall, the change does reflect more accuracy in high-wind areas (hurricane-prone areas). But yes, the net result for those of us who practice anywhere other than the coast is that we now have added complexity for a net change of nearly nothing.

RE: Our Building Codes - Good, Bad, or Ugly?

frv -

I am sorry but more accuracy from a map of the USA printed on two 8.5” x 11” pages is a joke.
They could easily have added blowups of critical areas, like what was done for the seismic maps.
If they did need to make changes in special areas for the difference important factors, that could have been added also.
But what they did is an insult to engineers IMHO.

Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.

RE: Our Building Codes - Good, Bad, or Ugly?

I really really get ticked-off and frustrated anytime I have to plough thru these recent codes to the point that I use them less and less for all the reasons mentioned sofar and many more I could add.
I do not consider myself the sharpest tool in the shed, but , with over 35 yrs of real engr experience and two master"s degrees, I, all of a sudden, could not become that stupid that much of these recent codes make absolutely no logical sense to me...they have become more of a book-keeping exercise than a technical document, more of a hunt-and-peck endevour than a sound engineering presentation....the amount of time I have wasted and the time and cost to all the states, cities etc, implementing the newest version of these documents must run into the millions at a time when these entities are struggling to provide basic services to their population with all the cuts in budgets......but, complaining amongst ouselves will have no influence or change the course of events in the future...until there is a real monetary cost to the members of these commitees and the issueing organization for the amount of misdirected and unnecessary effort imposed on the practicing engineers and municipalities that have to implent them, then, I am afraid it is only going to get worse.....

RE: Our Building Codes - Good, Bad, or Ugly?

These building regulation codes are becoming more and more like the Tax Code.

RE: Our Building Codes - Good, Bad, or Ugly?

woodman88-

The increased accuracy has nothing to due with the size of the maps. It's because of the way occupancy (now risk) category works. The loads to be designed for are based on return period of a hurricane - the safer a building needs to be, the more certain you need to be that the loading won't be exceeded. Thus the hurricane return period for a normal office building is only 50 years, where for a power plant it's 1700 years. This is because a 0.1% (or whatever) chance of a hurricane destroying a building is an acceptable risk for a house, but not a power plant.

As Sandy just showed us, hurricanes have the possibility of hitting a very broad swath of the country. The longer your return period, the more places become "hurricane zones" and need to be designed for hurricane winds. Thus you can easily have two buildings in the exact same location where one needs to be designed for hurricane loads, and the other doesn't. It doesn't just affect a few special areas, but anywhere remotely close to the Atlantic/Gulf coast. The previous contours + importance factors didn't properly reflect this, and gave incorrect loads for high-occupancy category buildings, the exact buildings where getting the loads right is most important. That's why new wind contours were needed.

It's unfortunate that it requires a (slightly) more complex calculation, but it's not an unimportant change.

Brian C Potter, PE
http://simplesupports.wordpress.com

RE: Our Building Codes - Good, Bad, or Ugly?

My mistake, it looks like the primary cases affected are low-occupancy buildings. From the commentary:

"Multiple maps remove inconsistencies in the use
of importance factors that actually should vary
with location and between hurricane-prone and
nonhurricane-prone regions for Risk Category I
structures and acknowledge that the demarcation
between hurricane and nonhurricane winds change
with the recurrence interval."

Brian C Potter, PE
http://simplesupports.wordpress.com

RE: Our Building Codes - Good, Bad, or Ugly?

(OP)
Thanks, everyone for your thoughtful input.

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