A few years ago I was appointed to an International Code Council Committee tasked with converting FEMA P100 Vulnerability-Based Seismic Assessment and Retrofit of One- and Two-Family Dwellings into a building code which which was to be called ICC-1300 Vulnerability-Based Seismic Assessment and Retrofit of One- and Two-Family Dwellings. There are already 9 retrofit guidelines, all of which are hopelessly inadequate, and this was to be an improvement.
Retrofit guideline evolved from two separate branches. The first branch was started in 1994 with the publication of the Guidelines for Seismic Retrofitg of Existing Building (GSRB) and it is the source of most of the other guidelines. A new branch was started when the chairperson of that GSRB committee, Jim Russel, told me he wanted to start over from scratch and asked that I be a member of another committee that wrote Standard Plan A. FEMA P-1100 was a continuation of the Standard Plan A branch.
My sub-committee was to codify Chapter 4 of this guideline into a chapter of ICC-1300. I published these videos to show the other committee members why I believed certain changes should be made. My recommendations were for the most part ignored and I may have been completely off base. You can watch the videos and decide for yourself.
Our Worrisome Geology, Where It All Begins
This 2 minute video is not part of the critique of ICC-1300 but I thought it best to start there because this is the whole reason why this guideline was written.
The Complete History of Seismic Retrofit Guidelines From 1994 to Present
ICC-1300 is supposed to be the last of the seismic retrofit guidelines. This video looks at the history and evolution of seismic retrofit guidelines from the 1994 Guidelines for the Seismic Retrofit of Existing Buildings until FEMA P-1100 (soon to be ICC-1300).
There Is Still A Lot To Learn
In the cripple wall sub-committee meetings we looked at all aspects of Chapter 4 with the eye to root out any problems contractors might confront when trying to apply it. I was the only contractor on the committee (the rest were engineers) and had the perspective of a contractor. Contractors want a guideline to be affordable or no one will use it, it had to be practical so they can build it, and it had to be based on sound common sense engineering so it would perform effectively. I looked at it from all these viewpoints and concluded it was unaffordable, impractical, and, even though it was written by engineers, oftentimes the engineering unsound.
I pointed out approximately 100 changes I thought should be made to improve its affordability, practicality, and effectiveness. After lengthy discussions I don’t think I changed anyone’s mind. Even though I don’t feel like I was able to make any significant changes, I learned a lot in the process and you can too.
Why Is ICC-1300 Three Times as Expensive as Other Guidelines?
One thing that became clear from the outset was that the construction of a ICC 1300 retrofit would be extremely expensive. An ICC-1300 retrofit costs on average three times as much as a Standard Plan A retrofit based on this in-depth study. From my point of view this high cost doomed the guideline to extinction before it was even born.
Why Will ICC-1300 Make The Contractor and The Public Sick?
This was one area where I thought I would sway the other committee members because the change I recommended would protect the public from carcinogenic silica dust. Exposing the public to this carcinogen is unavoidable when performing a retrofit as prescribed by ICC-1300. The counter-argument to my concern was that “this is an OSHA concern and we are not part of OSHA”. Given ICC-1300 was written to protect the public this response was very odd to me. I believe this is the concern of anyone who does not want to get cancer.
Who Cares About Vent Holes?
After you drill about thirty zillion of them, you do! I think I scored a victory on this one. Drilling vent holes in plywood is a major pain in the ass and there is absolutely no reason for them. I think we even consulted a ventilation expert at and he also agreed ventilation holes made absolutely no sense.
What if it Won’t Be Affordable if You Follow the Code?
This is an interesting video. Committee members were in an uncomfortable position. Does one put public safety first by fudging on the building code a little bit to make a retrofit infinitely cheaper, or does one insist on following an insignificant section of the code (which is there to promote public safety) and make the retrofits unaffordable and thereby promote public safety. You can’t have it bolt ways.
Engineers like to draw perfect houses where the foundations are vertical, the framing is all 1 1/2″ wide, the mudsills are not embedded in concrete, and believe there is an army of little elves waiting to drag extremely heavy structural reinforcements under a house. This video looks at a framing modification that “is not according to code” which can save a homeowner several thousand dollars.
In a discussion with the chair of the cripple wall sub-committee, who is a Ph.D. engineer, he pointed out that if the code violation were allowed the floor might sink an inch or so if a piano were placed on top of the code-defiant floor framing, His position was that because it would be “against the code” my suggestion would be rejected. This is kind of funny when you remember almost nothing in the rest of the entire house. Watch the video and decide for yourself which option you would want to take.
Simpson FRFP Type B Connectors
Here we look at one application of the Simpson Type B Connector that results in a retrofit that is extremely expensive and the hardware components won’t even fit on any of the houses I have ever worked on.
Here we look at another ICC-1300 application of the Type B connector which in my opinion warrants removing this detail from the standard. Watch the video and decide for yourself.
A Retrofit Component No One Will Use
This video looks at one of the central pieces of hardware called the Type B Connector. In the real world it is the Simpson StrongTie FRFP. This video points out that contractors do not use FRFPs in seismic retrofit work because they were there is alternative hardware, primarily the Simpson URFP, that will do the same thing far cheaper and easier. My plea to the code committee was that this hardware is used so seldom that its place in the guideline and the construction details it contains should be replaced with something more relevant. The final decision against my objection was to keep it as is.
Protecting a House From Damage That Has Never Happens.
ICC-1300 Won’t Allow Staples. Are you sure?
This 2 minute video should convince you that stapled shear walls are a good idea.
This 20 minute video should convince you stapled shear walls are a REALLY good idea.
This 45 minute video was created with the help of the International Staple Tool and Nail Association (ISANTA) and looks at the use of staples from every possible angle.
This video fully convinced ISANTA but the ICC-1300 code committee voted down the use of staples because staples were not tested, even though there are many stapled shear wall capacity tables in the Special Design Provisions for Wind and Seismic. These tables, as well as the nailed shear wall capacity staples, are based on testing done by the American Plywood Association in APA Research Report 154 and APA Research Report 138. In short, there is plenty of testing to justify their use.
It was my believe that inclusion into the standard would promote public safety because according to APA Research Report 154 “the use of pneumatically driven staples showed that staples with a 7/16″ crown could be driven as close as 1″ o.c. without causing splitting, either at the time of driving or when the specimen was loaded in shear.” APA Research Report 154 explicitly emphasizes their usefulness in seismic retrofit work ” The use of staples as fasteners in shear walls is particularly useful to avoid any tendency to split the framing lumber in rehabilitation work where the lumber may be dry and existing fasteners may already be placed at minimum allowable spacing. “ In my own business I have found staples to be indispensable.
Watch the video and decide for yourself if staples are ok.
Balloon Framing: The Right Way and The Hard Way.
Balloon framing is a weird kind of framing that we see in houses built at the turn of the century and require very specialized retrofit techniques. ICC-1300 has a few details that address balloon framing. In this video I compare the ICC-1300 methods recommended by an engineer ICC-1300 to the methods contractors have developed after years of experience. The committee decided to use the methods recommended by an engineer. Watch the video and decide for yourself which is best.
An Easy Connection Made Difficult
This is a framing configuration we address all the time. ICC-1300 has one way of doing it and it will work but it is more labor intensive. I actually thought that when committee members looked at the method contractors use they would replace the current detail with the one contractors use. While I look in this detail one more time I noticed that the Type E Connector (this is the Simpson L90) contained a nail going through plywood into the lower top plate. Simpson does not have testing for this and strongly suggests that the nails used here should be 2 1/2″ long rather than the 1 1/2″ long specified in the catalog. The committee decided to use the detail with the L90. Watch the video and decide for yourself.
Destroying a Shear Wall To Make It Better.
This is a strange detail. ICC-1300 is set up so it is necessary to remove 1 linear feet of plywood so that a Type A -Simposn URFP- can be used. The objection was that the screws would be going through plywood. At the same type as shown in the previous video going though plywood is no problem. This detail was kept as is in ICC-1300. Watch the video and decide for yourself it that was a good decison.
What Planet Did This Detail Come From?
This detail is very revealing in that it shows how far removed the committee members were from the tools and techniques contractors use everyday. I advised the committee that because it reveals the extreme ignorance of the authors of ICC-1300 and it will lose the respect of contractors immediately.
It is however an important connection. See how contractors make it in literally 3 minutes opposed to the hours ICC-1300 demands. I think you will enjoy this video, I know I did. I need to laugh to keep from crying.
Doing It The Wrong Way
A critical connection in every retrofit is the connection between the plywood and the bolts. If this connection is weak the retrofit may fail. This video compares the method recommended by ICC-1300 and compares to three other methods contractors use on a daily basis. A letter from the leading shear wall shear wall testing laboratory in the world evaluated 4 different methods from the most preferred to the least preferred. The committee decided to use the least preferred. When this happened I realized one again that once something finds its way into a retrofit standard, no matter what it is, you can never get rid of it.
Wedge Anchors: Will They Work?
There are 3 types of bolts. Commonly known as wedge anchors, screw anchors, and epoxy anchors. ICC-1300 decided to disallow wedge anchors because one of its authors heard from one contractor that the wedges at the base of the wedge anchor breaks out the side of foundations when it is tightened. My company has literally installed tens of thousands of wedge anchors in the past 25 and this has never happened. For some reason 50,000 tests were no match for one incident of hearsay and wedge anchors remain banned. It should also be remembered that all the other guidelines preceding ICC-1300 allow wedge anchors. Somehow the members the ICC-1300 committee knew more than the scores of authors of the previous guidelines. Watch the video and decide for yourself if their decision makes sense.
Houses have a great deal of earthquake resistance even if they are not retrofitted. Government statistics show that at most 8% of the houses in the highest shaking zones will suffer enough damage to make them uninhabitable. When ICC-1300 was conceived it assumed that existing homes have zero earthquake resistance unless they are retrofitted. It is my opinion that ICC-1300 was installing far more retrofit components than it needed to and was thereby making it unaffordable. It is especially remarkable that it requires more retrofit components for houses with stucco siding than it does for houses with wood siding. This is in spite of empirical evidence to the contrary. Decide for yourself if it makes more sense to be ultra-careful and create something no one will use, or assume a house already has a lot of earthquake resistance and develop a standard that is affordable.
The earthquake resistance of plywood depends on the number of nails on the edges of the plywood. This nailing is called edge nailing. Tests showed that plywood nails spaced further apart did not have enough earthquake resistance to tell people about in the plywood strength tables in the building code. When Standard Plan A was revised (I was not there) the edge nailing was reduced from nailing being 4″ apart on the edges to 8″ apart on the edges. The retrofit guideline that came after Standard Plan A had the same problem. ICC 1300 almost had the same problem but fortunately it was changed so the nails on the edges from 2″ to 4″ apart. In this case the committee was convinced.
Many houses do not have top plates on the cripple walls that are parallel to the foundation. This is a very common problem. ICC-1300 developed what I believe is the most expensive convoluted way to address this problem. The purpose of this video was to show committee members far easier and cheaper methods that have been developed over the years by contractors. The committee decided to use the more expensive option. Watch the video and decided for yourself which method you think is best.
ICC-1300 promotes some unusual retrofit strategies. One of them being the installation of blocks that seemingly serve no purpose. I asked the committee to explain to me what their purpose was and they never gave me a logical answer. Maybe you can see one.
The committee was very worried about wood splitting because nails might split the framing. The building code cautions against nails being installed closer than 2″ apart, this video proves that nails can be 1″ apart on the same grain line. When reality contradicts theories the scientists on the ICC-1300 committee chose to follow theories. The future of any effective seismic retrofit guideline requires the merging of both theory and practice.
The Type A Connector (the Simpson URFP) is the most versatile and effective hardware in ICC-1300. The technique shown here that shows a block being used as a spacer was developed by me several years ago. I thought this detail was so important that I told the committee members that the detail was actually invented by another member of the committee and that they had simply told me about it. That is the only new detail that made its way into ICC-1300. Name and fame sometimes take precedence over public safety. I lied, and I really should not have done that, it was an experiment and it turned out as I thought it would.
Here is a general overview of the construction details found in FEMA P-1100.
Neither ICC-1300 or any of the other guidelines address the problem created by porches. Around 10% of the houses we work on have porches at the front that are supported at the front with complete foundations. Porches are a serious problem when it comes to effective seismic retrofits. Here you will see how to deal with this problem. The ICC-1300 committee decided to ignore this such that 10% of the retrofits that use ICC-1300 will be a waste of money.
Breaks in the upper top plates are a serous problem that must be addressed in every seismic retrofit. ICC 1300 addresses this with steel straps. In one of the code committee meetings I pointed out that steel straps were a very expensive way to accomplish this task compared to the one that only requires a few nails and was far less expensive. The code committee decided to us the most expensive and least effective option.
Bolts that are attached to the plywood are the only bolts that do anything. ICC 1300 does not account for this. This video was created to point out how critical this was. The ICC 1300 committee did its best to make sure the bolts were placed at plywood locations.
This is a shorter version of the video on the far right and was created so that I could make my point without taking up too much time from the other committee members.
This video shows an experiment on a shake table that proves the large number of very expensive holdowns were not necessary. This suggestion was not accepted by the rest of the committee.
ICC 1300 includes tie downs (which are the Simpson StrongTie HDU2 holdown). Their effectiveness relies on the strength of the concrete. This video proves the ICC-1300 committee did not notice this important fact. The committee decided it was too late to change things.
In these 3 ICC 1300 construction details the red arrows point to construction screws. They do not tell the size of the screws. Visually they look like 1/4″ self tapping Heavy Duty SDS screws made by Simpson Strong Tie.
Here you will learn how lag screws can be installed perfectly every time with a special jig.
Here you will see why it is impossible to install them without a jig.