Milton Gregory "Greg" Grew, AIA is CEO of Grew Design, Inc and Grew Construction, LLC in Woodbury, CT. Greg is a licensed architect, building official, and contractor with over 20 years designing/building residential, commercial and institutional building projects. www.GrewDesign.com
FIRE SAFETY OF ENGINEERED LUMBER OR I-JOISTS
May 12th, 2010 by Milton Grew
I had a most unusual experience occur recently with a local building inspector that reminded me to question what I do as an architect from time to time.
I have been involved in a substantial 7-figure renovation of a house in Westchester Country, NY. During construction it was revealed that a section of the house’s second floor joists would have to be replaced. We decided to replace the old 2×8 joists with I-joists (http://www.apawood.org/level_b.cfm?content=prd_joi_main), which can support longer spans. This allowed us to open up the first floor and remove some walls and posts. It was a great solution to the problem.
Then the local building inspector got into it. Upon completing the framing inspection, he asked the builder if they were going to install the fireresistance rated drywall for the ceiling under the I-joists. The builder said he was planning to use regular ½ inch drywall and knew about nothing else. Next the builder calls me. Being quite familiar with the NY State Residential Building Code, I confidently tell him not to worry about because using fireresistance rated drywall is not required in the code. Just to make sure I am correct, I check the state code and the local ordinances. I find nothing.
So I send the building inspector an email asking him about his request and telling him I know there is no such code requirement. In part, he writes back:
“Whenever we receive plans showing TJI’s it is our policy to ask for 5/8″ Fire Code Rock covering on all ceilings. It would be a shame to have this residence receive a lesser standard of fire protection than any other in Town…”
Now I am ticked off! We go back and forth and the bottom line is that we are going to have to put in the 5/8” fireresistant drywall ceiling or else the building inspector will find some violation to cite at the job for a fine of $2,500! I consult with the builder and homeowner and we agree to comply with his demand to keep the job moving. However, this matter keeps nagging at me and I finially decide to do my own research in the area of fire safety of I-joists and to send the building inspector an email with my conclusions and criticisms of his way of working. Here is what I wrote to him:
“Dear Mr. [Building Inspector]:
Based on your strong opinion regarding the lessened fire safety of I-joists, I have been doing more of my own research. A balanced approach seems to be that regular gypsum board cover on I-joist floors is a reasonable cover which gives occupants the time needed to egress a single family house. It is clear that uncovered I-joists are worthless in a fire. The IBC assigns 15 minutes of additional fire endurance to 1/2″ regular gyp bd and 25 minutes for 1/2″ type x. Various reports and sources make it clear that even noncombustible members behave unpredictably in a fire situation and laboratory results are never like the real situation. Sometimes materials behave better than expected, sometimes worse. It seems, until more definitive results are published and there is more agreement in the industry, it would be wiser to concentrate on regular drywall cover and inspecting for proper bridging, fireblocking, and smoke/heat detection.
Fire reports indicate that a very small percentage of the deaths are attributed to structure collapse and then not all of those due to I-joists. If you were really intent on preserving lives to a higher degree than everyone else you would have gotten the town to enact an ordinance to require residential fire sprinklers like in New Castle, not some unofficial policy like 5/8″ type x when the science isn’t really clear that there is any demonstrable benefit. The science and empirical evidence is clear when it comes to the benefit of sprinklers.
Short of that I was disturbed by your insinuation that I, as an architect, and every other town in NY and all other jurisdictions that don’t have your policy somehow care less about people’s lives. Because you are a building official in NY and not CT you might not be aware that I am a licensed CT building official besides architect. Since I took the exam about 5 years ago I still hold the record for the highest score in the state and I keep up my license with the 90-hours/3 years continuing education besides the continuing education I pursue for my architectural practice. The only reason I bothered to take the exam, become a licensed building official, is that I do care about codes and standards and their application and enforcement in building design and construction. I do care about the lives of my clients, contrary to your assertion.
What I find disturbing is when code officials take it upon themselves to create their own little parochial “policies”. It is the same as the old fashioned “that’s not the way we do it in my town”. It goes contrary to the entire reason statewide codes and national model codes and standards have been developed. If you feel strongly about an issue or you think the science is all on your side, would it not be better to push for a statewide change or at the ICC level? Or is the argument not strong enough to be accepted by code enforcers at large? Frankly, why stop at just the ceiling cover on I-joists? There are so many things that could be better in houses than the minimums required in the codes. And certainly some others would enhance public health, safety and welfare, too.
I have provided in the PDF attachment and items below some of the available information on the subject that make it clear that your 5/8″ type x “policy” is not the panacea you may think. I have attached the latest overview report from NFPA (of which I am also a member). It is very revealing because it does not list light construction or I-joists as in issue in resulting deaths or injuries from fires. In fact it indicates that fires have gone down about 50% in the last 25 years. How can that be so at the same time that framing is getting lighter and we are using more engineered lumber and trusses and everyone except [your town] is using 1/2″ regular gypsum board? Could it be that what is more important is the increased awareness and enforcement of blocking, penetration seals, and detection? If you have more definitive information I hope you will share it with me so I can be more educated on the subject. In the meantime, our contractor at [Address withheld] Rd this weekend is either adding the 1/2″ type x to the reg layer already on, or his removing that and putting up new 5/8″ type x. It depends on how his light trims work out. I thank you for raising the issue so that I would could pursue investigating it myself. I am not quite so convinced as you are of your position but I don’t think that means I care less about people’s safety.“
I received no initial reply from the building inspector and I figured I had burned my bridges with him. A short time later I came across an article in SBC Magazine about a fire test demonstration that seemed favorable to engineered lumber and I sent it to him. You can read about it here:
The building inspector replied as follows:
“Thank you for sending along the article. It has done little to sell me on the virtues of Trusses in general. This test has been widely discussed in the fire service. Before too much weight is given to this it is important to recognize who is putting on this show. The Manufactures and distributors of Trusses who derive their lively hood from selling this product to the general public have a different agenda than those of us in Code Enforcement and the Fire Service. The article states that a large number of the skeptics in the audience were older Veteran Firefighters and that the New members of the departments easily accepted the results. This does not surprise me because you learn from what you see, if all you have experienced from truss construction is this demonstration then it is easy to believe that they are safe. If however like me you have in excess of 25 years of hands on experience you tend to believe what you see and that is a dramatic departure from what the Industry wants you to believe. I strongly recommend reviewing current and archive articles from Fire Engineering Magazine or any Publication from John Mittendorf. retired Chief of the Los Angles Fire Department regarding Truss Construction. The important thing to remember is that those of us in the Fire Services are not trying to sell you anything and in many cases it is our lives that are put in jeopardy by these products.”
Now, this issue has made me start thinking about the industry’s quick change over to engineered lumber and whether or not the fire safety issues have been thoroughly investigated. So if any of you who had the patience and interest to read this have more information or sources for me to review please send them on to me. I would love to know what other construction-related professionals think of the fire safety considerations around engineered lumber, especially I-joists.