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HomeMy WebLinkAboutCOM 0128.070 2010-2012From the office of: Timothy C. Rees Ag Services Hawaii CEO & Code Review Specialist P.O. Box 1787 Pahoa, HI 96778 Timrees5023 @aol.com 808 - 959 -5023 Press Release — Subject: Updating of Building Code Crn ""' CD This release is also being submitted as supplemental testimony to the Hawaii county county $ill 27dr.3 The Hawaii County Council was fully justified in reconsidering Bill 270 draft 3 (Building Code) for further amendments. Since the reconsideration, Public Works' latest interpretation of the sections relating to enhanced hurricane protection has changed extensively, completely modifying the effects of their proposed operation. Some background on the relevant factors is required. The International Codes have decreed all of Hawaii State as a windborne debris region (WBDR) simply by political designation without regard for coastal proximity or design basic wind speed. This is contrary to how all other so- defined (hurricane prone regions) are treated by the international codes. (see IBC 2006 , Definitions) Wind Borne Debris Region. Areas within hurricane prone regions within one mile of the coastal mean high water line where the basic wind speed is 110 miles per hour (49 m /s) or greater; or where the basic wind speed is equal to or greater than 120 miles per hour (54 m /s); or Hawaii. WBDR's represent the highest risk category for design purposes. For preliminary comparison purposes, Hawaii's basic wind speed is 105 miles per hour. There are two consequences to this WBDR designation. First, all openings in all new buildings (with minor exceptions) below 33 feet above grade must be protected with either very costly impact resistant glazing systems, very costly shutter systems, or, on residential buildings only approved ply board systems. The other consequence is that partially enclosed buildings of any use or occupancy are no longer allowed as a design option in WBDR's since about 2005. For quite some time now Hawaii County Public Works' representatives have been stating various versions of the following interpretations to the County Counsel and public record while discussing Bill 270 (video documentation available upon request): A. "A homeowner will have to choose one of three options: 1. Impact resistant glazing, or 2. Approved shutter protection, or Comm. No. t 2 '3 'I° Ref. To: Presentee GU A C i 1 Ref. Dote SEP g 1 2011 Page 1 of 5 3. Approved ply board protection, or A residential safe room. " B. "The safe room is not mandatory, it is only an option." C. "The safe room is only mandatory if you design a partially enclosed building- so the goal is not to design a partially enclosed building — otherwise it is mandated. But there are hardly any partially enclosed buildings — it almost never happens." Other than the safe room language and interpretations, the first 3 numbered options under "A" accurately depict how the international codes treat "protection of openings" in WBDR's. (IBC Section 1609.1.2) And as was stated earlier partially enclosed buildings are no longer allowed in WBDR's. Also note that the international codes neither mandate nor provide an option for safe rooms as an alternate means of protection of openings. They make no mention whatsoever of safe rooms. The safe room is an entirely maverick "Hawaii only" option or mandate as it relates to 1609.1.2. A safe room has nothing to do with exterior building envelope protection. The term "partially enclosed building" and its formula for determination has generated a lot of confusion even amongst engineers. It is perhaps best to think of it as say, a rectangular structure with an imbalanced window & opening distribution, such as a luxury beach house with most of the glass doors, windows, lanai openings, etc. on a long view /window wall and the other 3 sides with minimal openings. Many existing commercial and retail establishments can be considered partially enclosed under the ASCE 7 definition, and could therefore be disallowed as a new construction design option in Hawaii under the international codes (because of the WBDR designation again). The above comments are all based on a plain language reading of the codes. In marked contrast DPW's latest interpretation of the same language in Bill 270 as stated and verified at the public info meeting on Sept. 7, 2011 and again at Stakeholder meeting on Sept 16, 2011 with representation by Gary Chock, State Building Code Council (SBCC) member and author of many wind provisions; Warren Lee, Department of Public Works (DPW) Director; Brandon Gonzales, DPW Deputy Director; Jai Ho Cheng, DPW Building Division Chief Engineer and SBCC member; and Neil Erickson, DPW Senior plan reviewer is as follows: A. "Only partially enclosed residences require protection of openings under 1609.1.2" B. "The Protection of openings required on partially enclosed residences must be fulfilled by one of the following options: 1. Impact resistant glazing, or 2. Approved shutter systems, or 3. Approved ply board systems, or 4. Hawaii residential safe room." Page 2 of 5 C. "Safe rooms are never mandated, they are meant to be a low cost alternative, optional only." D. The "Protection of openings requirements of Bill 270 Draft 3 section 1609.1.2 are triggered only by residence "enclosure classification ", not wind speed or proximity to coast." Mr. Chock represented the State Building Code Council at the Sept 7, 2011 meeting. He is also the author or contributing author to many of the local and International Code provisions regarding wind loads and design. For over 10 years, he has been actively participating with the International Code Council and ASCE and has promoted the specific provisions dealing with Hawaii. This is important because at the 9 -7 -11 meeting Mr. Chock Stated that Hawaii was included in the WBDR to reflect his and others' theory and analysis that Hawaii presents too little land mass to significantly slow down the wind speeds of a hurricane. We are like a minor speed bump against the energy of a hurricane in comparison to the mainland's greater land mass. They can move right over us with little resistance. He also stated it was not meant to lump us in with the most high risk, high speed areas, that was never their intention. Mr. Chock categorized Hawaii's actual hurricane risk category as: "somewhat moderate." This theory and analysis is interesting if valid. What is perhaps more interesting is that in light of his explanation, Mr. Chock and the International Code Council would have failed to address their "Hawaii special wind speed concerns" under the appropriate area of ASCE 7 and the international codes — "Special Wind Regions." These provisions are for areas where further analysis is justified and required to accurately model and /or depict the appropriate wind loads for design due to "special" topographic features & other contributing factors. Normally this further engineering is only used to identify irregular wind speed up conditions that would be missed if utilized using the international code hurricane region wind contour maps and speeds, such as IBC 2006 fig. 1609 page 295. Statements 1 &2 1. Mr. Chock's & The International Code Council's arbitrary statewide inclusion of "Hawaii" in the IBC 2006 definition of "Windborne Debris Region" was a Gross Error. 2. Mr. Chock's and the ICC's concerns regarding their theory of insignificant wind speed slowdown due to the relatively small land mass of Hawaii versus the Continental States would have always been better addressed by the "Special Wind Region" Provisions. This is especially true after Mr. Chock completed his "effective wind speed maps" for all Islands. To anyone who has read, understands, and is nominally familiar with the relevant provisions in their totality, these statements ring clear and true. Page 3 of 5 In fact they ring so clear and true that this is exactly what the ASCE has done & codified in the latest publicized version of ASCE 7: ASCE 7 -10. The ASCE has removed Hawaii from the arbitrary and unjust inclusion in the Windborne Debris Region Definition by name. The ASCE has also newly declared Hawaii as a "Special Wind Region Statewide" (See ASCE 7 -10 ch.26 - Fig. 26.5 -1A page number: 247b. " The Practical Results of these changes are that Hawaii should now be treated equally as all other defined "Hurricane Prone Regions" under Local and International Codes. The other main result regarding "Special Wind Regions" is that Mr. Chock's modeling & endeavors, especially the use of his effective wind speed maps in the State Building Codes & Bill 270 are finally authorized & justified by the Primary Wind Load & Design Authority: ASCE 7 -10 chapter 26 (Chapter Locations changed from ASCE 7 -05) So what's the big fuss and why this Press Release/Testimony to Hawaii County Council? The Short Answer is that even though ASCE 7 is the Primary authority and has corrected these errors already, the International Codes have not. (IBC's 2006, 2009, 2012 & IRC's 2006 & 2009) These code series will take several years to cycle through both the Hawaii State Building Code and the respective County Codes. They are the base referenced codes (IBC 2006 this time around) and until these matters are corrected — A plain reading of the relevant provisions absolutely mandates (with minor exceptions ) very costly opening protection on all "buildings" newly constructed in Hawaii State. This has enormous construction cost, economic impacts and asset prioritization effects which may be wholly unwarranted given a sound interpretation of the best Science available. In fact the greatest impact may actually be realized through an inappropriate hurricane insurance risk categorization. Mr. Chock's "effective wind speed" maps identify major areas of all islands well below the normal threshold of WBDR's. There's at least a 100 square mile area surrounding greater Hilo with a 90 MPH effective wind speed, as example. This equals the design "basic wind speed" of the greater Continental U.S. outside of all "Hurricane Prone Regions ". Other Islands exhibit 85 m.p.h. effective wind speed areas equal to the lowest design "basic wind speeds" mapped in the IBC 2006, the West Coast & Western United States region. Mr. Chock's maps and basic wind speed used to model the computer simulations were based on a 1,000 year simulation of all probable tropical cyclones. There were no coefficients used improperly reducing wind speed as a function of inland distance from the coast (per Mr. Chock's non slow -down theory). So I believe his work represents the best information available presently and while Special Wind Regions usually apply to wind speed ups, Mr. Chock's maps show Hawaii's Codes should also deal appropriately with the wind reductions and lower Coastal speeds than IBC 2006's 105 m.p.h. If Hawaii State and County fail to remedy this situation now we will have the absurd situation of mandating very restrictive conditions on all new construction for a period of approximately 2 to Page 4 of 5 3 years and then rescinding those provisions when the contents of ASCE 7 -10 chapter 26 are properly incorporated into the International Codes. Builders would not be very happy and this could possibly stop or hinder necessary projects. We have an opportunity to be in step with the latest revisions and enable a smoother transition regarding future codes. Peace to all. Please allow us to sensibly and expediently remedy this situation. Thank you for your consideration of this matter. Aloha, Tim Rees Page 5 of 5