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• For each jurisdiction that did not adopt the required ordinance by January 1, 2002, which includes Indian River County, the Department of Community Affairs has adopted, by emergency rule under section 120.54(4), Florida Statutes, a map delineating the wind -speed lines of the jurisdiction. This map (see "Exhibit 2 Wind" attached) shall govern the location of wind speed lines under the Florida Building Code until 60 days after the effective date of the jurisdiction's ordinance. To comply with the referenced state requirements, Indian River County contracted with Kimley-Horn and Associates to provide the necessary interpretation and mappinc services to properly depict wind zone lines for the county. The result of this effort is the map shown in "Exhibit 3 Wind" attached. As depicted on that map, there are three wind speed lines which bisect or otherwise divide Indian River County (see "Exhibit 2 Wind"), producing wind speed zones as depicted in "Exhibit 3 Wind". As proposed, Exhibit 3 will constitute India River County's official Wind Speed Map. To disseminate information regarding the new Florida Building Code requirements for Wind -Borne Debris and to discuss the mapping provided by the county's contractor, the county Building Division staff held a public workshop on January 17, 2002. This workshop had an attendance in excess of fifty people from the building, design, and development community. ANALYSIS: Under the new code, designers/applicants have a choice between two methods t f determining the wind speed applicable to a project. They may choose to interpolate between the two contours on either side of the project location, or they may use the value shown on the county Wind Speed Map for t he zone in which the project is located. As depicted on "Exhibit 3 Wind", t he county has designated a single wind speed value between two contours. The proper value to use in establishing a single zone value is the value of the higher contour. Using the lower contour would yield wind loads below t he minimum value thereby possibly constituting a violation of the building code. While using the higher contour value yields loads slightly above t hat determined by interpolating, that value would not be in violation of t he building code. Although the county's proposed Wind Speed Map uses the wind speed contours depicted on Florida Building Code Figure 1606, a controversy has arisen regarding interpretation of that figure. Specifically, the controversy relates to Note 3 under Basic Wind Speed on Figure 1606. Generally, there are two ways to interpret Note 3. While Note 3 states that, "Islands and coastal areas outside the last contour shall use the last wind speed contour of the coastal area," there are different interpretations as to whether "last contour" means the last contour in the jurisdiction or the last contour on Figure 1606. Each interpretation has a different result as to the wind speeds applicable for Indian River County. The interpretation of staff and the county's wind speed consultant is that "last contour" means the last contour on Figure 1606, which is the 150 mile per hour contour located only in the southernmost part of the state. With this interpretation, Note 3 would not have any applicability to Indian River County's Wind Speed Zones. Consequently, the 130 mile per hour contour located along 82nd Avenue would be the western boundary of the 140 mile per hour wind speed zone. Within that zone, an applicant may use the 140 mile per hour wind speed or may interpolate based on the project location. March 5, 2002 • 91 1)I i