MINUTES

FLORIDA BUILDING COMMISSION

WIND MITIGATION WORKGROUP

May 5, 6 and 7, 2008

Melbourne , Florida

Crowne Plaza Melbourne Oceanfront Hotel

2605 North AIA Highway

1-800-980-6429

Wind Mitigation Workgroup Members Present

Representation                                                                                    Member

Commission/Roofing                                                                             Chris Schulte

Commission/Contractor                                                                        Matt Carlton

FRSA/Roofing                                                                          Burt Logan

Insurance                                                                                              Tim Reinhold

FHBA                                                                                                  Richard Reynolds

Building Officials                                                                                   Bill Dumbaugh
Building
Officials                                                                                   Jim Schock

 

1.  Discussed Wind Mitigation Retrofits Provisions for 2007 Florida Building Code

            a. Reviewed and Discussed Gable End Bracing Provisions:

Richard Reynolds provided a status of the revisions to Appendix A and stated that the drafts of Appendix A material will be available for review Monday, May 11, drawings by Friday, the 16th of May. 

 

2.  Reviewed and Discussed Other Wind Mitigation Retrofit Provisions:  The Workgroup reviewed the working draft and provided the following comments and revisions:

 

611.7 101.1  When a roof covering on an existing site-built - single family residential structure is removed and replaced, the following procedures shall be permitted to be performed by the roofing contractor:

(a) Roof-decking attachment andfor fastenersing shall be strengthened and corrected as required by Section 611.7.1 201.1.

 

611.7.1 201.1  Roof decking sheathing fastening attachment and fastening for site-built single family residential structures. 

     

611.7.2 Roof secondary water barrier for site-builtingle family residential structures.  A secondary water barrier shall be installed using one of the following methods when roof covering is removed and replaced:

1. In either HVHZ or non-HVHZ regions,

a) All joints in structural panel roof sheathing or decking shall be covered with a minimum 4 in. wide strip of self-adhering polymer modified bitumen tape applied directly to the sheathing or decking.  The deck and self adhering polymer modified bitumen tape shall be covered with one of the underlayment systems approved for the particular roof covering to be applied to the roof. 

 

bc) In the HVHZ, the entire roof deck shall be covered with an approved asphalt impregnated 30# felt underlayment or approved synthetic underlayment installed with nails and tin-tabs as required for the HVHZ in accordance with Sections 1518.4 of the Florida Building Code, Building or R4402.7.2, R4402.7.3, or R4402.7.4 of the Florida  Building Code, Residential.  This method shall also be acceptable in the non-HVHZ regions of Florida.  (No additional underlayment shall be required over the top of this sheet).  The synthetic underlayment shall be fastened in accordance with the manufacturer’s recommendations.

 

e) Application of a two-part urethane based closed cell spray-on adhesive to the attic side of the joints between the sheathing and along both sides of the truss top chords or rafters shall be deemed to meet the requirements for the secondary water barrier. 

2. Outside the High Velocity Hurricane Zone:

 

a.  The entire roof deck shall be covered with an approved self-adhering polymer modified bitumen cap sheet meeting ASTM D 1970 or an approved self-adhereing synthetic underlayment installed in accordance with the manufacturer’s installation instructions.  No additional underlayment shall be required on top of this cap sheet for new installations.

 

b.  d) In regions of Florida oOutside of the HVHZ, Aan underlayment system approved for the particular roof covering shall be applied with the following modification:

(1) For roof slopes that require one layer of underlayment, complying with section 1507.2.3 of the Florida Building Code, Building fastened as described below orA a layer of approved asphalt impregnated approved ASTM D 226 Type I or Type II (#30) felt underlayment or approved synthetic underlayment shall be installed. The felt or synthetic underlayment is to be fastened with 1” round plastic cap or metal cap nails, attached to a nailable deck in a grid pattern of 12 inches (305 mm) staggered between the overlaps, with 6-inch (152 mm) spacing at the overlaps.  The synthetic underlayment shall be fastened in accordance with the manufacturer’s recommendations.

 

(2) For roof slopes that require two layers of underlayment, an approved asphalt impregnated ASTM D 226 Type I or Type II (#30) underlayment of 2:12 to 4:12 an additional layer of felt shall be installed in a shingle-fashion and lapped 19” and fastened as described above. An approved synthetic underlayment shall be installed in accordance with the manufacturer’s installation instruction. (No additional underlayment shall be required over the top of this sheet).

 

 

 

201.3 611.8.1 Roof-to-wall connections for site-built single family residential structures.  Where required by Section 611.8 101.2, the intersection of roof framing with the wall below shall be strengthened by adding metal connectors, clips, straps, and fasteners such that the performance level equals or exceeds the uplift capacities as provide sufficient resistance to meet the uplift loads specified in Table 611.8.1 201.3 either because of existing conditions or through retrofit measures. As an alternative to an engineered design, the prescriptive retrofit solutions provided in Sections 611.8.1.1 201.3.12 through 611.8.1.6 201.3.45 shall be accepted as meeting the mandated roof-to-wall retrofit requirements. 

 

Exceptions:

1.  Where it can be demonstrated (by code adoption date documentation and permit issuance date) that roof-to-wall connections and/or roof-to-foundation continuous load path requirements were required at the time of original construction.

2.   Roof- to- wall connections shall not be required unless evaluation and installation of connections at gable ends or all corners can be completed for 15% of the cost of roof replacement.  For house that have both hip

 

                  The workgroup reviewed the Roof Gravel Criteria Proposal for 2007 Florida Building Code and made the following recommendation:

 

BALLAST. Ballast is any item having weight that is used to hold or steady an object. In roofing, ballast comes in the form of large stones or paver systems or light-weight interlocking paver systems and is used to provide uplift resistance for roofing systems that are not adhered or mechanically attached to the roof deck.

 

1.      ADJOURNED: 10:30 am