Corrosion of Residential Fasteners

Presented to the

Florida Building Commission

State of Florida Department of Business and Professional Regulation

by

Kurtis R. Gurley, Ph.D., kgurl@ce.ufl.edu, (352) 392-9537 x 1508

1. Issues

• Anecdotal information indicates that corrosion of fasteners has been observed across a range of installations
• The problem is more serious in coastal environments due to presence of chloride ions
• Increased manufacturing of these products outside the United State may be contributing to the problem
• The 2015-2016 corrosion study focused on
• Electrogalvanized roofing fasteners conforming to ASTM A641 or TAS 114 Appendix E standards
• Hot dipped fasteners
• Roof tile fasteners
• Screen enclosure fasteners
• The 2016-2016 corrosion study identified performance issues that warrant further testing

2. Relevant Sections of the Code (and Related Documents)

• 1622.1.2, Florida Building Code—Building
• 1506.4 – 1506.7, Florida Building Code—Building
• 1517.5.1 – 1517.5.2, Florida Building Code—Building
• Guide to Aluminum Construction in High Wind Areas
• TAS 114 Appendix E
• ASTM A90
• ASTM A641
• ASTM A153
• ASTM B117-11
• ASTM G85-11

3. Statement of Work

The proposed testing is briefly described as follows:

· Hot dipped roofing fasteners performed much better than electrogalvanized fasteners in the 2015-2016 study. Fasteners conforming to the ASTM A153 hot dipped standard and the ASTM A641 minimum coating standard will be tested for relative performance.

· The 2015-2016 study revealed that the ceramic coating on stainless steel masonry screws (commonly used for screen enclosures) peeled during the corrosion testing. This may create issues with unlike metal reactions when these fasteners are used in aluminum enclosures. The proposed testing will install ceramic coated SS screws in aluminum prior to corrosion testing in order to investigate the implications of loss of coating with respect to corrosion at the unlike metal interface.

· Additional tile fastener testing will be conducted to add multiple commonly used products to the limited results from the 2015-2016 study.

· HVAC and metal panel clips and fasteners will be included in the 2016-2017 test matrix

The test protocol includes the following:

• Apply TAS 114 Appendix E testing (Section 2.6.1) to evaluate the degree of corrosion resistance
• All available descriptive information regarding tested specimens will be included in the reporting
• Testing will be conducted on both new and installed fasteners to determine the influence of installation on corrosion resistance
• Testing will include multiple samples of each specimen configuration
• Interpret results and produce a report that explains the results and implications for the Code

4. Deliverables

· An interim report detailing the current status and progress toward completing the scope of work will be submitted by February 15, 2017. The interim report will be presented to the Commission’s Roofing Technical Advisory Committee at a time agreed to by the Contractor and the Department’s Project manager.

· A final report providing technical information on the problem background, results and implications to the Code submitted to the Program Manager by June 1, 2017. The final report will be presented to the Commission’s Roofing Technical Advisory Committee at a time agreed to by the Contractor and the Department’s Project manager.

· A breakdown of the number of hours or partial hours, in increments of fifteen (15) minutes, of work performed and a brief description of the work performed.  The Contractor agrees to provide any additional documentation requested by the Department to satisfy audit requirements.

5. Budget

Table 1. Budget

Budget	Amount
Salaries	$26,419
Fringe Benefits	$6,614
Equipment	$0
Utilities	$0
Travel	$0
Misc. (Materials/Supplies)	$2,500
Indirect Cost/Overhead	$3,553
TOTAL	$39,086

Research personnel time and will be reported and certified using a “loaded” rate computed from the following table. Note that the indirect cost shown in Table 1 is computed from the indirect cost in Table 2 + the indirect cost associated with the travel and miscellaneous categories.

Table 2. Breakdown of the hourly compensation rate

Person	Hours	Hourly Rate	Fringe	Tuition	IDC	Total
K. Gurley	160	$76.35	$20.54	$0.00	$9.69	$17,053
Lab Staff*	120	$52.44	$19.35	$0.00	$7.18	$9,476
Admin Asst	80	$23.88	$10.70	$0.00	$3.46	$3,043
Undergrad. Students	500	$12.00	$0.30	$0.00	$1.23	$6,765
*Multiple lab staff may be used. Maximum anticipated hourly rate shown (Jon Sinnreich)