Post 2004 Hurricane Field Survey Evaluation of the Relative Performance of the Standard Building Code and the Florida

1. Post 2004 Hurricane Field Survey  Evaluation of the Relative Performance of the Standard Building Code and the Florida Building Code Kurt Gurley � UF Jeff Burton � IBHS Makola Abdullah � FAMU Forrest Masters � FIU Tim Reinhold � IBHS My name is Forrest Masters, and I belong to a community of wind engineers seeking to reduce loss of property and life from extreme wind events. Presently, I am a PhD candidate in the structures group of the Civil and Coastal Engineering Department at the University of Florida. Today I am excited to present a topic that I am very passionate about: the measurement, modeling and simulation of hurricane wind forces. The subject of hurricanes is so vast. As a civil engineer, I am interested in how winds impinge upon low-rise structures. >> NEXT SLIDE My name is Forrest Masters, and I belong to a community of wind engineers seeking to reduce loss of property and life from extreme wind events. Presently, I am a PhD candidate in the structures group of the Civil and Coastal Engineering Department at the University of Florida. Today I am excited to present a topic that I am very passionate about: the measurement, modeling and simulation of hurricane wind forces. The subject of hurricanes is so vast. As a civil engineer, I am interested in how winds impinge upon low-rise structures. >> NEXT SLIDE

2. Project Goal Determine if 2002 code change reduced the vulnerability of residential single family homes Quantitative rather then anecdotal Physical damage $ Loss ratio Behaviors (mitigation & evacuation) Stratify results by wind speed and code with better response characteristicswith better response characteristics

3. Additional Objectives Include and contrast structures in each of the areas impacted by 2004 storms Subject targets � site built single family Post Andrew, pre-Florida Building Code 1994 � 2001 (�old�) Post Florida Building Code 2002 � 2004 (�new�)

4. Methodology Pre-arranged appointments with randomly selected homeowners to gather damage information Interview homeowner Inspect property Prior knowledge of home details ( Yr of construction, Roof / Wall type, etc.) home location relative to peak 3-second wind speeds NO prior knowledge of damage no visual bias to sample selection to determine �average� damage and $ loss

5. Tools Access to wind swath maps Vickery: Applied Research Associates Powell: NOAA Access to county databases: Home location Homeowner Year of construction Roof cover (asphalt, tile) Roof type (hipped, gable) Wall type (masonry, wood frame) Appraised value pre-2004 storm season

6. Wind Swath Maps Charley

7. GIS Database - Charlotte County All Single family units 2002 - 2004 �new�

8. GIS Database � Stratifications

9. Stratified Sampling Procedure Overlay wind swath maps with homes that fit desired characteristics (age, roof cover, etc.) Randomly select homes across desired wind swath contours The homeowners contacted by phone in random order (25% success rate)

10. Survey Details: Inspection Digital photograph s All angles and corners of subject Surrounding terrain Distance to adjacent large objects in all directions Sketch elevations and plan view

11. Survey Details: Inspection Attic inspection Sheathing type and thickness Sheathing nail size, edge and field spacing Gable end bracing Roof to wall strap installation Garage inspection Pressure rating, bracing Location, size and type of every window and door includes protection details & damage

12. Survey Details: Interview Evacuation behavior Mitigation behavior (shutters) Indicate damage on elevation sketches Water penetration Roof cover failure Soffit failure Window and / or shutter failure Scan any damage pictures Insurance reimbursement information

13. Survey Details: Interview Data entered directly into handheld PDA Upload to access database

14. Charley Surveyed Homes

15. Frances and Jeanne

16. Wind speed verified through portable weather stations

17. Ivan Surveyed Homes

18. Survey Demographics

19. Water Penetration: Charley (All)

20. Water Penetration: Charley (11)

21. Water Penetration: All stormsZone 8 (110 � 120 mph 3 sec. gust)

22. Water Penetration: All stormsType of penetration

23. Water PenetrationResults Summary Water penetration by code: It is not clear from the study that the FBC provides improvement in preventing water penetration. 1994 � 1998 more likely to have ceiling damage

24. Window Protectionby storm and age

25. Window Damage: 110 � 120 (8)by storm per window

26. Window Damage: Charley data by zone per window

27. Window Protection: 2004 and Future Use

28. Window ProtectionResults Summary Mitigation effectiveness � shutter use: A significant percentage (3 - 4%) of unprotected windows were damaged in the highest wind zone (140 � 150 mph) in Charley, while protected windows experienced significantly less damage. At the lower wind zone 8 (110 � 120 mph gust), protected windows permitted almost no damage, while the percentage of damaged unprotected windows was small but consistent among storms.

29. Soffits by Age Group: All data

30. Soffit DamageResults Summary Soffit performance with age of construction: Increased likelihood of soffit damage with increasing age of structure (over the surveyed range 1994 � 2004).

31. Roof Cover: Charleyby zone and cover type

32. Roof Cover (all types): Charleyby age and quantity

33. Roof Cover (Tile): Charleyby age and quantity

34. Roof Cover (Shingle): Charleyby age and quantity

35. Roof Cover (Tile): Charley (11)by age and quantity

36. Roof Cover - TileResults Summary Tile roof cover performance: Few surveyed tile roof homes of any age group had no cover damage Higher probability of field tile loss in �94 � �01 homes compared to new construction 2002 � 2004 15% had tile damage exceeding 5%, (mostly ridge cap loss) 1999 � 2001 60% had over 5% damage 44% over 10% damage 22% over 25% damage 1994 � 1998 60% had 6-25% damage

37. Roof Cover (Shingle): Charley (10)by age and quantity

38. Roof Cover - Shingle Results Summary Shingle roof cover performance by age of construction: For highest wind zone 140 - 150 Distinct difference in shingle performance by age 1994 - 1998 significant quantities of shingle damage 1999 � 2001 less damage 2002 � 2004 small quantity of damage on average 1994 � 1998 Every shingle house surveyed in zone 11 had shingle damage, all had at least 10% shingle loss, and most had between 25 and 50% loss. 2002 � 2004 30% of shingled houses had no shingle damage, and the wide majority of those that had damage lost less than 5 % of their shingles.

39. Shingles: Regional Comparison

40. Roof Cover - ShingleResults Summary Shingle roof cover performance by wind speed: Charlotte County 110 � 120 mph : 32% of homes had shingle damage 130 � 140 mph : 65% 140 � 150 mph : 79%

41. Roof Cover (Shingle): Charley (8)by age and quantity

42. Roof Cover (Shingle): Ivan (8)by age and quantity

43. Roof Cover (Shingle): Frances (8)by age and quantity

44. Roof Cover - Shingle Results Summary Shingle roof cover performance by region: 110 � 120 mph 3 sec. gust Charlotte County (32% of homes damaged) St. Lucie County (80%) Escambia County (50%) Charlotte County suffered less quantity of damage on average than those in the Ivan and Frances / Jeanne regions.

45. Concluding Remarks Major findings Demonstrate: Effectiveness of window protection Improvement in shingle performance Tile: older more likely to experience field tile damage Some aging effects on roof cover performance Support efforts to improve: Water Intrusion standards Tile roof cover installation standards Ridge cap installation standards Soffit installation standards