Download presentation
Presentation is loading. Please wait.
Published byOmar Rover Modified over 9 years ago
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
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
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 Ivan Jeanne Frances Charley
7
GIS Database - Charlotte County All Single family units 2002 - 2004 ‘new’
8
GIS Database – Stratifications ‘old’ units with tile roofs – Punta Gorda Isles
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 photographs –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 Charley 126 Surveyed Homes 2002-2004 1994-2001 3-Sec Gust (MPH)
15
Frances and Jeanne Frances & Jeanne 33 Surveyed Homes 2002-2004 1994-2001 3-Sec Gust (MPH)
16
Wind speed verified through portable weather stations
17
Ivan Surveyed Homes 2002-2004 1994-2001 3-Sec Gust (MPH) Ivan 36 Surveyed Homes
18
Survey Demographics Total # samples = 195 Charley Total = 126 Ivan Total = 36 Frances / Jeanne Total = 33 Zone 8 110 - 120 Zone 10 130 - 140 Zone 11 140 - 150 Zone 8 110-120 Old code SBC ’94 – ‘9812210 5 ’99 – ‘011023141012 New code FBC ’02 – ‘0411122316
19
Water Penetration: Charley (All) Old New
20
Water Penetration: Charley (11) Old New
21
Water Penetration: All storms Zone 8 (110 – 120 mph 3 sec. gust) Old New
22
Water Penetration: All storms Type of penetration Old New
23
Water Penetration Results 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 Protection by storm and age Old New
25
Window Damage: 110 – 120 (8) by storm per window Old New
26
Window Damage: Charley data by zone per window Old New
27
Window Protection: 2004 and Future Use Old New Window protection use in 2004 and future storms % of homes in that region that used left column protection in 2004 (% that intend to use protection in future seasons) CharleyIvanFrances / Jeanne No protection60 % (11%) 58% (33%) 16% (16%) Plywood7% (13%) 36% (36%) 13% (6%) Shutters27% (74%) 6% (27%) (53%) (72%) Impact Glass7% (3%) 0% (3%) 19% (6%)
28
Window Protection Results 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 Damage Results 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: Charley by zone and cover type
32
Roof Cover (all types): Charley by age and quantity
33
Roof Cover (Tile): Charley by age and quantity
34
Roof Cover (Shingle): Charley by age and quantity
35
Roof Cover (Tile): Charley (11) by age and quantity
36
Roof Cover - Tile Results 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 - Shingle Results 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
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.