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

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

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’)

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

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

Wind Swath Maps Ivan Jeanne Frances Charley

GIS Database - Charlotte County All Single family units ‘new’

GIS Database – Stratifications ‘old’ units with tile roofs – Punta Gorda Isles

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)

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

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

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

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

Charley Surveyed Homes Charley 126 Surveyed Homes Sec Gust (MPH)

Frances and Jeanne Frances & Jeanne 33 Surveyed Homes Sec Gust (MPH)

Wind speed verified through portable weather stations

Ivan Surveyed Homes Sec Gust (MPH) Ivan 36 Surveyed Homes

Survey Demographics Total # samples = 195 Charley Total = 126 Ivan Total = 36 Frances / Jeanne Total = 33 Zone Zone Zone Zone Old code SBC ’94 – ‘ ’99 – ‘ New code FBC ’02 – ‘

Water Penetration: Charley (All) Old New

Water Penetration: Charley (11) Old New

Water Penetration: All storms Zone 8 (110 – 120 mph 3 sec. gust) Old New

Water Penetration: All storms Type of penetration Old New

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

Window Protection by storm and age Old New

Window Damage: 110 – 120 (8) by storm per window Old New

Window Damage: Charley data by zone per window Old New

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%)

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.

Soffits by Age Group: All data

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).

Roof Cover: Charley by zone and cover type

Roof Cover (all types): Charley by age and quantity

Roof Cover (Tile): Charley by age and quantity

Roof Cover (Shingle): Charley by age and quantity

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

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

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

Roof Cover - Shingle Results Summary  Shingle roof cover performance by age of construction:  For highest wind zone  Distinct difference in shingle performance by age  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 – % of shingled houses had no shingle damage, and the wide majority of those that had damage lost less than 5 % of their shingles.

Shingles: Regional Comparison

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%

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

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

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

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.

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