IBHS Roofing Research
ARMA Steep Slope Committee MeetingAugust 14, 2013 Tanya M. Brown, PhD
South Carolina Wind and Hail Underwriting Association Research Engineer
Large Test Chamber
145 ft W x 145 ft L x 70 ft H test chamber
60 ft W x 30 ft H wind inlet
105 fans, each with 350 hp motors
Enough power for 9,000 homes
Flow volume = 20 X GREATER THANNiagara Falls
High-definition cameras & TV lighting
Recreating Mother Nature in the Lab
Wind Data Gathered in
Field During Disasters Engineers Use Data to Recreate
Actual Wind Scenarios in Lab
105 Fans Bring Scenarios to Life
IBHS Research Center Results
Gain a better understanding of:
• The risks themselves through field work and environmental
analysis
• The real-world impact through damage surveys and claims
analysis
• The existing test methods and their true applicability to actual
performance
• Cosmetic vs. functional damage through full-scale testing • Repair methodologies through full-scale testing after aging • Effects of long-term aging on various materials
IBHS Research Center Hail Projects
Field Work: Hail Events & Characteristics
Making Realistic Hailstones
Lab Work: Hail Damage to Roof & Building
Components Small-Lab Testing &
Full-Scale Testing Analysis: Correlate
Radar & Ground Hail Observations
Collaborative Result: Improved Estimates
of Hail Events
Analysis: Correlate Damage with Hail Event Characteristics
Closed Claim
Studies Aging Studies
Goal: Improved Prediction of Hail
Risk & Losses
Goal: Improved Performance of Building Products Collaborative Result: Improved Product Performance Standards Collaborative Result: New / Improved Hail Impact Test Methods
Hailstone Characteristics Field Project
•
Collect scientific
information on the
properties of severe
hailstones:
1. Size
2. Mass
Hailstone Characteristics Field Project
•
Develop relationships
between hailstone
characteristics and
environmental/radar
data
•
Coordinated field
deployment
•
Project domain:
Northern, Central and
Southern Plains
Hailstone Characteristics Field Project
May 25-June 8, 2012 May 16-22, 2013 May 30-June 5, 2013
15 datasets 33 datasets 6 datasets
9 storms 8 storms 4 storms
7 days 4 days 3 days
0.16 in. - 3.05 in. sizes 0.04 in. – 1.89 in. sizes 0.28 in.– 4.21 in. sizes 9 psi - 620 psi
compressive stress
1 psi – 673 psi
compressive stress
8 psi – 1097 psi compressive stress
Making Realistic Hailstones
Density
• Artificial hailstones—varies from
0.45-1.1 g/cm3
• Natural hailstones—varies from
0.1-0.9 g/cm3 (historical studies)
Compressive Stress
• Artificial hailstones—varies from
3-308 psi
• Natural hailstones — 1-1097 psi
Full-Scale Impact Testing
• 12 hail “pods” on upper
catwalk
- Computer-controlled firing system
- Fully-controllable shooting speeds - Fully-controllable
Full-Scale Impact Testing
• 3 sizes:
- 1 in. - 1.5 in. - 2 in.
• Adaptable for different
sizes
• Structural vs. Aesthetic
Damage
• Repair vs. Replace
Full-Scale Impact Testing
• Comparison of performance of
shingle types
- Impact-rated (Class 4)
architectural asphalt shingles - Non-rated 3-tab asphalt shingles - Metal panel: two installation
types
• Soft metal materials • Windows and door
Full-Scale Impact Testing
Test New & Aged Specimens
Repair & Replace Methodologies
Test against water intrusion Test against
water intrusion Age
Provide Guidance on Best Practices
Future
Research
(after
automatic
hailstone
production)
Small-Lab Impact Testing
Systematic approach to
study:
1. Aging and climate effects
2. Materials—start with 3-tab and laminate asphalt shingles
3. IR vs. non-IR products
4. Structural vs. aesthetic damage 5. UL, FM, IBHS hailstone impacts 6. Material warranties
7. Roof pitch
Goal = Develop statistically based damage curves for size, density, and hardness of
Aging Studies
•
Naturally age small roof specimens for
wind and hail testing for up to 20 years
•
Test at five-year increments
(baseline = new)
•
Multiple test panels for each age, north
and south facing
Aging Studies
• 50 in. x 66 in. panels
- 2 north-facing - 2 south-facing
• 36 in. x 36 in. panels
- 1 north-facing - 1 south-facing
Aging Studies
• For all specimen panels, 5-minute sampling frequency of:
- Temperature of shingle surface at center of panel
- Temperature between shingles and underlayment at center of panel
- Temperature between underlayment and deck at center of panel
• Six specimens with additional measurements:
- Temperature and relative humidity inside attic
- Shingle surface temperature measurements at rakes, eaves, and edges
May 24, 2011 DFW Claims Study
• Hailstorms caused more than $875 million in insured losses • Claims study comparing:
- Roofing material performance - Aging
- Relative difference in roofing damage vs. walls/windows/doors/trim damage
- Radar-estimated hail severity vs. claim severity
• More than 67,000 policies in force • More than 6,600 claims
May 24, 2011 DFW Claims Study
Roof Damage 91.7% Other Damage 6.1% Wall Damage 0.9% Door Damage 0.1% Window Damage 1.3% Other 2.2%May 24, 2011 DFW Claims Study
3-tab comp / Arch Comp 79.19% Unknown 18.80% Metal 0.65% Tile 0.93% Wood 0.24% Slate 0.20% Other 2.02%
May 24, 2011 DFW Claims Study
May 24, 2011 DFW Claims Study
Roofing Best-Practices Manuals
• Partnership between RICOWI, IBHS, roofing industries (tile,
wood, metal, asphalt, single-ply)
• Electronic guides with pictures, descriptions, links to
materials, videos
• Intended audiences
- Roofing consultants - Roofing contractors
- Insurance agents and underwriters - Insurance claims adjusters
- Building code officials - Inspectors
Roofing Best-Practices Manuals
• Content
- General Product Information
- Standards and Codes—Wind, Fire, Hail, Seismic, Cold Climates
- Energy Efficiency
- Installation Guidelines
- Repair and Maintenance Guidelines
- Damage Issues—Wind, Fire, Hail, Seismic, Cold Climates - Industry Resources
