Hail Damage

After a severe hail storm, two large punctures are visible at a blister in the base flashing on an aged built-up roof. As asphalt-based roof components age, they become more fragile and susceptible to hail damage. 

Skylight after a hail storm. Acrylic skylight and smoke vent domes become more likely to suffer such damage the older they get.

More Pictures:

1. Asphalt Shingle Roof with Hail Damage

Useful Links:

1. GeneralThe Hail Facts + Statistics page at the Insurance Information Institute's website is a good source of information. 

2. General: "Impact Resistant Roof Coverings" provides information about the test standards which determine impact resistance ratings for roofing materials. Available at the Blueprint for Safety website.

3. General: "Reduce Hail Damage to Homes" is a brief article about how the risk of hail damage depends on the geographical location of your home and the type of roofing material you have. Produced by the Insurance Institute for Business & Home Safety.

4. Inspection of hail-damaged roofs: Mastering Roof Inspections: Hail Damage, Part 1 at the International Association of Certified Home Inspectors' website is worth taking a look at. This hail damage inspection guide has eleven more parts, which can be accessed from this page. The focus is on steep-slope residential roofing.

5. Insurance: An interesting article about the rise in hail damage claims from the point of view of the insurance industry on the Claims Journal site.

6. Shingles - Asphalt: "Effects of Hail on Asphalt Roofing Shingles" provides basic standard information. This short technical bulletin is available on the Canadian Asphalt Shingle Manufacturers' Association website.

7. Shingles - Asphalt: "Asphalt Shingles: Relative Impact Resistance" presents the results of testing performed by the Insurance Institute for Business & Home Safety which compares how different types of asphalt shingles should be expected to perform in a hail storm.

8. Shingles - Asphalt: "Guidelines to Assess Hail Damage to Shingle Roofs" is a short and very useful paper available at the website of Nelson Forensics. The paper is from 2012.

9. Slate Roofs: "Natural Slate Hail Testing: Impact Resistance of Natural Slate Confirmed" is available at the website of the National Slate Association

10. Spray Polyurethane Foam: "Hail Resistance Test of Sprayed Polyurethane Foam (SPF) Roof Systems" examines the performance of various SPF roof systems during hailstorms. Well-researched. Available in the Technical Library at the NRCA website.

11. Technical: "Effects of Hail on Residential Roofing Products" examines the effects of hail on asphalt, wood, and concrete tile shingles. Includes useful information about the physical aspects of hail itself. From 1991. Available in the Technical Library at the NRCA website.