Is Your Home Protected From Hail Damage?A Homeowner’s Guide to Hail Retrofit

A Homeowner’s Guide to Roofing and Hail

Prepared by the Institute for Business & Home Safety (IBHS). The Institute for Business & Home Safetyis a nonprofit research and communications organization sponsored by the insurance industry and dedicated to reducing deaths, injuries, property damage, economic losses and human suffering causedby natural disasters.

disclaimer

The purpose of this document is to provide homeowners with guidance on ways to retrofit one- and two-family homes in order to reduce losses from hail damage. It contains suggestions and recommendationsbased on professional judgment, experience and research and is intended to serve only as a guide. Theauthors, contributors and publisher disclaim all warranties and guarantees with respect to the information in the document and assume no liability or responsibility with respect to the information.

© 2002 Institute for Business & Home SafetyAll rights reserved.

ISBN 1-885312-19-9

table of contents

introduction .........................................................1

selecting an impact-resistant roof covering ...2

types of roof coverings .....................................4

selecting a contractor........................................7

commonly asked questions ..............................8

terms you should know ....................................10

additional sources of information ...................12

table of contents

A Homeowner’s Guide to Roofing and Hail

introduction

uilding? Buying? Need to dosome repairs? This is the perfect time to give serious

thought to the hazards your homeis exposed to. One of the most vul-nerable spots on your home is theroof. And one hazard most home-owners can expect to face at somepoint is hail.

Compared to earthquakes and hurricanes, hail might seem like aminor concern. True, hailstormsdon’t cause the loss of life, but they can shatter windows, leavepockmarks in siding and, mostimportant, destroy or damage roofcoverings. Here are some tips tohelp you protect your investment.

introduction

B

1

Slate roof

damaged

by hail.

Haag Engineering Co., copyright 1992.

2

How do you know if a roof covering is impact-resistant? Oneway is to look for UnderwritersLaboratories’ measuring stick: theUL 2218 standard. The UL testinvolves dropping steel balls ofvarying sizes from heights designedto simulate the force of free-fallinghailstones. Four impact-level desig-nations will help you compareproducts: roof coverings that showthe most resistance earn a Class 4rating; the least, a Class 1 rating.

You put a lot of time, work andmoney into your home. Naturally,you want to use the best productsavailable. In terms of roof coverings,this means a UL 2218 rating ofClass 4. A Class 4 rating tells youthat a sample of the product did notcrack when hit twice in the samespot by a 2-inch steel ball, which, ina storm, would translate into quite ahailstone. A Class 1 rating signifiesresistance to a 1 1/4-inch steel ball;Class 2, a 1 1/2-inch steel ball; andClass 3 a 1 3/4-inch ball.

The UL 2218 standard is the bestmethod to test impact resistance,but it isn’t perfect and works betterfor some coverings than for others.UL 2218 measures whether a product cracks under impact. Someroof coverings, in particular some made of metal, may resist

cracking but can be dented anddimple. So while they test well, theymay perform poorly in practice.Keep this in mind when using theUL standard as a gauge of quality.

And to cover all the bases, alsocheck for wind-resistance featuresand a fire-resistance rating. Consulta design professional, your insur-ance company or roofing installerabout steps you can take— fastening vulnerable rows ofasphalt shingles with adhesive, for example, or tying down tile with a screw and wire instead of nails— to help your roof coveringstand up better against high wind.

Fire ratings range from Class Amaterials that are effective againstsevere fire exposure to Class Cmaterials that are only effectiveagainst light exposure. Productsthat are untested or have failed atest are listed as “nonrated.”

A Homeowner’s Guide to Roofing and Hail

Tile roof

damaged

by hail.

selecting an impact-resistant roof covering

Haag Engineering Co., copyright 1992.

3selecting an impact-resistant roof covering

asphalt

metal

cedar

slate

clay tile William Spaulding

Although asphalt shingles are the most common,roof coverings come in a variety of colors andstyles. Which is best for your home?

4

There are many different types ofresidential roof coverings to choose from.

What type best suits your taste and the level of hail risk where you live?

Asphalt shingles are found on mosthomes in the United States and canbe reinforced with either organic orfiberglass materials. Fiberglassshingles last up to 20 years andhave a Class A fire rating.

Modified asphalt shingles includeSBS (a rubber-type compound) orAPP (a plasticizer) and are likely to perform well in hailstorms.Without them, fiberglass composi-tion shingles stand up moderatelywell to hail.

Metal, primarily thought of as acommercial roofing material, hasbecome an attractive alternative forsome homeowners. Not only dothey last up to 40 years, metalroofs are also relatively lightweightand may have a Class A or B firerating. But beware of their perfor-mance in hailstorms. Unlike othershingles that can ease back intoshape, metal can dimple permanently.

Slate tends to be long-lasting (up to 100 years) but also moreexpensive than other materials.And you would need someone with

A Homeowner’s Guide to Roofing and Hail

types of roof coverings

asphalt shingles

metal shingles

5

skill and experience to apply it,which can add to the cost. Anotherpoint to consider: slate is veryheavy. Some roof structures areunable to support this type of roofcovering. Be sure to check with aregistered design professionalbefore spending all of that money.

Synthetic roof coverings (e.g., fibercement or molded plastic) simulatevarious types of traditional roofcoverings, such as slate and woodshingles and shakes. Their perfor-mance varies by product.

Tile is popular in some areas, butits performance in hailstorms variesby type. Concrete tiles are moredurable and can last more than 20years, while clay tiles are brittleand can be easily chipped or broken. And another thing: likeslate, tile is heavy. If you arereplacing another type of roof withtile, you will need to verify that thestructure can support the weight.Also, heavy products can takelonger to install, so labor costs maybe significantly more.

Wood shingles and shakes aremade from cedar, southern pine orother woods. Though some liketheir appearance, wood shinglesand shakes perform only moderatelywell against hail. Two other thingsto consider: 1) some local codeslimit their use; and 2) unless they’retreated with a fire retardant, theymay not have a fire rating.

types of roof coverings

slate shingles

synthetic roof

coverings

6

Before making your roofing selection, take your time and checkout the variety of products. Lookat full-size samples of the roof covering you’re considering. Youcan also get information by look-ing at manufacturers’ brochures orvisiting a house that is roofed witha particular product. Most roofingmaterials will come with some typeof warranty, but they have limitedvalue. Even the most comprehen-sive warranties will not cover alldamages under every circumstance.Be sure to read the fine print.

Roofing products have changedsignificantly over time. The varietyof choices in materials, appear-ances and prices allows you to getthe look you want without com-promising quality. Above all, lookfor materials that will protect yourhome for many years.

Information compiled in cooperation with theNational Roofing Contractors Association.

Photos of roof coverings courtesy of MichaelGrimm, This Old House magazine.

A Homeowner’s Guide to Roofing and Hail

cedar shingle

tile shingle

7

Of course you’ll want to carefullyevaluate any contractor you consider so you can be confidentthe job will be done right. Your insurance company may be able to give you names of qualified roofing contractors inyour area. Or, you can contact theNational Roofing ContractorsAssociation at 1-800-USA-ROOFfor assistance or check its website(www.nrca.net).

Here are some things to consider:

• Look for an established, licensedor bonded roofing contractor.Ask for references and call themup.

• Ask to see certificates of insurance. Make sure that both liability and workers com-pensation insurance coveragesare carried and are in force while roofing work is beingdone.

• Insist on a detailed, written estimate that clearly states thequantity of materials needed;labor charges; work specifica-tions, including approximatestarting and completion datesand payment procedures.

• Carefully review and understandany warranty and watch for conditions that would void it.

• Be skeptical about lowest bids orthose considerably lower thanothers written for the same job. Many contractors seemattractive because of low bids;however, they may be uninsuredand may perform substandardwork. If it looks too good to betrue, it probably is.

• Contact your local Better BusinessBureau to check for complaintsfiled against the contractor.

Adapted from material supplied by theNational Roofing Contractors Association.

selecting a contractor

selecting a contractor

Asphalt roof

shingles

damaged

by hail.

8A Homeowner’s Guide to Roofing and Hail

Won’t the expertspick the best roofcovering for me?

No. Building codes do not requirethat roofs be impact resistant, sodon’t rely on codes or regulations toprotect you. And if you are having ahome built, don’t assume that thearchitect or designer will do yourplanning for you. For the most part,they call for a generic type, such aswood shakes, asphalt compositionshingles, or clay or concrete tiles. Ifyou are putting on a new roof covering or replacing an existingone, it’s up to you to make sureyour new roof covering will resistimpacts, especially if you live in ahail-prone area.

I have insurance.Why should I worryabout hail damage?

Sure, standard homeowners policies will cover hail damage. Butthat doesn’t mean you’re free and clear and can just leave the problem to your insurancecompany. All policies have somekind of deductible or co-payment.No matter what your type of coverage, as a homeowner, you will be reaching into your ownpocket to repair or replace a roof

damaged by hail. Repairing orreplacing a roof covering is a majorinconvenience. Knowing whichroof coverings resist impact well,and which do not, can save you alot of trouble and a lot of money.

What causes a roofto wear out?

Several factors can speed a roof’sdecay, including ultraviolet lightfrom the sun and temperatureextremes in your area. Exposure towind, snow, ice and rain and foottraffic on the roof don’t help either.Darker color shingles, because theyabsorb more light, may have shorterservice lives than lighter colors insouthern climates.

Why do wood roof shingles split and crack?

Wood naturally splits and cracks as part of the aging process. This is largely due to swelling andshrinking caused by moisture andsubsequent drying.

commonly askedquestions

Photo: Gene E. Moore

9

Can an existingasphalt shingle roof be covered with another?

A roofing contractor may be ableto apply the new material directlyon top of the old layer, dependingon its condition. Although thissaves a little bit of time and money,experts strongly recommendagainst it, especially in hail- orwind-prone regions. Hail tends tocause more damage when there ismore than one layer of shingles. Inwindy areas, the new layer will not grab as tightly as it should if there is a pre-existing layer under it. Any other type of roofcovering is typically removedbefore the new roof covering is installed.

Can compositionshingle roofs berepaired?

Yes. If damage is minor, a roofingcontractor can remove individualshingles and replace them.

Can’t I just do thework myself?

Only if you have sufficient experi-ence in replacing roof coverings.Otherwise, don’t try it. Most roofing jobs are not for the do-it-yourselfer. Novices can do moreharm than good if they useimproper roofing techniques. Moreimportantly, they can severelyinjure themselves by falling off oreven through a roof. Professionalroofing contractors are trained todo the job safely and efficiently.

What sort of ongoingmaintenance should I do?

Inspect the roof in the fall and spring for cracked or curlingshingles, and clean rain guttersfilled with dead leaves and otherdebris. It's best to use binocularsand do this from the ground. If youreally feel that you need a closerlook, use a firmly braced or tied-off ladder equipped with rubbersafety feet. Wear rubber-soled shoesand stay on the ladder (and off theroof) if possible so you don’t damage your roof or yourself.

commonly asked questions

10

Deck/Sheathing:The surface — usually plywood ororiented-strand board (OSB) — towhich roof underlayments and cov-erings are applied.

Dormer: A small structure projecting from asloped roof, usually with a window.

Drip edge:An L-shaped strip (usually metal)installed along the edges of theroof to allow water to drip clear ofthe deck, eaves and siding.

Eave:The horizontal loweredge of a sloped roofwhere it extends pastthe outer wall of the house.

Fascia:A flat board, band or face locatedjust below the eave.

Flashing:Pieces of metal used to preventwater seepage around any intersec-tion or projection in a roof, such asvent pipes, chimneys, valleys andthe joints at vertical walls.

A Homeowner’s Guide to Roofing and Hail

terms you should knowWhether you’re considering roofing options or just doing routine maintenance,it’s important to know your way around. Here’s a brief lesson in roofing anatomy.

The basic components of a roof system.

11

Louvers:Slatted devices installed in a gableend wall or in a soffit (the undersideof the eaves) to ventilate the spacebelow the roof deck and equalize airtemperature and moisture.

Rake:An extension of the roof over awall at the gable end.

Ridge:The top edge of two intersectingsloping roof surfaces.

Slope:Slope is measured by rise in inchesfor each 12 inches of horizontalrun. A roof with a 4-in-12 sloperises 4 inches for every horizontalfoot, for instance. The steeper theslope, the more difficult the repairand more costly the labor.

Square:The most common measurementfor roof surfaces, it equals 100square feet (10’x10’).

Underlayment/Felt:A sheet of asphalt-saturated mater-ial (often called “tar paper”) usedas a secondary layer of protectionfor the roof deck. It is rolled out ontop of the roof deck and sits underthe roof covering.

Valley:The angle formed at the intersec-tion of two sloping roof surfaces.

Vapor Retarder:A material designed to restrict thepassage of water vapor through aroof or wall.

terms you should know

Graphics and text in cooperationwith the National RoofingContractors Association.

12A Homeowner’s Guide to Roofing and Hail

APA — The EngineeredWood Association (APA)

PO Box 11700Tacoma, WA 98411-0700Tel: 253-565-6600Fax: 253-565-7265http://www.apawood.org/

American Society of HomeInspectors (ASHI)

932 Lee Street, Suite 101Des Plaines, IL 60016Tel: 800-743-2744Fax: 847-759-1620http://www.ashi.com/

Asphalt RoofingManufacturers Association(ARMA)

1156 15th Street, N.W.Suite 900Washington, DC 20005Tel: 202-207-0917Fax: 202-223-9741http://www.asphaltroofing.org/

Building Officials & CodeAdministrators, International,Inc. (BOCA)

4051 West Flossmoor RoadCountry Club Hills, IL 60478-5795Tel: 708-799-2300Fax: 708-799-4981http://www.bocai.org/

Cedar Shake & ShingleBureau (CSSB)

P.O. Box 1178Sumas, WA 98295Tel: 604-820-7700Fax: 604-820-0266http://www.cedarbureau.org/

Institute for Business &Home Safety (IBHS)

4775 E. FowlerTampa, FL 33617Tel: 1-866-657-4247Fax: 813-286-9960http://www.ibhs.org

International Code Council(ICC)

5203 Leesburg Pike, Suite 600Falls Church, VA 22041Tel: 703-931-4533Fax: 703-379-1546http://www.intlcode.org

International Conference ofBuilding Officials (ICBO)

5360 Workman Mill RoadWhittier, CA 90601-2298Tel: 562-699-0541http://www.icbo.org

additional sources ofinformation

13additional sources of information

International ResidentialCode (IRC)

5203 Leesburg Pike, Suite 600Falls Church, VA 22041Tel: 703-931-4533Fax: 703-379-1546http://www.intlcode.org

Metal BuildingManufacturers Association(MBMA)

1300 Summer AvenueCleveland, OH 44115-2851Tel: 216-241-7333Fax: 216-241-0105http://www.mbma.com/

National Association ofHome Builders (NAHB)

1201 15th Street, N.W.Washington, DC 20005Tel: 202-822-0200Fax: 703-243-3465http://www.nahb.com/

National Association of theRemodeling Industry

4301 North Fairfax DriveSuite 310Arlington, VA 22203http://www.nari.org/

National RoofingContractors Association(NRCA)

10255 West Higgins RoadSuite 600Rosemont, IL 60018Tel: 847-299-9070Fax: 847-299-1183http://www.nrca.net/

National Tile RoofingManufacturers Association(NTRMA)

PO Box 40337Eugene, OR 97404-0049Tel: 541-689-0366Fax: 541-689-5530http://ntrma.org/index.htm

Southern Building CodeCongress International, Inc.(SBCCI)

900 Montclair RoadBirmingham, AL 35213-1206Tel: 205-591-1853Fax: 205-592-7001http://www.sbcci.org/

A Homeowner’s Guide to Hurricane Retrofit

©2002 IBHS

4775 E. Fowler Ave. • Tampa, FL 336171(866) 657-4247(IBHS) • Fax: (813) 286-9960 • www.ibhs.org