TEXAS RESIDENTIAL ROOFS

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1 INSURANCE INSTITUTE FOR BUSINESS & HOME SAFETY BEST PRACTICES GUIDE Use this guidance to improve the long-term performance of your rf.

2 In the spring of 2016, severe storms ripped through Texas, substantially damaging more than 10,000 residential and commercial rfs. The rf is every building s first line of defense against Mother Nature, and is also the most vulnerable system in a home. With more frequent extreme weather events continuing to hit Texas every year, your rf could sustain costly damage requiring repairs or even replacement. IBHS is providing this guide for homeowners to use when repairing or replacing rfs. Following the recommendations in this guide will improve the long-term performance of your rf. IBHS guidelines help owners improve their home s ability to resist damage from thunderstorms, winds at the edge of tornadoes, hail events, and hurricanes. Implementing these guidelines when building, replacing, repairing or retrofitting a residential rf will make your home a more resilient and durable asset. Approved products provide a known performance, so IBHS recommends the use of products that have been tested and approved by a certified testing facility. Product approvals in Texas can be found at wind/prod/index.html. Also included in this guide is information about selecting a qualified rfing contractor. Proper installation directly impacts a rf s long-term performance so it is important to chse the right contractor. Take the time to check the contractor s references and their insurance coverage, and talk to the contractor about your expectations. BEST PRACTICES GUIDE 2

3 Rfing the Right Way Implementing the recommendations in this guide when building, replacing, repairing or retrofitting a residential rf will make the building a more resilient and durable asset by improving the long-term performance of your rf during severe weather events. Remove tree branches that overhang the rf To prevent damage from branches rubbing or falling on the rf, remove branches that overhang the rf and trim them back away from the rf. Remove existing rf cover Remove the existing rf cover and underlying building paper or underlayment to expose the rf deck. This allows strengthening of the connections between the rf deck and rf structure. It also provides a solid, smth surface needed to help ensure the new rf cover achieves its full strength. Inspect for damage Lk at the rf deck for rotting, delaminating, warping or other signs it may be structurally unsound. If any of these signs exist, replace damaged sections with similar materials of the same thickness. More specific detailed guidance is available in the IBHS FORTIFIED Home standards. Re-nail the rf deck Install additional fasteners as needed to provide a more wind-resistant connection of the rf deck to the rf framing. More specific guidance is outlined below. Anchor gable end outlkers Outlkers are rf framing members that are sometimes used to support the rf overhang at the gable end of a house. They start at the second truss or rafter back from the gable end wall and extend out over the gable end wall framing to support the edge of the rf. Improve the anchorage by connecting outlkers to the rf framing with metal brackets or straps. More specific detailed guidance is available in the IBHS FORTIFIED Home standards. any location where the rf changes slope. At eaves and gable rakes, the flashing is called a drip edge. Valley areas without flashing are especially vulnerable to leakage. Installation of a 36-in.-wide self-adhered polymer-modified bitumen membrane underlayment or metal flashing centered on the valley is critical. At intersections of the rf with vertical surfaces, such as walls and chimneys, the flashing should extend up the vertical surface, be covered with wall cladding and lapped in shingle fashion. A corrosion-resistant drip edge should be provided at eaves and gables of shingle rfs. The overlap between sections of drip edge metal should be at least 3 in. and drip edges should extend ½ in. below sheathing and extend back on the rf a minimum of 2 in. Drip edge should be fastened to the rf deck at 4 in. o.c. Apply an approved rf cover Apply an approved high-wind and impact-resistant rf cover. Follow the manufacturer s installation instructions for high-wind areas or local code requirements, if they are more restrictive. More specific guidance for asphalt shingles, tile and metal systems is provided below. Install and attach rf vents All rf vents should be properly installed and attached to the rf deck in accordance with the manufacturer s recommendations and building code ventilation requirements. Vents that have passed Florida Building Code Test Standard TAS 100 (A) are tested for both high winds and water intrusion. Seal the rf deck against water intrusion This will help keep water out of the house if the rf cover blows off. Large amounts of wind-driven rain can pour into the attic through unsealed gaps between pieces of rf sheathing. Options for sealing the rf deck are outlined below. Install flashing Proper flashing is important to the performance of your rf. Flashing is necessary at all penetrations, including pipes and vents that create openings in the rf deck; where the rf intersects with vertical surfaces, such as walls of an upper story or chimneys; in valleys and at Retrofit or replace vulnerable soffits Make sure they are installed according to manufacturer s instructions. Most aluminum and vinyl soffit high-wind installations require an intermediate support when the soffit extends more than 12 in. from the wall. When soffit covers are blown out during a hurricane, a tremendous amount of water can enter the attic. It is important to make sure the soffit material stays in place. BEST PRACTICES GUIDE 3

4 Rf Deck RE-NAILING THE ROOF DECK IBHS research has found that the use of staples and minimum size nails allowed in older building codes, regardless of the spacing, are inadequate to keep a rf from lifting up in high winds. This is particularly true along trusses and rafters in the middle of the rf sheathing panels, where it has been common practice to space fasteners 12 in. apart. When an old rf cover and underlayment is torn off, it s easy to inspect the existing fasteners and to install additional nails to strengthen the rf deck attachment. IBHS recommends installing ring shank nails, if additional nails are required to strengthen the rf deck attachment. Generally, if nails fastening the rf deck to the rf framing below are smaller than 8d common nails or if staples were used, 8d ring shank nails should be added at 6 in. o.c. If the size of the existing nails is at least 8d commons, the distance between nail spacing should not exceed 6 in. o.c. If it does, 8d ring shank nails should be added to reduce the nail spacing so the distance between the existing nails and the additional nails is no more than 6 in., unless engineering analysis or local code requires more fasteners at the corners. SEALING THE ROOF DECK AGAINST WATER INTRUSION The rf deck should be sealed to prevent water intrusion. Typical felt underlayment is not sufficient. The following options provide more specific information on underlayment systems that seal the rf deck. Option 1 Tape rf seams between rf sheathing. There are two material options for taping the seams on the rf deck. Option 1: Apply an ASTM 1970 compliant self-adhering polymer-modified bitumen flashing tape, at least 4 in. wide, directly to the rf deck to seal the horizontal and vertical joints in the rf deck. Option 2: Apply an AAMA , Level 3 (for exposure up to 80 C/176 F) compliant self-adhering flexible flashing tape, at least 3¾ in. wide, directly to the rf deck to seal the horizontal and vertical joints in the rf deck. All flashing tape used to achieve a sealed rf deck should be fully adhered without voids (e.g., wrinkles). Do not nail or staple the tape to the rf sheathing. Refer to the manufacturer s requirements for installation as some tapes may require installation over primer. Next, apply a code-compliant #30 ASTM D226 Type II underlayment over the self-adhering tape. This underlayment should be attached using annular ring or deformed shank rfing fasteners with minimum 1-in.-diameter caps (button cap nails) at 6 in. o.c. spacing along all laps and at 12 in. o.c. in the field or a more stringent fastener schedule if required by the manufacturer for high-wind installations. Horizontal laps should be a minimum of 2 in. and end laps should be a minimum of 6 in. Option 2 Cover the entire rf deck with a full layer of selfadhering polymer-modified bitumen membrane meeting ASTM D1970 requirements. Cover the membrane with a layer of #15 ASTM D226 Type I underlayment over the fully adhered membrane as a bond break when the rf cover is asphalt shingles. Option 3 Apply a reinforced synthetic rf underlayment which has an ICC approval as an alternate to ASTM D226 Type II felt paper. The synthetic underlayment should have minimum tear strength of 20 lb per ASTM D5034 or ASTM D4533. This underlayment should be attached using annular ring or deformed shank rfing fasteners with minimum 1-in.-diameter caps (button cap nails) at 6 in. o.c. spacing along all laps and at 12 in. o.c. in the field or a more stringent fastener schedule if required by the manufacturer for high-wind installations and prolonged exposure. Horizontal laps should be a minimum of 2 in. and end laps shall be 6 in. and all laps should be sealed with a compatible tape or mastic. If horizontal laps are increased to 19 in., they do not need to be sealed with tape or mastic. All vertical seams need to be appropriately sealed. Option 4 Install two (2) layers of ASTM D 226 Type II (#30) or ASTM D 4869 Type IV (#30) underlayment in a shingle-fashion, lapped 19 in. on horizontal seams (36-in. roll), and 6 in. on vertical seams. Fasten underlayment at approximately 6 in. o.c. along the laps and at approximately 12 in. o.c. in the field of the sheet between the side laps. Secure underlayment using annular ring or deformed shank nails with 1-in.-diameter caps (button cap nails). BEST PRACTICES GUIDE 4

5 Shingles CHOOSING AND INSTALLING HIGH WIND RATED SHINGLES The ASTM shingle testing standards and classification system, not the advertised warranty period and warranty wind speed for the shingles, will determine which shingles are best suited for the wind speeds in your area. For optimal protection from high wind, chse shingles that have an ASTM D7158 Class H or ASTM D3161 Class F wind rating. For improved hail protection, select a product that has a UL 2218 or FM 4473 Class 4 impact rating. Note: If you live in a wildfire-prone area, make sure the shingles also include a UL or ASTM Class A fire rating. Asphalt shingles, along with tile and metal rf coverings, are widely available with a Class A fire rating. Shingles should be installed in accordance with the manufacturer s instructions for high-wind installation, using the number of nails in the locations required by the manufacturer for high-wind fastening. In areas where the local building code requires more fasteners than are required by the manufacturer, fasteners should comply with the local building code. ASPHALT SHINGLE IMPACT- RESISTANCE STANDARDS UL 2218 is a test standard developed by Underwriters Laboratories for assessing the impact resistance of flexible rfing products. Testing involves dropping steel balls of varying sizes from heights designed to simulate the energy of falling hailstones. Class 4 indicates the product was still functional after being struck twice in the same spot by 2-in. steel balls. Note: This standard is appropriate for flexible rfing products like asphalt shingles. Class 4 rated products should be used. CLAY AND CONCRETE ROOF TILES Clay and Concrete Tile Wind-Resistance Requirement Clay and concrete rf tile systems and their attachment must meet the requirements for the site design wind speed and exposure category. Clay and concrete rf tiles must be installed in accordance with FRSA/Tile Rfing Institute installation guidelines, Concrete and Clay Rf Tile Installation Manual Fifth Edition Revised, for the site design wind speed and exposure. For high-wind consideration, a minimum 110 mph Vasd/140 mph Vult is appropriate. Hip and ridge boards must be attached to the rf framing to resist the uplift pressure in accordance with the FRSA/TRI Manual using the appropriate site design wind speed or the 110 mph Vasd/140 Vult minimum. Hip and ridge tiles must be secured to the hip and ridge boards with mechanical fasteners and/or an approved rf tile adhesive. Note: FRSA/Tile Rfing Institute installation guidelines, Concrete and Clay Rf Tile Installation Manual Fifth Edition, Revised, are available from the Tile Rfing Institute or the Florida Rfing, Sheet Metal and Air Conditioning Contractor s Association. Tile Impact-Resistance Standards FM 4473 is a test standard administered by FM Approvals and is a test that is similar to UL 2218, but instead of using steel balls, frozen ice balls are used. The FM 4473 test standard is used on rigid rf covering materials (like concrete tile, clay tile, or slate) and involves firing the ice balls from a sling or air cannon at the rf-covering product. A Class 3 rating indicates the product was still functional after being struck twice in the same spot by a 1¾-in. ice ball; a Class 4 rating requires the product to still be functional following 2 impacts in the same spot with 2-in. ice balls. Clay and concrete rf tiles should meet either a Class 3 or Class 4 impact rating. Class 4 rated products are preferred. METAL PANELS Metal Rf Wind-Resistance Requirement Metal panel rfing systems and their attachment must be installed in accordance with the manufacturer s installation instructions and must provide uplift resistance equal to or greater than the design uplift pressure for the rf based on the site design wind speed and exposure. For highwind consideration, a minimum 110 mph Vasd/140 mph Vult is appropriate. The metal panels must be installed over continuous decking and one of the acceptable sealed rf deck underlayment options. Metal Rf Impact-Resistance Standards The UL 2218 standard is appropriate for flexible rfing products like metal panels or metal shingles. Class 4 rated products should be used. It should be noted that while impact-resistant metal rfs have gd impact resistance and are likely to survive hailstones without functional damage, metal rfs can be vulnerable to aesthetic damage since hail can cause permanent indentations in the rfing panels. Use of metal rfing products with granular coatings may reduce the visibility of small indentations. BEST PRACTICES GUIDE 5

6 GUIDELINES FOR ROOFING IN WILDFIRE-PRONE AREAS Texas is at high risk for wildfire with many homes located in what the fire service calls the Wildland Urban Interface (WUI), which can include suburban areas with designated conservation/ preservation areas in and around the complexes. This type of land use planning can create increased exposure to wildfire, especially in typically dry and drought-stricken areas. While direct exposure to wildfire flames and radiant heat can be a source of ignition, burning embers associated with wildfires can travel significant distances and land on rfs or be blown into vents, resulting in ignition of the building. To help prevent fire damage to your rf, you should first assess your rfing material to determine your risk. If necessary, consider replacing your rf using fire-resistant rfing material. How Fire Resistant is Your Current Rf? The fire rating of a rf covering is either Class A, Class B, Class C, or unrated. An unrated rf covering is the most vulnerable the most common example of an unrated rf covering is one made using non-fire-retardanttreated wd shakes or shingles. Class A is the most fire resistant and should be the first choice of anyone living in wildfire-prone areas. Common Class A rf coverings include asphalt fiberglass composition shingles and concrete or clay tiles. Some materials have a by assembly Class A fire rating, meaning additional materials should be used between the rf covering and the rf sheathing in order to attain the fire rating. Examples of rf coverings with a by assembly fire rating include aluminum, some fire-retardant wd shake products, and recycled plastic and rubber products. If you have a wd shake rf and do not have, or cannot find, documentation from the manufacturer that specifies the fire retardant, assume it is untreated. If you are not sure, or want to confirm your rf type, schedule a rf inspection by a rfing professional (See below for how to hire a reputable rfing contractor). If your home is located in a wildfire-prone area and your rf needs to be repaired or replaced, IBHS recommends you install a Class A fire-rated rf. How to Hire a Residential Rfing Contractor This checklist is intended to help you make informed decisions about chsing a dependable rfing contractor with a track record for ethical business practices and quality work. 99Lk for well-established, insured rfing professionals with a federal tax identification number and a permanent address. 99Ask to see the company s certificates of insurance. Make sure its coverage for liability and workers compensation insurance is current. 99Contact the National Rfing Contractors Association (NRCA) to use their Find a Contractor tl. The NRCA provides continuing education and up-to date information about rfing trends and developments for its members. 99Contact the Better Business Bureau in your area to check for complaints filed against any company you are considering hiring. 99Get more than one estimate. 99Require references that specifically include other homes in your area, and check them. 99Get everything in writing including total cost, specific work to be completed, project schedule, guarantees, payment terms and other expectations should be detailed. Anything you sign will be considered a binding contract. 99Pay close attention to material warranties from the rf manufacturer and installation warranties from the contractor and lk at what they do and don t include, particularly what is contained in the Terms, Conditions, and Limitations section, which may reference specific wind speeds, types of weather or Acts of God. 99Don t be pushed into signing a contract right away. Never sign a contract with blanks fraudulent contractors may enter unacceptable terms later. 99Make sure you review and understand all documents sent to your insurance carrier. 99Never pay a contractor in full or sign a completion certificate until all the work is completed. BEST PRACTICES GUIDE 6

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