Roofing Education 101

Most people are not aware of what is going on under their shingles and honestly some of us couldn’t even choose what we have. Most roofs haven’t had a proper system installed causing their roofs to deteriorate prematurely and so many other related issues, so it’s time for you to get well inform and to make that big investment worth it.
We will share with you….
Having a layer of underlayment provides extra protection between your shingles and your roof deck (wood), which is why choosing the right one is very important and believe us, it makes a big difference.
Typically in most roofs you will find a 15 lb. or 30 lb. black felt, an asphalt-saturated sheet, this product is basically a thick paper felt, that usually absorb moisture that leads to wrinkling, becomes brittle and could leach oils.
This felt you can easily torn or wrinkle with your own hands with out taken his original state completely back, if something like that happens during your installation you will end up with a bumpy roof, since the waves in the felt will transfer to your shingles ending up in a non good looking roof.
A high quality roofing system uses a synthetic felt(called FeltBuster for GAF product / ProArmor for Owens Corning product)
Synthetic products are manufactured from polypropylene and polyethylene. Synthetic underlayments offer a variety of advantages over the roofing felt, such as tear resistance, UV resistance, and they don’t wrinkle when exposed to moisture like roofing felt does.
Other advantages of working with a synthetic felt are:

• Long lasting performance: This will last for years with out disintegrating under your shingles, like felts does. Your roof could be left with only the synthetic underlayment (and a few other products we will talk about later) with no shingles on for 90 days and you won’t have water coming in
• Its surface provides a more stable and a cooler walking area
• Resist tearing
• Avoids wrinkling that can be transfer to the finish look of your roof
• Felt stretching around nails or fasteners as called in the roofing industry are minimum, preventing possible water penetration to your roof deck
• It works great in high pitched roof

An other important component that your roof should have is a leak barrier.
In regions where snow and ice are pretty common during the winter months, having an ice and water shield in addition to roofing felt makes a watertight and energy efficient covering for the roof.
There is a mineral-surfaced leak barrier and a film surfaced leak barrier.
The mineral-surfaced is a fiberglass mat-reinforced membrane with mineral fines on the top surface and the film surface leak barrier is a fiberglass mat-reinforced but this one has a membrane with a polymeric film on the top.
Both membranes help prevent leaks caused by roof settling, wind-driven rain and ice dams on the most vulnerable areas of your roof which are your eaves, rakes, your valleys, around the chimney, sky windows, pluming vents among others.
Although both products have really good qualities protecting your roof like:

• Waterproof barrier
• Tear resistance
• Self-adhesive: it adheres to the deck and seal around fasteners to prevent water penetration
• Slip-resistance surface for traction and save installation

The film surface leak barrier also has:

• Resist UV degradation
• His slip-resistance is greater because of its polyester surface provides more traction
• And as we mention previously it could be left exposed for up to 90 days and you won’t have water coming in

Once you have your deck and vulnerable areas protected you must think that is time to shingle, but we still have some important steps to cover.
Drip edge: you must have them installed on your roof, it should go on your eves and rakes, this will prevent water to roll back to your deck, which will absorb the water and rod.
Starter Strip: back in time what roofers used to do at the edge of roofs was to turn a 3-tap shingle backwards; the problem is, this shingle wasn’t designed for this purpose and a lot of roofs were installed with them.
Starter Strip shingle is a long, usually made of asphaltic material strip that goes at the edge of the roof, it comes with a line of adhesivewhich bonds with the shingle placed above and seal them down protecting them from the elements, a 3-tap shingle doesn’t have this adhesive so with out a proper starter strip, a gust of wind could blow them off or wind blow rain could get beneath those shingles that aren’t sealed down.
Some roofers claim you don’t need a start strip shingle, but actually installing them provides you that crucial extra layer of protection.
Now, shingles, there is a huge variety out there, different shapes, materials, colors, thickness, quality, you name it, so which one to choose?
You will choose that beautiful color and shingle design that will make your house to stand out in your neighborhood and of course the one that best works for your specific needs, however there are a 2 other important things to look for in a shingle.
A standard roof installation requires 4 nails per shingle, however, in order to provide a high wind resistance roof an enhanced nailing pattern of 6 nails are used instead to allow enough hold against the elements and prevent shingles to blow off the roof.
A really good shingle is one that allows an efficient installation as well, many brands doesn’t show the workers where a nail should be in order to obtain the maximum benefic out of the product, but “they should know where, right?” lets think about it for a moment, 6 nails per shingle in a whole roof, that could mean thousands of nails so that means there could be a possibility that they don’t hit the target a 100% of the times and lets not take this lightly, if a shingle gets nail lower or above an specific area, that  could jeopardize its integrity causing  weak spots that could lead into leaking or even the shingle to blow off the roof.
Owens Corning a shingle manufacturer company has actually incorporated in their shingles a woven-fabric nailing stripthat enhance its performance by helping deliver a 130-MPH wind warranty and provides an easy to see, strong and durable nailing zone, so workers don’t have to guess.
Another important feature to look for in a shingle is thermal sealant on the back, this will help the shingles that are on top of each other to firmly bond together, covering the nails as well, protecting them from corrosion.
So, we just picket out the perfect shingle, what is the next step?
A good roof vents means a healthy home and is crucial in roof design since it will provide a proper attic ventilation which helps prevent early aging to your roofing materials, moderates the attic temperature and prevents moisture to grow in your attic.
There are different types of vents but which one works best?
 

• Box vents: work better when used with soffit ventilation, they are designed to work with open attics, they are placed on the sides of your roof and you will usually need more than one to remove all the hot air from your attic.
• Soffit vents: these are installed in the soffits and allow air to flow up under the roof and into the attic.
• Turbine vents: These vents use the wind and air pressure to spin and vent out stale air.
• Eyebrow vent: They provide curved openings on roof slopes and they are used in pairs on each side of the roof to provide air movement.
• All the vents mentioned above are placed on the sides of the roof not at the very top and this could mean that all the hot air trapped at the highest point of your roof is not been vent out properly.
• There is the Ridge vent: The advantage of this type of vent over traditional rectangular vents (mention before) is the coverage over the entire upper portion of the attic instead of a few isolated locations, allowing continuous air flow along the entire ridge, where hot air and moist typically builds up. You will mostly see 2 types: Metal and Shingle over ridge
  • Metal ridge vents are susceptible to more condensation with temperature changes, leading to moss growing around metal roof vents and it also mean that the metal will start to corrode and rust leading to leaking because of all the exposed nail (they go right through the surface of the vent and into the roof)
  • Shingle over shingle:Most of these vents are now made of a tough polypropylene blend and generally are better designed than older aluminum models giving them a long lasting durability. This are designed with an interior baffle that allows air to flow out and also protects your attic from the elements. Once the ridge vent is nailed into place, shingles are place over top covering the nails.

Again, most roofers use a 3-tap shingle to cover the ridge vent and once again this shingles weren’t designed for this purpose, which is why GAF and Owens Corning have a specialized Hip & Ridge Cap Shingle, this product is much thicker that a regular shingle and it was made to bend according to the pitch of your roof with out cracking as a 3-tap shingle would do, the cap shingle will also have a thermal sealant so they will bond together and this will insure you that your nails won’t be exposed and your cap shingle won’t be tear off your roof.
Last but not least, Pipe jacks. When a homeowner contacts a roofing company for leak problems 7 out of 10 times the leak is happening around the pipe boot. Whether is it that a new roof it’s going to be installed or just replacing a pipe jack you need to know that what goes on your roof it’s a high quality product.
Lets talk about standard pipe jacks shall we?

• You, as a consumer can find them anywhere, at any local supplier store actually.
• These pipe jacks are made of plastic and contains a multi-size elastomer collar that accommodates different vent pipe sizes, one product fits them all, the problem is in order to fit your specific size of boot they have to cut the collar manually forcing who ever is making the installation to use caulk around it to seal it, this may last a couple of years however the caulk deteriorates and eventually water will come in.
• The collar doesn’t have any flexibility to give on the slope of your roof leaving a gap between the boot and the pipe, another reason why they caulk it.
• In most of these products the installation required to nail the plastic vent pipe flashing on specific areas leaving expose nails that will corrode exposing your home to water.
• An other important fact, did you know that the roof moves? Yes, it does! The roof will expand during summer time because of high temperatures and will contract during winter because of low temperatures so you need a product that does it too other wise the nails will damage that plastic flashing making a big hole and once again… water will come in.

Now, lets talk about an Ultimate Pipe Flashing the name says it all but lets elaborate:

• This product is not available at your local home improvement stores, only a few supplier distributers carry them.

·      This pipe jacks has a Kynar PVDF coated 24 gauge galvanized sheet metal plate. PVDF is a a specialty plastic used in applications requiring the highest purity, and because of its purity, it also offer resistance to abrasion, impact resistance, thermal stability, making it the ideal choice for the development of highly durable and substantially lighter materials.

• Its collar is made of ultra-pure silicone, which provides UV/Ozone stability and it also contours to the slope of your roof, so, no gap between your pipe and your boot.
• Its custom fit, that means no cuts to fit your boot and no caulking to seal it, there is one for your specific boot size.
• Its nailing slots are specially designed so your pipe jack can move with your roof as seasons change and to guaranty you that no nails will be exposed.

All this features will give you a lifetime tool, so which one would you rather have on your roof?
So, now that you know what should be on your roof, don’t hesitate to demand the best products out there and we at Daniel Hood Roofing Systems will provide you the highest quality in service you can experience on any home project.
By Deborah Ogle
 
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We are proud to be a new member of the United Association of Storm Restoration.
Certificate of Membership
Member Since—2017 
Daniel Hood Roofing Systems 
Is a proud member of the United Association of Storm Restoration Contractors, a voluntary commitment to excellence. As a member they have agreed to abide by a code of conduct that includes strict ethical standards which is demanded of all UASRC members.
Jacob Sachs
Executive Director, UASRC
MEMBERSHIP CERTIFICATE 2017 – Daniel Hood Roofing

This article is provided by the National Roofing Contractors Association (NRCA) in an effort to educate home and building owners about roofing and roofing contractors.
We hope this information will make you a more knowledgeable consumer and, when the time comes, a smart roof system buyer.
A new roof system is a big investment. We want to help you get a quality roof system at a fair price from a professional roofing contractor.
William A. Good, CAE
Executive Vice President
National Roofing Contractors Association
Roof system components
All steep-slope roof systems (i.e., roofs with slopes of 25 percent or more) have five basic components

1. Roof covering: shingles, tile, slate or metal and underlayment that protect the sheathing from weather.
2. Sheathing: boards or sheet material that are fastened to roof rafters to cover a house or building.
3. Roof structure: rafters and trusses constructed to support the sheathing.
4. Flashing: sheet metal or other material installed into a roof system’s various joints and valleys to prevent water seepage.
5. Drainage: a roof system’s design features, such as shape, slope and layout that affect its ability to shed water.

Choosing a roof system
There are a number of things to consider when selecting a new roof system. Of course, cost and durability head the list, but aesthetics and architectural style are important, too. The right roof system for your home or building is one that balances these five considerations. The following roofing products commonly are used for steep-slope structures.
Asphalt shingles possess an overwhelming share of the U.S. steep-slope roofing market and can be reinforced with organic or fiberglass materials. Although asphalt shingles reinforced with organic felts have been around much longer, fiberglass-reinforced products now dominate the market.
Organic shingles

Fiberglass shingles

Asphalt shingles’ fire resistances, like most other roofing materials, are categorized by Class A, B or C. Class A signifies the most fire-resistant; Classes B and C denote less fire resistance. Generally, most fiberglass shingles have Class A fire ratings, and most organic shingles have Class C ratings.
A shingle’s reinforcement has little effect on its appearance. Organic and fiberglass products are available in laminated (architectural) grades that offer a textured appearance. Zinc or copper-coated ceramic granules also can be applied to organic or fiberglass products to protect against algae attack, a common problem in warm, humid parts of the United States. Both types of shingles also are available in a variety of colors.
Regardless of their reinforcing type and appearance, asphalt shingles’ physical characteristics vary significantly. When installing asphalt shingles, NRCA recommends use of shingles that comply with American Society for Testing and Materials (ASTM) standards-ASTM D 225 for organic shingles and ASTM D 3462 for fiberglass shingles. These standards govern the composition and physical properties of asphalt shingles; not all asphalt shingles on the market comply with these standards. If a shingle product complies with one of these standards, it is typically noted in the manufacturer’s product literature and on the package wrapper.
Wood shingles and shakes are made from cedar, redwood, southern pine and other woods; their natural look is popular in California, the Northwest and parts of the Midwest. Wood shingles are machinesawn; shakes are handmade and rougher looking. A point to consider: Some local building codes limit the use of wood shingles and shakes because of concerns about fire resistance. Many wood shingles and shakes only have Class C fire ratings or no ratings at all. However, Class A fire ratings are available for certain wood shingle products that incorporate a factory-applied, fire-resistant treatment.
Tile—clay or concrete—is a durable roofing material. Mission and Spanish-style round-topped tiles are used widely in the Southwest and Florida, and flat styles also are available to create French and English looks. Tile is available in a variety of colors and finishes. Tile is heavy. If you are replacing another type of roof system with tile, you will need to verify that the structure can support the load.
Slate is quarried in the United States in Vermont, New York, Pennsylvania and Virginia. It is available in different colors and grades, depending on its origin. Considered virtually indestructible, it is, however, more expensive than other roofing materials. In addition, its application requires special skill and experience. Many old homes, especially in the Northeast, still are protected by this long-lasting roofing material.
Metal, primarily thought of as a low-slope roofing material, has been found to be a roofing alternative for home and building owners with steep-slope roofs. There are two types of metal roofing products: panels and shingles. Numerous metal panel shapes and configurations exist. Metal shingles typically are intended to simulate traditional roof coverings, such as wood shakes, shingles and tile. Apart from metal roofing’s longevity, metal shingles are relatively lightweight, have a greater resistance to adverse weather and can be aesthetically pleasing. Some have Class A fire ratings.
Synthetic roofing products simulate various traditional roof coverings, such as slate and wood shingles and shakes. However, they do not necessarily have the same properties.
Before making a buying decision, NRCA recommends that you look at full-size samples of a proposed product, as well as manufacturers’ brochures. It also is a good idea to visit a building that is roofed with a particular product.
Ventilation and insulation are key
One of the most critical factors in roof system durability is proper ventilation. Without it, heat and moisture build up in an attic area and combine to cause rafters and sheathing to rot, shingles to buckle, and insulation to lose its effectiveness.
Therefore, it is important never to block off sources of roof ventilation, such as louvers, ridge vents or soffit vents, even in winter. Proper attic ventilation will help prevent structural damage caused by moisture, increase roofing material life, reduce energy consumption and enhance the comfort level of the rooms below the attic.
In addition to the free flow of air, insulation plays a key role in proper attic ventilation. An ideal attic has:

• A gap-free layer of insulation on the attic floor to protect the house below from heat gain or loss
• A vapor retarder under the insulation and next to the ceiling to stop moisture from rising into the attic
• Enough open, vented spaces to allow air to pass in and out freely.
• A minimum of 1 inch between the insulation and roof sheathing.

The requirements for proper attic ventilation may vary greatly, depending on the part of the United States in which a home or building is located, as well as the structure’s conditions, such as exposure to the sun, shade and atmospheric humidity. Nevertheless, the general ventilation formula is based on the length and width of the attic. NRCA recommends a minimum of 1 square foot of free vent area for each 150 square feet of attic floor—with vents placed proportionately at the eaves (e.g., soffits) and at or near the ridge.
Even roofs have enemies
A roof system’s performance is affected by numerous factors. Knowing about the following will help you make informed roof system buying decisions:

• Sun: Heat and ultraviolet rays cause roofing materials to deteriorate over time. Deterioration can occur faster on the sides facing west or south.
• Rain: When water gets underneath shingles, shakes or other roofing materials, it can work its way to the roof deck and cause the roof structure to rot. Extra moisture encourages mildew and rot elsewhere in a house, including walls, ceilings, insulation and electrical systems.
• Wind: High winds can lift shingles’ edges (or other roofing materials) and force water and debris underneath them. Extremely high winds can cause extensive damage.
• Snow and ice: Melting snow often refreezes at a roof’s overhang where the surface is cooler, forming an ice dam. This blocks proper drainage into the gutter. Water backs up under the shingles (or other roofing materials) and seeps into the interior. During the early melt stages, gutters and downspouts can be the first to fill with ice and be damaged beyond repair or even torn off a house or building.
• Condensation: Condensation can result from the buildup of relatively warm, moisture-laden air. Moisture in a poorly ventilated attic promotes decay of wood sheathing and rafters, possibly destroying a roof structure. Sufficient attic ventilation can be achieved by installing larger or additional vents and will help alleviate problems because the attic air temperature will be closer to the outside air temperature.
• Moss and algae: Moss can grow on moist wood shingles and shakes. Once it grows, moss holds even more moisture to a roof system’s surface, causing rot. In addition, moss roots also can work their way into a wood deck and structure. Algae also grows in damp, shaded areas on wood or asphalt shingle roof systems. Besides creating a black-green stain, algae can retain moisture, causing rot and deterioration. Trees and bushes should be trimmed away from homes and buildings to eliminate damp, shaded areas, and gutters should be kept clean to ensure good drainage.
• Trees and leaves: Tree branches touching a roof will scratch and gouge roofing materials when the branches are blown by the wind. Falling branches from overhanging trees can damage, or even puncture, shingles and other roofing materials. Leaves on a roof system’s surface retain moisture and cause rot, and leaves in the gutters block drainage.
• Missing or torn shingles: The key to a roof system’s effectiveness is complete protection. When shingles are missing or torn off, a roof structure and home or building interior are vulnerable to water damage and rot. The problem is likely to spread-nearby shingles also are ripped easily or blown away. Missing or torn shingles should be replaced as soon as possible.
• Shingle deterioration: When shingles are old and worn out, they curl, split and lose their waterproofing effectiveness. Weakened shingles easily are blown off, torn or lifted by wind gusts. The end result is structural rot and interior damage. A deteriorated roof system only gets worse with time-it should be replaced as soon as possible.
• Flashing deterioration: Many apparent roof leaks really are flashing leaks. Without good, tight flashings around chimneys, vents, skylights and wall/roof junctions, water can enter a home or building and cause damage to walls, ceilings, insulation and electrical systems. Flashings should be checked as part of a biannual roof inspection and gutter cleaning.

Choosing a contractor
Buying a new roof system is an important investment. Before you spend your money, spend time learning how to evaluate roofing contractors. You should insist on working with a professional roofing contractor. NRCA wants to assist you in getting the kind of results you expect—a quality roof system at a fair price. All roofing contractors are not alike, and NRCA recommends that you prequalify roofing contractors to get the job done right the first time. The following guidelines will help you select a professional:

• Check for a permanent place of business, telephone number, tax identification number and, where applicable, a business license.
• Don’t hesitate to ask a roofing contractor for proof of insurance. In fact, insist on seeing copies of his liability coverage and workers’ compensation certificates. (U.S. workers’ compensation laws vary by state. Consult your state’s laws to determine workers’ compensation insurance requirements.) Make sure the coverages are in effect through the duration of the job. Many building and home owners have been dragged into litigation involving uninsured roofing contractors. Also, if a contractor is not properly insured, you may be liable for accidents that occur on your property.
• Check to see if the roofing contractor is properly licensed or bonded. Some states have specific licensing requirements, and others do not. Your state’s Department of Professional Regulation or Licensing Board will have this information.
• Make sure the contractor is financially stable. A professional roofing contractor can provide current financial information about his company.
• Look for a company with a proven track record that offers client references and a list of completed projects. Call these clients to find out whether they were satisfied.
• Insist on a detailed, written proposal and examine it for complete descriptions of the work and specifications, including approximate starting and completion dates and payment procedures.
• Have the contractor list the roofing manufacturers with which his firm is a licensed or approved applicator. Most roof systems require special application expertise to achieve lasting quality.
• Have the contractor explain his project supervision and quality-control procedures. Request the name of the person who will be in charge of your project, how many workers will be required and estimated completion time.
• Check to see if the contractor is a member of any regional or national industry associations, such as NRCA. Being a member of industry associations demonstrates a commitment to professionalism.
• Call your local Better Business Bureau or Department of Professional Regulation to check for possible complaints filed against the contractor.
• Carefully read and understand any roofing warranties offered, and watch for provisions that would void it.
• Choose a company committed to worker safety and education. Ask the contractor what type of safety training he provides for his workers and what industry education programs they have attended. The best roofing contractor is only as good as the workers who install the roof system.
• Keep a healthy skepticism about the lowest bid. If it sounds too good to be true, it probably is. Many fly-by-night contractors’ below-cost bids seem attractive, but these contractors often are uninsured and perform substandard work. Remember, price is only one of the criteria for selecting a roofing contractor. Professionalism, experience and quality workmanship also should weigh heavily in your decision.

Commonly asked questions
Q: How can a home owner recognize when a roof system has problems?
A: All too often, roof system problems are discovered after leaking or other serious damage occurs. Periodic (twice-a-year) inspections often can uncover cracked, warped or missing shingles; loose seams and deteriorated flashings; excessive surface granules accumulating in the gutters or downspouts; and other visible signs of roof system problems. Indoors, look for cracked paint, discolored plasterboard and peeling wallpaper as signs of damaged roof areas.
Q: What are my options if I decide to reroof?
A: You have two basic options: You can choose a complete replacement of the roof system, involving a tear-off of your existing roof system, or re-cover the existing roof system, involving only the installation of a new roof system. If you’ve already had one re-cover installed on your original roof system, check with a professional roofing contractor. In many instances, building code requirements allow no more than one roof system re-cover before a complete replacement is necessary.
Q: My roof leaks. Do I need to have it replaced completely?
A: Not necessarily. Leaks can result from flashings that have come loose or a section of the roof system being damaged. A complete roof system failure, however, generally is irreversible and a result of improper installation or choice of materials or the roof system installation is inappropriate for the home or building.
Q: Can I do the work myself?
A: Most work should not be done yourself. Professional roofing contractors are trained to safely and efficiently repair or replace roof systems. You can damage your roof system by using improper roofing techniques and severely injure yourself by falling off or through the roof.
Maintenance performed by home and building owners should be confined to inspecting roof systems during the fall and spring to check for cracked or curling shingles and cleaning gutters filled with dead leaves and other debris. If you must inspect your roof system yourself, use a firmly braced or tied-off ladder equipped with rubber safety feet. Wear rubber-soled shoes and stay on the ladder (and off the roof system), if possible.
Q: How long can I expect my roof system to last?
A: Most new roof systems are designed to provide useful service for about 20 years. Some roof system types, such as slate, clay tile and certain metal (e.g., copper) systems, can last longer.
Actual roof system life span is determined by a number of factors, including local climatic and environmental conditions, proper building and roof system design, material quality and suitability, proper application and adequate roof maintenance.
Roofing product manufacturers offer a variety of warranties on their products. Take a close look at those warranties to see what responsibilities and financial obligations manufacturers will assume if their products fail to reach their expected lives.
Q: What will a new roof system cost?
A: The price of a new roof system varies widely, depending on such things as the materials selected, contractor doing the work, home or building, location of the home or building, local labor rates and time of year. To get a good idea of price for your roof system, get three or four proposals from reputable contractors in your area. Keep in mind that price is only one factor, and it must be balanced with the quality of the materials and workmanship.
For each roofing material, there are different grades and corresponding prices. There also are a variety of styles and shapes. You need to look at the full product range and make a choice based on your budget and needs.
Within the roofing profession, there are different levels of expertise and craftsmanship. Insist on a contractor who is committed to quality work.
Q: How can I determine my annual roofing cost?
A: When considering your roofing options, the following formula may help:
Total Cost (Materials and Labor) ÷ Life Expectancy of Roof System (in years) = Annual Roofing Cost
Terms you should know
Deck/sheathing: The surface, usually plywood or oriented strand board (OSB), to which roofing materials are applied.
Dormer: A small structure projecting from a sloped roof, usually with a window.

Drip edge: An L-shaped strip (usually metal) installed along roof edges to allow water run off to drip clear of the deck, eaves and siding.
Eave: The horizontal lower edge of a sloped roof.

Fascia: A flat board, band or face located at a cornice’s outer edge.
Felt/underlayment: A sheet of asphalt-saturated material (often called tar paper) used as a secondary layer of protection for the roof deck.
Fire rating: System for classifying the fire resistances of various materials. Roofing materials are rated Class A, B or C, with Class A materials having the highest resistance to fire originating outside the structure.
Flashing: Pieces of metal used to prevent the seepage of water around any intersection or projection in a roof system, such as vent pipes, chimneys, valleys and joints at vertical walls.

Louvers: Slatted devices installed in a gable or soffit (the underside of eaves) to ventilate the space below a roof deck and equalize air temperature and moisture.

Oriented strand board (OSB): Roof deck panels (4 by 8 feet) made of narrow bits of wood, installed lengthwise and crosswise in layers, and held together with a resin glue. OSB often is used as a substitute for plywood sheets.
Penetrations: Vents, pipes, stacks, chimneys-anything that penetrates a roof deck.
Rafters: The supporting framing to which a roof deck is attached.

Rake: The inclined edge of a roof over a wall.

Ridge: The top edge of two intersecting sloping roof surfaces.
Sheathing: The boards or sheet materials that are fastened to rafters to cover a house or building.
Slope: Measured by rise in inches for each 12 inches of horizontal run: A roof with a 4-in-12 slope rises 4 inches for every foot of horizontal distance.

Square: The common measurement for roof area. One square is 100 square feet (10 by 10 feet).
Truss: Engineered components that supplement rafters in many newer homes and buildings. Trusses are designed for specific applications and cannot be cut or altered.
Valley: The angle formed at the intersection of two sloping roof surfaces.

Vapor retarder: A material designed to restrict the passage of water vapor through a roof system or wall.

A checkup on your roof system in the fall and spring will help diagnose potential problems early.
NRCA recommends you hire a professional roofing contractor to assist you with checking your roof. However, NRCA realizes many homeowners prefer to perform an initial inspection themselves. If you prefer to go that route, following are some important tips to get you started.
When cleaning your gutters or inspecting your roof system, remember important ladder safety tips:

• • Make sure the ladder is on solid, level ground.

• • Secure the ladder at the top to prevent it from slipping.

• • Inspect the ladder, rungs and rails for damage.

• • Extend the ladder at least 3 feet beyond the gutter, and angle it 1 foot back from the house for every 4 feet in eave height.

• Always use both hands when climbing the ladder.

Once on the ladder, you should look for:

• • Shingles that are buckling, curling or blistering; this indicates the end of the shingles’ life expectancy.

• • Loose material or wear around chimneys, pipes and other penetrations.

• Excessive amounts of shingle granules in your gutters; granules give shingles added weight and protect them from ultraviolet rays.

Before you hire a roofing contractor, do your homework:

• • Check for a contractor’s permanent place of business, telephone number and tax identification number.

• • Check references from prior customers.

• • Ask for proof of insurance (liability and workers’ compensation*).

• Ask the contractor about material and workmanship warranties.

Use the following form to record your roof system’s checkup each fall and spring.

If you diagnose a problem, hire a professional roofing contractor.