FAQ – Frequently Asked Questions

The following links, when selected, will provide information to frequently asked questions.

NOTE: Some of the information in this section is based on the technical bulletins published by the Asphalt Roofing Manufacturers Association (ARMA) and the Canadian Asphalt Shingles Manufacturers Association (CASMA).

FAQ’s About:

Selecting Shingles:

Installing Shingles

Asphalt Shingles Performance:

Shingles and the Environment:

Roof Types and Designs:

General Information

Question: What is the difference between fibreglass and organic shingles?

A: The difference between fibreglass and organic shingles is the type of mat that is used in production. Organic mats, which are used to make organic shingles, are composed primarily of cellulose fibres derived from selected recycled paper or converted wood chips. On the other hand, fibreglass mats which are used to make fibreglass shingles, are composed of glass filaments of various lengths and orientations, bonded together with inert binders. In most climates, both shingles, if installed properly on well-made roof decks, perform similarly.

Question: What are the most common asphalt shingles product and test standards?

A: The most commonly found product and test standards are:

ASTM E108: “Fire Tests of Roof Coverings” and ULC S-107: “Fire Tests of Roof Coverings” tests for roofs exposed to exterior fire hazards. Roof coverings are rated as Class A, B or C. Typically, glass shingle roof systems are Class A (including the underlayment), and organic shingle roof systems are Class C.
ASTM D225: “Asphalt Shingles (Organic Felt) Surfaced With Mineral Granules” is a product standard with requirements for organic shingles. All IKO organic shingles comply.
ASTM D3018: “Class A Asphalt Shingles Surfaced with Mineral Granules” is a product standard with some tests for Class A glass shingles.
ASTM D3161: “Wind Resistance of Asphalt Shingles” is a laboratory wind test.
ASTM D3462: “Asphalt Shingles Made from Glass Felt and Surfaced with Mineral Granules” is a product standard with requirements for glass shingles.
CSA A123.1-M: “Asphalt Shingles Surfaced with Mineral Granules” is a product standard with requirements for organic shingles.
CSA A123.5-M: “Asphalt Shingles Made with Glass Felt Saturated with Mineral Granules” is a product standard with requirements for glass shingles. All glass shingles comply (except Imperial Glass 20)

Note: Make sure that shingles purchased or used to meet the required standard.

See CASMA Technical Bulletin No. 5 (1993) for more information.

Question: Do asphalt shingles meet the Canadian building code?

A: All shingles, fibreglass and organic, meet the Canadian building code. Fibreglass shingles sold in Canada conform to CSA A123.5-98 product standards and organic shingles conform to CSA A123.1-98 product standards.

Question: Why / When should I use an asphalt shingle underlayment?

A: An asphalt shingle underlayment is typically dry felt that may be impregnated or coated with an asphalt saturant. The use of an underlayment is recommended for the following reasons:

Resins are produced by wood board decking. Asphalt-saturated felt protects shingles from the resins that may be released.
Asphalt-saturated felts protect decking material from wind-driven rain.
To validate warranties, many manufacturer’s require the use of asphalt-saturated felts on a wood deck.
The use of asphalt-saturated felt reduces “picture framing.” According to CASMA (1992), picture framing is the visible outline of deck panels caused by irregularities in roof decking thicknesses.
To obtain a Class A fire-resistance rating, asphalt-saturated felts should be used underneath shingles reinforced with glass fibre felt.
The underlayment should conform with CSA 123.3-M (No. 15 / ASTM D226 Type 1 No. 15 felt) and/or CAN 2-51.32 (Breather Type Sheathing Paper) industry standards.

See ARMA Form No. 219-RR-89 (1993) for more information.

Question: Can I apply new shingles over existing shingles?

A: Yes. You can apply new shingles over existing shingles, but it depends on the condition of the roof. If the roof has one layer of shingles that are lying flat and the deck is in good condition, the existing shingles typically do not have to be removed. Check with local officials to make sure that building codes are being followed. Re-roofing is a good opportunity to examine roof ventilation to ensure vents are sufficient in number, positioned properly and are unobstructed.

See CASMA Technical Bulletin No. 6 (1993) or ARMA Form No. 223-RR-96 (1996) for more information.

Question: What offsets should be used for laminated shingles?

A: For laminated shingles, the recommended offset is 25 cm. Typically, laminated shingles offsets range from fifteen to twenty-five centimetres. Regardless of the shingle type, it is always best to follow all application instructions printed on the shingle package. This will ensure proper roof performance and finished roof aesthetics. Laminated shingles must be applied with a minimum offset no less than 10 centimetres.

Question: How can I ensure proper performance from shingles in cold climates?

A: Proper performance from shingles installed and used in cold weather can be achieved by following the recommendations listed below:

Make sure that the roof is properly ventilated.
Be careful when using shingles in cold weather. They tend to get brittle and may crack or break. Try not to throw, drop or bend shingles.
If you are in an area that experiences freezing winter temperatures, eaves protection should be used to reduce water damage from ice dam formation. Use self-adhering eave protector membranes. They are easier to work with in cold weather.
Hand seal asphalt shingles in cold weather with an asphaltic cement recommended by the manufacturer.
When applying ridge caps, keep the shingles that are being used as ridge caps in a warm place so that they will be flexible enough to bend.
When recovering an existing roof with new shingles, make sure that the old shingles are flat.
In areas that receive high amounts of snowfall, try not to damage shingles when removing snow. Damage caused by snow removal is not covered under our limited material warranty.
Use caution if walking on a roof in the wintertime. The sealant bond between shingles can become quite brittle in cold weather. Therefore, traffic on the roof may cause sealant bonds to break.

See CASMA Technical Bulletin No. 8 (1996) for more information.

Question: Which type of fastener should be used to install asphalt roof shingles – nails or staples?

A: IKO agrees with and supports the ARMA position that nails are the preferred method of fastening asphalt shingles due to their superior holding strength. The following fastening tips apply to most IKO shingles; (check specific product application instructions for further information):

A minimum of four fasteners per shingle is used.
Correctly place and position fasteners below the sealant strip, but above the cutout on three-tab shingles, and in the nail line on laminated shingles.
The fasteners must be straight and flush with the surface of the shingle, not sunk into the shingle or sticking up at any point.
Make sure there is correct penetration of the deck as specified by ARMA and the NRCA.

See ARMA Form No. 221-RR-93 (1994) for more information.

Question: Do I need to peel the release tape off the shingles?

A: The plastic release film on the back of asphalt roof shingles does not need to be removed.

The sole purpose of this tape is to prevent the shingles from sticking together in the package. Once the shingles have been removed from the package and are applied in the correct orientation on the roof, the release tape serves no purpose whatsoever. The shingle sealant, which bonds the shingles together, is located elsewhere on the shingle and will seal succeeding courses of the shingles together on the roof when warmed by the heat of the sun, soon after application.

Question: What is causing the algae growth on my shingles?

A: Algae growth is typically seen on light-coloured shingles. It exists as a brown to black discolouration of the shingle and is caused by algae known as Gloeocapsa.

Although algae may exist on a shingle, it does not affect the performance of the shingle. Essentially, this is an aesthetic problem.

See CASMA Technical Bulletin No. 13 (1997) or ARMA Form No. 217-RR-89 (1997) for more information.

Question: How do I get rid of the algae growth on my shingles?

A: There are several ways to reduce discolouration:

For a new roof, install zinc or galvanized type metal near the ridge of the roof. As the metal ions are oxidized and erode off of the metal strip, they wash down the roof inhibiting cellular algae growth.
A dilute solution of chlorine bleach, trisodium phosphate and water can be applied – one part chlorine bleach to three parts water with a quarter cup of trisodium phosphate. Note: Trisodium phosphate should be available at any paint supply store. Gently spray the solution on the shingles. For stains that are hard to remove, scrub mildly. Scrubbing too harshly will remove granules. Rinse the shingles thoroughly with water. In the past, this has been a temporary solution and usually needs to be repeated every couple of years. Apply this solution carefully to avoid damaging other parts of the building or the shrubbery below.
Due to the increase in algae discoloured roofs, shingles are now available with small quantities of zinc or copper granules embedded in the mineral surfaced granule coating. These particles inhibit the algae growth through some of the life of the asphalt roof.

See CASMA Technical Bulletin No. 13 (1997) or ARMA Form No. 217-RR-89 (1997) for more information.

Question: Can bird excrement affect asphalt roofing products?

A: A build-up of bird excrement on asphalt roofing products can have negative effects if it remains on the product for a considerable amount of time. In some instances, it can even shorten the life of the product. There is a U.S. based company named Bird-X that offers several ways to reduce this problem. They can be contacted at 312-226-2473 or www.bird-x.com

Question: Are there any asphalt shingles specifically designed for hail conditions?

A: Yes, the premium designer shingle. It is a two-layer shingle, the top layer of which is composed of a dimensionally stable, heavyweight, nonwoven glass fibre mat which is thoroughly impregnated and coated with SBS modified asphalt. This special asphalt gives premium designer shingles superior tear and tensile strength characteristics. These shingles carry a UL 2218 Class 4 impact resistance rating.

Question: Should I be concerned about small bubbles/blisters on my shingles?

A: No. Practically all asphalt shingles have, by the nature of their manufacture, a greater or lesser degree of blistering potential under certain conditions or combinations of conditions. Generally, blistering is difficult to see from ground level and does not necessarily shorten the life of the shingle.

Question: What is colour, shading?

A: A roof observed from different lighting conditions or angles may have darker or lighter spots in certain areas. This apparent colour difference is referred to as “shading.” Shading is usually caused by unavoidable slight variations in texture which occur during the shingle manufacturing process.

Black or dark-coloured shingles are more prone to shading problems. A small amount of light is reflected from dark surfaces. Therefore, even slight textural differences may cause shading. Light-coloured shingles reflect greater amounts of light than darker shingles, and as a result, it is harder to notice shading problems. Since blends are made from several colours, shading differences are masked and are even less noticeable.

The material on the back of a shingle is sometimes transferred to other shingles that are next to it. Also, when shingles are stacked too high or stored for long periods of time, stains can develop. Both conditions can create the appearance of shading. These are only temporary problems, and they will naturally weather off. Note: Shading does not affect the water-shedding performance or life expectancy of a shingle.

See ARMA Form No. 201-RR-71 (1993) for more information.

Question: What can I do to reduce the potential for shading?

A: To reduce the potential for shading:

Do not mix shingles with different production codes on the same roof.
Make sure you follow the application instructions provided on the shingle wrapper.
Apply the shingles starting from the bottom of the roof and move across and up.
Use blended shingle colours instead of solid colours.
Do not stack shingles higher than what is recommended by the manufacturer.
Do not store shingles for long periods of time.

See CASMA Technical Bulletin No. 17 (1998) or ARMA Form No. 201-RR-71 (1993) for more information.

Question: My gutter is filled with granules. Is there a problem with my shingles?

A: Not necessarily. An excessive amount of granules are applied during the shingle manufacturing process to make sure that the asphalt on the roofing sheet is completely covered. It is important to completely cover the sheet with granules so that the asphalt is not exposed to ultraviolet light.

The granules are then pressed in. Due to the excessive amount of granules applied, some of the granules are only held loosely in place. Most of the excess granules are removed by the shingle manufacturing process, but some of these granules do get packaged with the shingles. These excess granules are known as “hitchhiker” granules.

“Hitchhiker” granules will typically come off during the first two years of shingle exposure on the roof. They usually will be found in gutters or at the bottom of the downspout. The loss of these granules is normal and does not affect the performance of the shingle. Granule loss only becomes a problem when the asphalt becomes exposed on the surface of the shingle.

See CASMA Technical Bulletin No. 18 (1999) for more information.

Question: What are the thermal properties – R-Value of plywood?

A: Thermal Conductivity

Its thermal conductivity, k measure the ability of a material to conduct heat. The higher the k value, the greater the ability of the material to conduct heat; the lower the k, the higher the insulation value. Thermal conductivity varies with timber species; however, an average value of k=0.1154 W.m/(m2 oC) for softwood timbers is sufficiently accurate for determining the overall coefficient of heat transmission (U value) of a construction assembly.

Thermal Resistance

The thermal resistance or insulating effectiveness of plywood panels based on k=0.1154 W.m/(m2 oC) is R=8.67 (m2 oC)/(W.m). The higher the R-value, the more effective the insulation.

For example, the R value for 12mm plywood = (12/1000) x 8.67 = 0.10 m2 oC/W. Similarly, the R value for 25mm thick pine plywood is (25/1000) x 8.67 = 0.22 m2 oC/W.

Question: Are asphalt shingles good for the environment?

A: Shingles are good for the environment because they protect your home/building from damage from the elements. They are durable, lightweight, contain recycled post-industrial materials, and are easily maintained. See the attached industry bulletin from the Canadian Asphalt Shingle Manufacturers Association which outlines other environmental benefits.

Question: What is a “green” product?

A: Although there is no consensus definition, a “green” product is generally considered to be one that has minimal impact on the environment. Green products are factors in designing for sustainable development.

Question: What is meant by sustainable development?

A: Sustainable development is a development that meets the needs of the present without compromising the ability of future generations to meet their own needs.

Question: How can I compare different shingle brands to see how green they are?

A: There are several environmental programs which give standards and limits for various aspects of shingles (i.e. recycled content, longevity, use of local raw materials, etc.).

Question: What are some of these programs?

A: At this time, some of the major ones are:

– ENERGY STAR™

– LEED™

– Built Green™

– NAHB

There are many others, including regional variations of the ones listed above. Each program asks questions and then “awards” credits or points so you can quantitatively compare different building practices and materials, including shingles.

Question: Which environmental program should I use?

A: The choice is completely up to you. Look at each program and determine which one suits your needs.

Question: What is ENERGY STAR™?

A: ENERGY STAR™ is a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy designed to encourage builders/homeowners to save money and protect the environment through energy-efficient products and practices.

Question: How does ENERGY STAR™ work for shingles?

A: The shingles must have a minimum solar reflectance (tested right out of the package and again after three years on the roof) and a comparable (with non approved shingles) warranty program. It is assumed that better shingle solar reflectance if used on every roof within an urban area, may reduce the overall temperature in cities (heat island effect), which in turn would lower the energy load needed for air conditioning. In terms of the practical benefit to the individual home directly, shingle colour is irrelevant to home heating and cooling costs since the attic floor is typically well-insulated and the attic is also ventilated.

Question: Are there any financial advantages for using ENERGY STAR™ approved shingles?

A: There may be some tax advantages with using ENERGY STAR™ approved shingles in some areas; check with your local government.

Question: What is Built Green™?

A: Built Green™ is an environmental building program, developed in partnership with various government agencies. Built Green is designed to help home buyers find a quality, affordable homes that offer opportunities to protect the health of their families and the environment. Currently Built Green™ is more popular in the west, but it is expanding across the country.

Question: How does Built Green™ work for shingles?

A: Built Green™ has a checklist of “Built Green™ approved” brands. Their criterion is primarily based on limited warranty period (the longer a product lasts the more points you get; 2 points for 25-year products, and 1 point for each additional 5 years up to a maximum of 4 points), recycled content (minimum 25% recycled content equals 3 points (the most a product can get), etc. IKO has several products on the “approved” list.

Question: What is LEED™?

A: LEED™ is an acronym for Leadership in Energy and Environmental Design. It is a program sponsored and administered by the U.S. Green Building Council (and by Canadian Green Building Council in Canada). LEED™’s purpose is to provide a rating system that encourages designers and builders to choose “green” building products for the construction and operation of buildings. While there are currently dozens of other environmental programs (such as Built Green, and Green Globes), LEED™ seems to be the major one at this time.

Question: How does LEED™ work?

A: When you have a LEED™ project, the design, location, materials, and how the project affects the surrounding area can earn you credits. If you obtain a certain number of credits, your project will be awarded a Platinum, Gold, or Silver, certification. It should be noted that neither manufacturers nor products can be “LEED™ certified”.

Question: How can our products help the designer earn LEED™ credits?

A: Our building product can help earn credits in the areas of insulation, reflective coatings, recycled material, and regional material.

Question: Which products can earn LEED™ credits?

A: All shingles have some recycled content. All saturated felts, modified bitumen membranes has some recycled content. Depending on the project location, our products could qualify for regional material credits.

Question: What Is NAHB?

A: NAHB is the National Association of Home Builders, and they are a Washington, D.C.-based trade association whose mission is to enhance the climate for housing and the building industry. Chief among NAHB’s goals is providing and expanding opportunities for all consumers to have safe, decent and affordable housing. As “the voice of America’s housing industry,” NAHB helps promote policies that will keep housing a national priority.

Question: Does NAHB have a “green “program?

A: Yes. Their program is called “NAHB National Green Building Program”. Points are primarily awarded based on a building material’s recycled content (no minimum level is given). In the roofing section specifically, one can earn a point simply by using an ice and water protector.

Question: How do I know a shingle product qualifies for an environmental program?

A: Ask the building designer what the requirements are, i.e. what environmental program they’re using, or what product characteristics they need to have. We have several products which will meet the requirements for recycled material, reflectivity, regionally produced material, etc.

Question: Can you give us a list of the number of credits for each product?

A: No. The requirements for each program keep changing, so it is best to contact Technical Support for the latest requirements and complaisance. LEED™, for example, is broken down into 9 Standards (e.g. New Construction, Homes, etc.) and each one has different requirements (see table below). So you must first determine what the criteria are and then contact Technical Support. They will provide you with the latest data.

LEED™ points by LEED™ Standard

Note:

* 1 point if recycled content (post consumer plus ½ post industrial) is =10%.

2 points if recycled content (post-consumer plus ½ post industrial) is =20%.

** 0.5 points if recycled content (post consumer plus ½ post industrial) is =25%.

Question: Can I get credits for using reflective shingles on my home?

A: There are no LEED™ points (credits) for highly reflective shingles. But you can get ENERGY STAR™ credit for using an ENERGY STAR™ approved shingle.

Question: Are my old shingles recyclable?

A: Many local government agencies and private companies have started recycling programs for used shingles. The shingles can be recycled into road paving material and other materials. Check with your local government. It is important to note that the old shingles may need to be “clean”; i.e. free of any nails, wood or other foreign material which can often end up as included in roof tear-off material.

Question: What is Green-washing?

A: Green-washing is a term used to describe the perception of consumers that a company is misleading them regarding the environmental practices of the company or the environmental benefits of a product or service. It is a deceptive use of green PR or green marketing. The term green sheen has similarly been used to describe organizations which attempt to appear that they are adopting practices beneficial to the environment.

“Six Sins of Green-washing”

In December 2007, environmental marketing company TerraChoice gained national press coverage for releasing a study called “The Six Sins of Green-washing,” which found that 99% of 1,018 common consumer products randomly surveyed for the study were guilty of green-washing. According to the study, the six sins of green-washing are:

The sin of the Hidden Trade-Off: e.g. “Energy-efficient” electronics that contain hazardous materials. 998 products and 57% of all environmental claims committed this Sin.
The sin of No Proof: e.g. Shampoos claiming to be “certified organic,” but with no verifiable certification. 454 products and 26% of environmental claims committed this Sin. It should be noted that IKO’s recycled content claims have been independently verified.
The sin of Vagueness: e.g. Products claiming to be 100% natural when many naturally occurring substances are hazardous, like arsenic and formaldehyde (see an appeal to nature). Seen in 196 products or 11% of environmental claims.
The sin of Irrelevance: e.g. Products claiming to be CFC-free, even though CFCs were banned 20 years ago. This Sin was seen in 78 products and 4% of environmental claims.
The sin of Fibbing: e.g. Products falsely claiming to be certified by an internationally recognized environmental standard like EcoLogo, Energy Star or Green Seal. Found in 10 products or less than 1% of environmental claims.
The Sin of Lesser of Two Evils: e.g. Organic cigarettes or “environmentally friendly” pesticides, This occurred in 17 products or 1% of environmental claims.

Question: What is a drip edge, and how is it applied?

A: Drip edges are used for water-shedding at the eaves and rakes and for preventing wood materials from rotting. It is important that the drip edge is “made of a corrosive-resistant material that extends approximately 120mm back from the roof edges and bends downward over them.” (Residential Asphalt Roofing Manual, 1997)

The drip edge should be applied beneath the underlayment or eave protection along the eaves and over the underlayment on the rakes.

Question: What are low slope roofs?

A: Roofs that have slopes of 18.4 degrees or less are considered to be low slope roofs. Never apply asphalt shingles to slopes that are below 8.5 degrees. Shingles applied on low slope slopes do not last as long as shingles on steeper roof pitches, due to the increased exposure to sunlight and other weather conditions. Generally, laminated/architectural shingles are better suited to steep roofs and do not offer aesthetic benefits when applied on low slopes.

Question: How can I reduce some of the problems associated with low slope roofs?

A: Low slope roofs are more susceptible to water entry due to ice dams and wind-driven rain. Therefore, the key to a successful low slope roof is to increase the water-shedding properties of the roof system.

Rain and melting snow do not run off quickly on low slope roofs. As a result, the potential for ice dams is increased. By providing adequate ventilation, the formation of ice dams can be decreased. Note: “The National Building Code of Canada allows various types of ice dam membranes to be used, but CASMA recommends that self-adhering modified asphalt membranes be used.” (CASMA Technical Bulletin No. 16, 1998)

Wind-driven rain is another concern associated with low slope roofs. By improving the underlayment or by using a special shingle application method, the damaged caused by wind-driven rain can be reduced.

See CASMA Technical Bulletin No. 16 (1998) for more information.

Question: I want to shingle my roof. How many shingles will I need?

A: By using simple calculations, you can estimate the number of shingles that will be needed to complete the job. Roofs come in many shapes and sizes and can be classified into simple geometric shapes such as squares, rectangles, trapezoids and triangles. To determine how many shingles will be needed, you must calculate the area of the roof. This is done by figuring out what geometric shapes make up your roof, calculating the area of the individual shapes and summing the areas to give you the total area of the roof. The area required is then divided by the area each bundle covers. Don’t forget to add allowances for ridges, starter strips, etc.

Question: What will happen if my roof is not properly ventilated?

A: Insufficient ventilation can lead to:

Asphalt odours from hot shingles entering the home’s interior.
Blistering, fish-mouthing, curling or premature aging of asphalt shingles.
Rotting of wood decks.
Buckling.
Splitting.

Proper ventilation is essential so that air movement is not restricted beneath the roof surface.

See CASMA Technical Bulletin No. 1 (1992) or ARMA Form No. 209-RR-86 (1994) for more information.

Q: How much ventilation do I need on my roof?

A: The amount of ventilation needed is determined by the size and design of the roof. For roof and attic spaces above an insulated ceiling, the vent ratio is one square metre of net free ventilating area/300 square metres. For low slope roofs or roofs with cathedral ceilings, the vent ratio is one square metre/150 square metres.

See CASMA Technical Bulletin No. 1 (1992) or ARMA Form No. 209-RR-86 (1994) for more information.

Question: Are asphalt shingles OK for catching drinking water?

A: There have been tests conducted that show no measurable toxins in the water samples collected off asphalt shingle roofs.

Having said that it is advisable to filter all drinking water that you are collecting off a tin roof, tiled roof or asphalt shingle roof as you are filtering impurities that come from animal excrement on the roof and in gutters, toxins from the atmosphere etc…

Question: Are our roofing products required to have Material Safety Data Sheets (MSDS)?

A: The following roofing products do not require MSDS’s, as they are either considered manufactured articles or are made predominantly of wood:

– Wood Fiber Insulation Board Products – Organic Based Roofing (Shingles, Rolls, Felts)

– Fiberglass Based Roofing (Shingles, Rolls, Felts) – Roofing Asphalt

– APP and SBS Modified Bitumen Roofing – ArmourGard Ice and Water Protector

– Adhesive backed rubberised membrane Vapour Retarder – Protectoboard

Question: If I have a shingle concern, what should I do?

A: If you have a shingle concern (e.g. splice, severe granule loss, etc.), please contact the customer service department in your area (U.S. 1-800-433-2811; Eastern Canada 1-800-361-5836; Western Canada 1-800-521-8484). You will be required to submit a copy of the proof of purchase.

Question: Can I paint my roof?

A: Yes. The effect of paint on shingles if very negligible. Technically, it could be argued that the paint will help the shingles weather longer. Some roof coatings that are advertising to extend product life are simply premium quality latex paints.

Question: Do I have to use a certain type of paint on my roof?

A: Yes. Latex paints must be used. Latex paints will do nothing more than colour the shingles. On the other hand, oil-based paints may soften the shingles slightly due to the solvents that they contain. These solvents will evaporate quickly, so if used carefully, there should not be any lasting effects. Generally regardless of paint used, paint weathers off of the shingles within five years. How long the paint lasts depends on the quality of the paint, the pitch of the roof, climate etc.…

Question: How are shingles made?

A: Shingles are made in a continuous web process. Large rolls of felt are fed into a dry looper, which serves as an accumulator. The felt then goes to the saturator tank. In the saturator tank, the felt is impregnated with saturant asphalt. From the saturator tank, the felt moves to the wet looper, where the saturant is drawn into the felt as it cools. This allows the felt to attain a high degree of saturation and dries the surface of the sheet. The saturated organic felt, or the glass mat (glass mat shingles do not require the saturation process) moves to the coater. At the coater, coating (asphalt with air blown through it) is applied to the top and bottom surfaces of the sheet. Mineral stabilizers are added to the coating, which improves the shingle’s fire resistance and weather ability. Next, granules are applied to the top surface of the coating. Granules are ceramically coloured crushed rock; the granules give the shingle its colour but more importantly protect the coating from ultraviolet light. Back-surfacing is then applied to the sheet to prevent it from sticking to the machine and other shingles when packaged. The release tape is also applied to the back of the sheet to prevent the sealant buttons from sticking to the next shingle in the package. The granules are then pressed into the top coating. Once the sheet is cooled, sealant buttons are applied. The sealant buttons allow one shingle to bond to the overlying shingle on a roof, to prevent wind uplift. The roofing sheet is then measured and cut into shingles. At this stage, the two pieces of laminated shingles have adhered together. The shingles are wrapped into bundles and stored in the warehouse until they are ready to be shipped to the appropriate location.

Question: What are ice dams?

A: Ice dam formation is the result of continuous freezing and thawing of snow due to escaping heat from the house or gutters being backed up with frozen slush. When this occurs, water may be driven under the roof, which may cause ceiling, wall, insulation and gutter damage.

See CASMA Technical Bulletin No. 10 (1996) or ARMA Form No. 215-RR-87 (1993) for more information.

Question: What can I do about ice dams?

A: Ice dams can be prevented from forming by:

Installing a vapour barrier above the home’s warm space.
Insulating the attic floor.
Ventilating the attic.

Damage from ice dams, if they do form, can be reduced by:

Removing debris from gutters so that it does not build up over time.
Making sure that the outer edges of the gutters are lower than the slope line. This will allow for snow and ice to slide clear.
Installing eaves flashing, such as Ice & Water Protector

See CASMA Technical Bulletin No. 10 (1996) or ARMA Form No. 215-RR-87 (1993) for more information.

Question: Can I use salt to remove the ice on my shingles?

A: Yes, but there are some drawbacks to doing this.

See CASMA Technical Bulletin No. 15 (1998) for more information.

Question: Can I use a shovel to remove snow and ice from my shingles?

A: Yes, but it is not recommended.