What is Roof Flashing?

What is flashing?

Flashing is a construction detail used to seal and protects joints in a building from water penetration. The joints created by the intersection of the roof and roof mounted structures and projections, such as parapets, hatches, skylights, chimneys, vent stacks, or towers, are among the most vulnerable areas of roofing systems. They constantly expand and contract in response to changes in humidity and temperature. Greater the number of such projections, greater the potential for leaks.

Roof flashing represents a very simple and intuitive engineering technique that has been known for hundreds of years. The whole idea depends almost entirely on gravity. If the flashing has been installed correctly, gravity will work with the flashing material to shed the water onto the regular roofing materials, where it is then directed harmlessly to the ground. Roof flashing is commonly used around chimneys, fan vents, plumbing vent stacks, and other items that project out of residential roofs.

Roofers Lingo

Algae Discoloration: A type of roof discoloration caused by algae, also called fungus growth.

Blisters: Bubbles that may appear on the surface of asphalt roofing after installation.

Asphalt Shingle: a shingle manufactured by coating a reinforcing material (felt or fibrous glass mat) with asphalt and having mineral granules on the side exposed to the weather.

Caulk: To fill a joint in order to prevent leaks.

Counter Flashing: That portion of the flashing attached to a vertical surface to prevent water from migrating behind the base flashing.

Deck or Decking: The structural “skin” of a roof over which roofing in applied. Most new homes have decking made of plywood.

Flashing: Pieces of metal or roll roofing used to prevent seepage of water into a building around any intersection or projection in a roof such as vent pipes, chimneys, adjoining walls, dormers and valleys.

Gable Roof: A type of roof containing sloping planes of the same pitch on each side of the ridge. A gable roof typically contains a gable at each end.

Granules: Ceramic-coated colored crushed rock that is applied to the exposed surface of asphalt roofing products.

Gutter: The trough that channels water from the eaves to the downspouts.

Overhang: That portion of the roof structure that extends beyond the exterior walls of a building.

Parapet: A low protective wall that extends above the roofline or balcony for support.

Best Solution for Roof Repairing!

ThermaCote acrylic roof coatings are best alternatives for repairing roof leaks on metal roofing. They are eco-friendly and also available in liquid format. These roofing materials designed to permanently repair persistent roof problems such as roof breaks.

Energy-efficient acrylic energy saving coatings is in popular among marketers as well among the customers. Rising electricity bills and the effects of urban heat landmasses have made white, reflective roof systems the product of choice for most roof maintenance applications. Using energy-efficient roofing materials results in cooler roof surfaces and less energy spent for air conditioning.

White, water based acrylic roof coatings provide the highest reflectivity and the best longevity at the most economical price.

What are roof coatings?

A roof coating is a monolithic, fully adhered, fluid applied roofing membrane. It has elastic properties that allows it to stretch and return to their original shape without damage.

Typical roof coating dry film thickness vary from paint film thickness to more than 40 dry mils. This means a roof coating actually becomes the top layer of a composite roof membrane and underlying system. As such, the roof coating is the topmost layer of protection for the membrane, receiving the impact of sunlight (both infrared and ultraviolet (UV), rain, hail and physical damage.

Benefits

Roof coatings are seamless and when installed correctly, can solve roof leaks on almost any type of roof substrate.

There are exceptions: "professionals do not recommend using cool coatings over existing shingles. This technique can cause moisture problems and water damage because the coating can inhibit normal shingle drying after rain or dew accumulation, allowing water to condense and collect under the shingles." 

Field-applied reflective roof coatings can extend the useful life of nearly every roof substrate keeping a roof surface cool and providing a level of protection from the sun and weather.

However, coating asphalt shingles and built-up composition roofs requires more caution. The National Roofing Contractors Association’s director of technical services has stated "The roofing industry is aware of a number of issues that could have negative consequences for field application of coatings over asphalt shingle roof systems. Anyone considering this type of application should be aware of the concerns so they can weigh them against the benefits claimed in coating product promotional materials." 

Roof coatings can add 25 years to the service life of a roof and reduce the amount of discarded roofing materials that end up in landfills. The infrared image on the right shows "175°F" on the uncoated (black) section of the modified bitumen roof. The coated (white) section is "79°F". Field studies have shown that cool roof coatings can lower rooftop temperatures and reduce air conditioning bills.

How to Properly Clean Your Roof

1. Pressure Wash the Roof - Pressure washing is the most common technique for cleaning the roof, as it is effective and can combine with detergent to improve cleaning efficacy. It is important to note that you must be careful not to damage joints, penetrations and side and end laps when cleaning with a pressure washer.
2. Clean the Roof with a Heavy Bristle Broom - If you don't have a pressure washer accessible, you can use a heavy bristle broom and water hose to clean the roof.
3. Clean All Remains Off the Roof - After the roof is sufficiently cleaned, it must be thoroughly rinsed and all debris flushed down the drains or into the sewers.

How to Test the Roof for Adequate Coating Bond:

1. Apply 2" masking tape to an area of the roof that had previously been dirty, such as a ponded water section or a drain sump. Press the tape firmly into the roofing substrate.
2. Peel the tape back:
• If it is difficult to peel off and there is no dirt or degraded roofing material on the backside of the tape, proceed with coating.
• If it peels easily with dirt or degraded roofing material embedded on the bottom of the tape, you should clean again and retest.

The Necessity of Cool Coatings for Concrete

A discovery fundamental to the building construction issue is concrete. It is an ancient Roman creation that was a revolution to construction which when reinforced with steel enabled towers and expressways to come into being. Did you know that concrete stores hotness from the sun and it heats up our air significantly due to its universal use? Did you know that it deteriorates slowly to probable failure at some point in its life span? Unless it is coated, it will eventually fail and need reparation or replacement due to water deterioration to the strengthening rebar. As it is now, due to the scale and widespread nature of its use, concrete is a major contributor to the “Urban Heat Island Effect” since unpainted concrete acts as a thermal heat sink in all sun exposed locations and “re-radiates” the thermally accumulated sun’s radiation into the atmosphere after the sun goes down. The overheated air in cities and suburbs catalyzes more air pollution by chemical reactions which occur as the atmospheric temperatures increase. Massive carbon pollution further occurs from generation of the electricity at fuel-burning utility plants supplying the energy to run air conditioners inside millions of such buildings into the night.

Roof Coatings Protect Roofs from UV Rays!

While there are several reasons why a roof can start leaking, many people do not realize that the UV rays from the sun are the most damaging to your roofs surface. Dark roofs absorb a great amount of the sun’s heat- UV rays, causing the roof to become a brittle, less elastic substrate. When your roof becomes brittle, the membrane may lose thickness and become less defensive against leaks. A similar situation occurs when the roof loses the capability to expand and contract with fluctuating temperatures - cracks occur and seams split, leading to roof failure and more leaks. It is important to use one of the AcrylicRoof Coatings to protect your roof against these common side effects from the sun.

How Do I Know if the Roof Coating Coverage is Correct?

This is an important question because many roofing provisions and warranty policies require a specific number of dry coat thicknesses to be applied on the structure. To ensure your roofcoating exposure is correct, you will need a wet mil gauge and the volume solids of the roof coating you are using.

What do you mean by wet mil gauge? A wet mil gauge is a tool that is used to define the thickness of the wet coating after it has been applied to the roof surface. It is simply a gauge with points that is pressed into the elastomeric roof varnishes immediately after it has been applied on the roof. The device is then withdrawn vertically with coating stuck to some of the points. You want to note the deepest points having coating on it and the next deepest points that do not have coating on it. The true wet film thickness is somewhere between the two readings. Once you have determined your wet mil thickness, you then need to know the percent solids by volume in the coating. The wet film thickness is then multiplied by the percent of volume items to give you your dry film width.

Although it is a relatively simple procedure to figure out the actual dry film wideness of your roofing structure, there are three important factors to consider having the proper roof coating coverage for your building or house. First, is the measurement of the wet film thickness immediately after the application of the roof varnishes to ensure the coating does not evaporate or dry, as this would give you wrong measurements. Second, is the wind loss factor when applying roof coatings. A 20 mph winds may result into a loss of 20- 30% of the coating essential. Last, is the need for extra material that could be from 3- 10% of the overall amount of coating required for the structure to account for thickness variations in the applications as well as for the miscellaneous coating remains in the lines and in the vessels.

Achieving the proper roof coating coverage is a very significant step in applying a roof coating process to any building. 

Long lasting Paints for Roofs!

In Australia, there was a huge demand for long-lasting, effectual, cool coatings for metal and tile roofs that could be economically field-applied to houses in the vast Australian continent. We chose acrylic energy saving coatings which are bit expensive but are really very effective. This coating is also comes in liquid format which is very useful while application. A benefit of this coating is that they add 12 to 15-year lifespans to your roof which is cost-savings benefits with twice the lifespan of standard paints. They cooled the buildings dramatically by reflecting away the majority of the sun’s radiation and by releasing a very high percentage of the heat that did find its way into the underlying substrate materials. This is called thermal emissivity.

Other benefits were that these reflective paints required no special processes to apply, while being largely more environmentally friendly and lower in odour. This coating is IR reflective, low toxic in nature, with low Volatile Organic Compounds unlike the liquid, organic-based standard paint tint systems. 

Acrylic Roof Membrane Saves Energy Costs!

Did you know that a dark coloured roof absorbs so much heat that flows not only into the space below it but also back into the atmosphere thereby causing an urban warming or heat island effect. On the other hand, a white rooftop replicates sun’s rays and thereby absorbs much less heat, requires less energy from air conditioning.

Lowered Air Conditioning and Cooling Costs

Acrylic coatings can save as much as 20% or more in energy costs. A reflective roof membrane has the ability to replicate the sun’s UV and infrared rays, allowing the roof temperature to increase only by 12 F. With a lower temperature rise of the cooler roof is a reduced heat transferred to the insides of the building. This relates to a significant decrease in electrical energy demand for air conditioning. After the Acrylic Coatings was applied we definitely noticed a variance in house temperature. It's not a large difference but it is between 15-20 degrees cooler inside the storeroom and rooms. 

Restore your roof for longer period!

Roof painting is a process that restores your roof from extreme temperatures. We should apply roof coating or painting early enough to prevent from structural damage.  The process removes moss and lichen from your tiles and clean drainage by using power washing techniques, which are common in cleaning the pavements on busy High Streets.

The high pressure flow efficiently removes any moss and lichens built up without damaging the tiles.  We will also clean up sewers to make sure the finished job looks as decent as new. 

Cracked tiles and loose filling are replaced to make sure that all tiles, including the important ridge, stylish and bonnet tiles protected are in good condition and are waterproof.  We can then think about applying the protective coating applied to roof. This coating is high performance thermal barrier that uses ceramic technology to prevent the transfer of heat or cold, which comes in a liquid sealant form endowing it with a host of additional useful properties. This coating is easily applied to a number of different surfaces. This roof coating is a breathable Vapour Barrier, as well as an Air and Water Barrier. They helps seal the envelope of any structure making existing insulation in any home or business perform closer to its R-value. This roof painting allows entrapped moisture to escape or be released without damage to the coating or substrate surfaces.

High Performance Roof Coatings

A high performance reflective roof coating has high quality UV blocking materials in order to protect your roof from the leading causes of roof degradation - sun damage from UV and Infrared rays. Not only does the high reflectivity lower air temperature inside the building but also by replicating a majority of the harmful UV heats away from the exterior of the roof, the roof is protected from cracking, splitting, weathering and ultimately from leaking. ThermaCote Coatings has several highly reflective roof coatings that can be applied over almost any roofing surface. Click here to learn more about the ThermaCote product line, which was engineered to lower the energy costs, and produce green energy coating : http://thermacote.com/