Why is flashing important for a roof?
Flashing secures joints in your roof and places that tend to receive a lot of water, like valleys between slopes. With adequate flashing, water is directed away from vulnerable areas of the roof and into gutters. Without flashing a roof would almost certainly develop leaks in sensitive areas. The importance of roof flashing cannot be overstated.
What is roof flashing and why do you need it?
The primary purpose of flashing is protect a building during harsh water by keeping water from seeping beneath the shingles. Flashing works to reinforce weaker sections of the roofing system.
What is roof flashing, and what does it do?
Roof flashing is a thin piece of sheet metal, typically made from galvanized steel or other metals, which is used along with underlayment to direct water runoff away from susceptible areas like chimneys, vents, skylights, roof valleys, eaves, or where the wall and roof meet.
What materials are used in roof flashing?
Roof flashing is made out of thin metal strips used by roofers to protect all areas on your roof from water damage. The metal is usually aluminum, steel, and copper and is used in areas such as skylights, chimneys, vents, roof valleys, and areas where the roof meets the wall. Roof flashing generally lasts longer than your roof, which is why it ...
What is the main purpose of flashing?
Flashing is a sheet of thin, impervious material used to prevent water penetration or seepage into a building and to direct the flow of moisture in walls.
Where is flashing needed on a roof?
Flashing is critical to certain areas of your roof — namely, the places where the roof surface meets a wall (sidewalls and front walls), the low points where two roof slopes meet (called valleys), roof protrusions (bathroom/kitchen vents, skylights) and the roof's edges (rakes and eaves).
What does the term flashing mean in construction?
Flashing refers to thin pieces of impervious material installed to prevent the passage of water into a structure from a joint or as part of a weather resistant barrier system.
What are two types of flashing?
There are two general types of flashing used in masonry construction. The first is external flashing (exposed flashing) and the second is internal flashing (concealed flashing). External or exposed flashings prevent moisture from penetrating into masonry walls where the wall intersects the roof.
When should you install flashing?
0:073:34How to Install Flashing on a Roof | Mastering the Roof by GAF - YouTubeYouTubeStart of suggested clipEnd of suggested clipWhen the roof claims. But against vertical walls or chimneys metal flashing must be placed over theMoreWhen the roof claims. But against vertical walls or chimneys metal flashing must be placed over the end of each course. This procedure is called step flashing in this situation step flashing performs.
What are the different types of flashing?
Some types of roof flashing are counter flashing, chimney flashing, step flashing, headwall flashing (also called apron flashing), valley flashing, and gutter apron flashing.
What is the most common material used for roof flashing?
These common types of metals are aluminum, steel, or copper. The most common type of metal used for roof flashing today is steel. It gives you a clean look that fits most budgets.
What is flashing on siding?
What Is Flashing? Flashing is a material which goes between certain parts of your home to keep water from getting in. Most commonly found in roofing and siding, flashing is a supplement to your home's resistance to the elements.
What is a cover flashing?
counterflashing, cover flashing, cap flashing A strip of sheet metal, often built into masonry and turned down over other flashing; used to prevent water from entering the joints and the exposed upturned edges of base flashing on a roof.
Does flashing go over or under shingles?
Flashing should overlap the roof-covering material, but on asphalt shingle roofs, for aesthetic reasons, the part of the headwall flashing that extends down over asphalt shingles is often covered with a course of shingle tabs.
What material is used for flashings?
What materials are used for flashing? Flashing can be made from many different materials, including metal (copper, aluminum, stainless steel, lead, etc.), plastic, or composite materials. The most durable (and, therefore, most expensive) flashing material is metal sheet flashing.
What type of flashing is best?
Aluminum: While some materials are stronger and others cost less, aluminum remains the most popular choice of flashing among most homeowners. Aluminum makes a good balance for flashing material if you are on a budget but still want quality.
Does flashing go over or under shingles?
Flashing should overlap the roof-covering material, but on asphalt shingle roofs, for aesthetic reasons, the part of the headwall flashing that extends down over asphalt shingles is often covered with a course of shingle tabs.
Do you need flashing in roof valleys?
Closed valleys aren't required to have metal flashing, but they should have additional underlayment lining the valley, preferably a couple layers of roll roofing. You can usually see whether this has been done by looking carefully at the bottom edge of the valley.
How do you install flashing on the side of a house?
2:525:04How to Install Drip Edge and Step Flashing | This Old House - YouTubeYouTubeStart of suggested clipEnd of suggested clipMake sure the nail is down tight and flat. Okay the next thing i need to do is add another piece ofMoreMake sure the nail is down tight and flat. Okay the next thing i need to do is add another piece of flashing right here on top of the courses. As we go and that's called step flashing.
Can you add flashing to an existing roof?
Flashing is generally installed at any joints or edges in the roof where water could otherwise work its way in. In order to properly install new flashing, you'll have to remove the shingles surrounding your old flashing, and then re-lay them after installation.
What is Roof Flashing?
Take a nice hard, long look at your roof. Roof flashing is a thin material made out of metal that directs water away from certain spots on your roof, such as the walls, chimneys, and roof valleys.
Materials that go into making Roof Flashing
Now that you know what roof flashing is, you should know what they’re made out of. A variety of materials go into making Roof Flashing. These include copper, aluminium, galvanized steel, lead, and stainless steel. Flashing is also available in Zinc alloy metal.
What does Roof Flashing Do?
Roof flashing is crucial to ensure that the water doesn’t get under your shingles. The parts of the exterior wall and roofs prone to corrosion and water leakage could do with roof flashing. Flashing simply collects the rainwater and redirects it to some other location, say, the drainage.
Types of Roof Flashing
Base Flashing: Roofing components that require two pieces of flashing are ideal for Base Flashing. The major advantage of base flashing is that they are easy to install. The water is guided away from the roof. Base flashing moves along with the two pieces of flashing, and with weather changes, the roofing material expands and contracts.
Does Roof Flashing Ever Need Replacement?
If you are thinking about replacing a roof, you may be wondering if your roof flashing needs to be replaced as well. The answer is, maybe!
Why Should You Check Your Roof Flashing Regularly?
When you carry out your regular roof maintenance and inspection, ensure to check up on your roof flashing as well. This could be super helpful to prevent a roof flashing problem even before it ever happens.
Conclusion
The concept of roof flashing is simple. It is a thin metal layer made out of different materials (galvanized steel, aluminium, and copper are the predominant ones used) to redirect water away from the roof and prevent damage to your home.
What is roof flashing?
Roof flashing is a thin material, usually galvanized steel, that professional roofers use to direct water away from critical areas of the roof. Use roof flashing wherever the roof plane meets a vertical surface like a wall or a dormer. Additionally, install flashing to surround roof features, such as vents, chimneys, and skylights.
Do skylights need to be flashed?
Skylights: Often skylights have a built-in flashing to protect water from seeping in, but sometimes roofing professionals must create it or purchase it separately. First fit continuous flashing along the base of the window, then step flashing up the sides, and last saddle flashing would be installed at the top of the window.
What type of flashing is used on a roof?
There are 4 main types of flashing used in residential roofing systems: Valley flashing: This flashing is used in open valleys of the roof. Most often leaks are found in the valley flashings due to flashing that is nailed too tightly to the decking or shingles that are not trimmed far enough off the flashing.
When is step flashing used?
Step flashing: When a chimney or dormer wall intercepts the slope of the roof, step flashing is used. Step flashing is usually a metal piece that is bent in the middle, so that one end lays on the roof, and the other against the vertical wall of the dormer or chimney.
What is a course on a roof?
Course: A row of shingles or roll roofing running the length of the roof. Cricket: A peaked saddle construction at the back of a chimney to prevent accumulation of snow and ice and to deflect water around the chimney. Cutout: The open portions of a strip shingle between the tabs.
What is step sheathing?
Step sheathing: Step sheathing is used alone or in combinations with solid sheathing for installation of tiles or shakes. Step sheathing allows air circulations under the tiles by using 1-by-6 or 2-by-6 boards that are evenly spaced so that air can move under the tiles or shakes.
What is a downspout?
Downspout: A pipe for draining water from roof gutters. A downspout is also called a leader. Drip Edge: An L-shaped, non-corrosive, non-staining material (usually metal) used along the eaves and rakes to allow water run-off to drip clear of underlying construction. Eave: The horizontal, lower edge of a sloped roof.
What is the pitch of a roof?
For example, if a roof is “4 in 12″, the roof rises 4 inches for every horizontal run of 12 inches. The pitch of the roof is a big factor in determining the kinds of materials that can be used and the longevity of the roof.
Can ice dams cause roof leaks?
This, of course, can cause serious roof leaks– even in freezing temperatures. The best prevention to ice dams is a well-ventilated (cool) roof. Additional protection for your roof can be applied with an impermeable ice and water membrane. The membrane is installed on top of the decking, under the roofing material.
What is sheathing in roofing?
Sheathing. In the roofing industry, sheathing is of the utmost importance for insulation purposes. These 1 by 6-inch or 1 by 12-inch boards of plywood are nailed right into the rafters. Everything else, from shingles to other roofing materials, goes into the sheathing.
What is underlayment in roofing?
In the roofing business, the underlayment is the material that goes between the sheathing and the shingles. Usually, contractors gravitate toward using felt as their underlayment — which we’ve already talked about.
What is drip on a roof?
Drip. The drip is a metal edge along the eaves or the rakes that protects the fascia board from water damage. When it rains, the water will slide along the metal drip into the gutters instead of coming into contact with the wooden part of the roof.
What is the strip of sheet metal that runs underneath the roof tiles where different planes of the roof meet?
Flashing. Similarly to counterflashing, flashing is the strip of sheet metal that runs underneath the roof tiles where different planes of the roof meet. Like counterflashing, flashing is meant to prevent water leaks.
What is built up roofing?
Built-up roofing is a term for layering roofing felt and hot-mapped asphalt on a flat or low-slope roof. After laying down the felt and the asphalt, we’d top off the whole thing with gravel.
Where is drip metal on a roof?
Speaking of the drip, that piece of metal is actually attached to the lower edge of the roof — or the eaves. The eaves are the part of the roof that continues past the walls of the house.
Where is the cornice on a roof?
In roofing, this term signifies the part of the roof that sticks out from the sidewalls of a house.
What is the horizontal underside of a roof overhang?
Soffit. A soffit is the horizontal underside of a roof overhang, an archway, a staircase, a ceiling, or a similar architectural component. A little more trivia: From the Italian “soffitta” for under and “figgere,” to fix, the word “soffit” dates back to the days of early Palladian architecture.
What is the ratio of a roof's rise to each foot of run?
Roof slope is expressed as the ratio of a roof’s rise (vertical distance) to each foot of run (horizontal distance). A “4-in-12 pitch” means the roof rises 4 inches for every 12 inches of horizontal distance. The word “pitch” was first used in the early 17th century to denote “the highest point.”.
What is the thicker end of a shingle?
Here is a closer look at common roofing terms: The exposed end of a shingle. With wood shingles or shakes, this is the thicker end. The butt of a shingle is the end that faces ...
Where is the ridge board on a roof?
The ridge is the peak where two sloped roof sections meet. Part of a roof’s frame, a ridge board runs horizontally along the peak of a sloped roof. Essentially the spine of a conventional stick-framed roof, the ridge board is sandwiched between the meeting ends of the roof rafters.
How many inches does a roof slope?
A roof’s slope is the number of inches it rises for every 12 inches of horizontal “run.”. A roof with a “4-in-12 slope” rises 4 inches for every 12 inches of horizontal run. The same roof has a 4/12—or 1/3—pitch. The terms “pitch” and “slope” are simply two different ways of expressing the same measurement.
What is ASTM flashing?
ASTM – American Society for testing of Materials. A voluntary organization concerned with the development of standards, testing procedures, and specifications. Many city building codes use ASTM standards. Base Flashing – the portion of the flashing which is attached to, or rest on the roof deck.
What is bridging roofing?
Bridging – a method of reroofing where the new shingles follow the contour of the old roofing. Also called “butting up”. It is almost always desirable to tear off old roofing. Built-Up Roofing – a flat or low sloped roof made up of layers of asphalt and ply sheets.
What is laminated shingles?
Laminated Shingles – shingles containing more than one layer of tabs creating extra thickness. (AKA dimensional or architectural) Lock Shingles – a shingles with a mechanical locking feature. These are not common. Low Slope Application – method of applying shingles on slopes between 2 and four inches per foot.
What is slope in roofing?
Slope – the degree of incline of a roof plane. Soffit – the finished underside of an eave. Soffit Vent – An under eve opening needed for intake of outside air. These are not part of a typical roofing job, but are needed for good attic ventilation. Soil Stack – a vent pipe that penetrates the roof.
What is the butt on a roof?
Butt – the portion of the shingle exposed to the weather, sometimes called the “tab” of the shingle. Cant Strip – a 45 degree beveled wood, fiberboard, or metal strips at the junction of the roof and a vertical surface used to break a right angle. Primarily used in low sloped roofing.
What is a class A shingles?
Caulk – a substance used to fill a joint or void. Cement – a substance, when cured, binds to surfaces together. Class “A” – the highest fire resistance rating for roofing as per ASTM E-108. Shingle with this rating should withstand severe exposure to fire from sources originating outside the building.
What is roof shingles?
Roof shingles are the top layer of your roof’s defense against the elements. Your choice of shingles should take both function and aesthetics into consideration. Common types of shingles include:
What is underlayment on a roof?
Underlayment creates a barrier between your roof’s deck and shingles. Underlayment material waterproofs and weatherizes your roof. High-quality underlayment sheds moisture, which prevents mold and water damage. Contractors use synthetic weatherproofing materials such as fibreglass for underlayment.
What is a coursing roof?
Coursing refers to the pattern of shingles on your roof. On most roofs, shingles lay in straight, overlapping lines across the length of a roof. Coursing changes according to the shape of the roof. For example, a domed roof may have graduating circular coursing or shingles may be applied in a continuous spiral.
What is a soffit?
Installed beneath of the overhangs of a roof, soffit is the connection between your roof’s fascia and your home’s siding. Soffit may be vented or unvented. Vented soffit draws air into the attic space and is part of healthy ventilation. In the absence of vented soffits, intake vents may be used as a substitute.
What is a fascia board?
Fascias are the boards around your roof’s perimeter. Fascia is attached at the edge of the roof and extends below roof level. Fascia boards protect the roof structure and home interior from damage. Fascia is pre-painted to match the colour scheme of the home and adds a significant aesthetic to a home.
What is a roof vent called?
Your roof may have an exhaust vent which runs along the peak, known as a ridge vent. Ridge vents create ventilation through the attic space. Most ridge vents include an external baffle, which deflects prevents rainwater and snow from leaking into the attic.
What is the deck on a roof?
The deck of your roof lies on the truss frame. The deck serves as the foundation for the rest of the roof. Modern construction most commonly uses wooden 7/16” OSB (oriented strand board) as decking, though older homes may have different material. Your deck should not be visible after construction.
