Roof flashing is critical in making sure water does not enter your roof.
Sydney homes receive a battering from the extreme weather conditions it experiences all year round. Heat waves, hail storms, heavy rainfalls, and string wind, can all take a toll on your home, particularly the roof. Over time, these weather events may affect the structural integrity of your home’s roof system, resulting in damaged roofs and leaks.
This is why routine maintenance is important in reinforcing your roof and making its individual parts effective against any weather. One of the most overlooked yet, extremely crucial part of the roof is the unassuming, simple roof flashing.
What is Roof Flashing?
Roof flashing is a small elements of a roofing system. But, it does a significant waterproofing job. Flashing is designed primarily to prevent water from getting into the house through the gaps on the roof. It is estimated that 90 per cent of roof leaks are due to faulty flashing.
Different types of roof flashing protect different areas of the roof. But whatever type they may be, their main function is to redirect water away to prevent leak and damage. Roof flashing is applied to the corners and valleys of the roof, as well as to any object that projects outward from the roof.
Roof flashing comes in a variety of materials, such as:
Aluminium — a commonly-used flashing material. It is lightweight, durable, cheap and easy to apply. It is typically coated to protect it against corrosion.
Lead — soft and pliable, lead is one of the oldest flashing materials used for roofing. It is durable and often used for chimneys due to its reliable protection against water seepage. However, lead comes with health risks and is no longer used as often.
Copper/Lead Coated Copper — pliable, low-maintenance, solders well, and compatible with almost any wood preservatives, copper flashing is the most durable flashing material. It easily adapts to weather changes and lasts a long time, too.
Steel/Galvanised Steel — rust-resistant, easy to apply, and cheap, galvanised steel roof flashing is visually-appealing and can be painted on to meld with the rest of the roofing. It is not as durable a material, however, as others on this list. Thus, it is not recommended in regions with harsh weather conditions.
Plastics, Rubbers, and other Composite Materials — these are also cheap but may not be ideal for areas that experience extreme heat or cold. These can be made from recycled materials.
Certain building codes may require roofing professional to comply with specific standards for flashing. For example, flashing materials used must be manufactured in accordance with AS/NZS 2904. Check your local building codes to make sure your roofing system is compliant with the applicable regulations.
Different Types of Roof Flashing
How many types of roof flashing are there? Well, there is one type for every part of the roof — which is a lot! There’s even a flashing for flashing. All the different types work together. Know more about the key types of roof flashing below:
Continuous/Apron Flashing
This flashing works like an apron between the roof slope and a vertical wall or roof penetration. It consists of a long piece of metal with expansion joints. Its purpose is to redirect water away and carry it down to the shingles.
Step Flashing
This consists of a rectangular metal bent at 90˚ in the centre for a roof-to-wall application. Protecting the transition spots between the roof and wall, this flashing is laid in “steps” — that is, in layers overlapping 2 inches. It redirects water into the gutter. If one layer fails to do its job, the one beneath it will carry on the task.
Base Flashing
Base flashing works with another flashing type, the counter flashing, to effectively seal the vertical and horizontal intersection of the roof. It is typically used for chimneys and walls or parapets. This flashing keeps water from penetrating the roof deck.
Counter Flashing
This flashing complements the base flashing and is entrenched into the masonry to prevent water from getting behind the base flashing. It is also known as cover flashing or cap flashing.
Drip Edging
Applied on a roof’s eaves, this flashing guards against the water seeping underneath the shingles in case of an overfilled gutter. Without it, water can get into your home and damage the roof deck, wood fascia board, drywall, and other roof parts.
Vent Pipe Flashing
This is a special flashing that has a cylindrical body with a flange at the bottom which is fitted over pipes. It prevents water from slipping around the pipes or flues.
Valley Flashing
Shaped like a V or W, valley flashing is placed atop the roofing felt where one of the most critical water leaks can happen — the roof valleys. The roof valley is where two segments of the roof meet forming a dip or a valley. This flashing type guides water down the roof and straight into the gutter.
Saddle Flashing
Also referred to as joist saddle flashing, this is placed over joists, beams, or other protrusions through the cladding.
Common Applications of Roof Flashing
Roof flashing is found all over the roof. These are the crucial areas where flashing is required:
Roof valleys and joints — there are prone to water penetration due to the angles that can easily collect water.
Roof protrusions — these are anything that juts out of the roof such as plumbing pipes, satellite poles, and dormers. Pipe boots fitted around the pipe can help keep water from slipping in.
Chimneys — flashing around chimneys prevents water from collecting and leaking at the base of the chimney.
Skylight — there are skylight installations that come with built-in flashing. Without it, roofing professionals purchase or create flashing for skylights, as this area can be notorious for leaks. Flashing for skylights typically consists of continuous flashing, step flashing, and finally, saddle flashing.
Roof edges — flashing around these areas help secure the roof against leaks by directing the water off the roof.
Kickouts — roofing professionals apply kickout or diverter flashing to reroute rainwater that falls at the lowest point of the joint between the roof and wall and into the gutter.
Roof ridge — flashing is applied to cover the roofing material. It secures the roof apex from water penetration due to rainwater falling at an angle.
When to Call for Professional Roof Flashing Service
Roof flashing is essential for weatherproofing every part of your roof that is vulnerable to leaks. Flashing also provides aesthetic appeal and creates a sharp, seamless finish on the roofing job. It is essential to pay attention to roof flashing during routine maintenance.
Over time, flashing can get damaged and may need replacement. If left unfixed, there may be serious water leak damage that can be quite costly to repair. When you notice signs of damage like holes, corrosion, dried out sealant, or flashing that has bent or come loose, it’s time for a roofing service.
When it comes to roof flashing, you can trust the high-quality products and services from Sydney Roof and Building Supplies. We carry different ranges of flashing for your roof. Contact us so we can discuss how we can help with all your roofing needs.