Types of Roof Flashings

Roofing Products

Roof flashing is a very important part of keeping your roof in good working order. It provides an extra bit of protection against leaking, heat loss and can even be useful in keeping fires from starting around chimneys. While flashing performs a fairly uniform task no matter where it's used, there are many different types of flashing that can be used on your roof. Each of these types will come with their own unique sets of positive and negative features. Knowing the differences between them will help you to make a more informed decision as you move forward with your purchase.

Types of Flashing

There are two major types of flashing that are used on modern home roofs. The first type of flashing is designed specifically for the purposes of waterproofing the roof in areas that could be susceptible to leakage. The other type of flashing is for the purpose of preventing fires from starting on the roof. When deciding on the type of flashing you need to invest in, it's important for you to understand the inherent differences between these two types. Mistakenly investing in one type when you need another type can end up being a very costly mistake indeed.

Flashing for Waterproofing

This flashing is generally going to be installed at the peaks, valleys and edges of your roof. Basically, this flashing is used at any point where two planes meet at different angles to produce a joint. These joints can have miniscule amounts of space between them that can allow water to seep through over time. Waterproof flashing can prevent this seepage from ever occurring and it can make your roof last much longer. After all, water getting under your roof can lead to damaging rot that can be horrifically expensive to fix if left unattended.

Internal roof flashing is used underneath your roofing material to prevent water from leaking into your roof or home. It is generally constructed out of a high-density plastic material that is designed to provide years of use. The only problem with using internal roof flashing on its own is that water needs to go through the shingles to get to the internal flashing. This doesn't protect the shingles themselves from being rotted out from underneath as water gets underneath them.

To protect the shingles from being rotted away by consistent leakage, external flashing is used as an extra barrier. External flashing is generally constructed out of a waterproof membrane that prevents water from penetrating through the topmost layer of roofing material. This can be anything from a membrane that is applied as a liquid polymer or even a single v-shaped covering that goes over the joints in your roof. This "dual layer" approach to waterproofing will generally have the highest rate of success and will provide the most comprehensive protection. In some cases, this approach is simply a smart investment that is more of an add-on to a roof. In other cases, dual flashing is a requirement for a roof to be brought up to code.

Flashing for Fire Mitigation

Chimneys for fireplaces and vents for wood stoves can get extremely hot when they are in use. Metal chimney flashing is used as a way to both waterproof the area around the chimney and diffuse the heat generated by the fireplace itself. This heat diffusion can be an essential part of protecting your roof from catching fire when your wood stove or fireplace see heavy use. However, it's important to note that the heat diffusion aspects of this type of flashing are not the only reasons to use it.

Your chimney or wood stove vents need to be waterproofed as much as possible to prevent rotting of the thermal paste used to separate them from the flammable material of your roof. Over time, water seepage can create fungal buildup that can degrade the integrity of the insulation surrounding your chimney. As this insulation breaks down over time, it can put your roofing materials at risk for fire damage. This is why it's so important to keep the flashing around your chimney or wood stove vent in the best shape possible. Keeping out water and diffusing heat from these sources can have nothing but positive results.

It's a Straightforward Purchase

Unlike many other choices that go into various home remodeling jobs, purchasing flashing for your roof is a fairly simple process. The available types of flashing are all fairly similar in quality and usability. As long as you're working with a qualified contractor who can point you to reputable dealers for flashing, you should be able to make this decision with relative ease. In the end, you may find that the process of purchasing roof flashing is one of the most straightforward, common-sense purchases you'll make for the health of your home.

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