Do You Need Gutter Flashing? How To Decide

Giovanni Valle is a licensed architect and LEED-accredited professional and is certified by the National Council of Architectural Registration Boards (NCARB). He is the author and managing editor of various digital publications, including BuilderSpace, Your Own Architect, and Interiors Place.

Summary: You may need gutter flashing if you have a low-pitched roof, wooden fascia boards, older gutters, an old home, or a brand-new roof. In addition, gutter flashing is necessary for people who live in rainy or stormy climates.

Gutter flashing is an unsung hero as it works behind the scenes to protect your home from water damage. However, it can be challenging to tell when to install it.

In this article, I’ll talk about gutter flashing and help you understand when it might be necessary to install it. So, let’s get into it!

What Is Gutter Flashing?

Gutter flashing is a strip of plastic or aluminum that fills the gaps between your roof and the gutter. This barrier ensures that rainwater runs directly into the gutter and not behind it.

Also known as a drip edge, gutter flashing helps improve your gutters’ efficiency, and almost any roofing expert can install it.

With continuous exposure to moisture, your home’s siding can become damaged and rot. Gutter flashing ensures water won’t flow down your roof onto your siding, protecting you from moisture accumulation.

Ultimately, this stuff can save you a lot of time, energy, and money spent repairing your house’s siding.

Types of Gutter Flashing

Gutter flashing can be plastic or aluminum.

Aluminum gutter flashing is more costly but lasts longer. However, plastic gutter flashing is more flexible and can quickly adapt to your gutter’s shape.

In addition, there are two kinds of gutter flashing– in-gutter flashing and drip-edge flashing.

In-Gutter Flashing

In-gutter flashing is also sometimes called kick-out or diverter flashing. It’s inserted at an angle to encourage rainwater to flow from the roof into the gutter. It is typically wide enough to block the rainwater from entering underneath the shingles and prevent it from flowing behind the gutters.

When installing in-gutter flashing, you can ensure that rainwater flows into your gutters, preventing water from pooling.

Water accumulation in your yard damages your landscaping but it can also seep into your basement or home’s first floor. So, when you use these types of flashing, you can also keep your home looking its best.

Drip Edge Gutter Flashing

Drip edge gutter flashing is installed at a right angle to your roof and is considered the most crucial tool to protect your roof from rotting or damage.

Your house’s fascia boards support the gutters, and if they become damaged and rotten due to water damage, they’ll no longer hold up the gutters effectively. That makes drip edge gutter flashing even more vital.

Before installing the roof shingles, the roofing professional will place drip edge flashing along the bottom of the roofline. This process forms a seal between the roof and the shingles, preventing rainwater from flowing back into the shingles and helping prevent water leaks.

When To Consider Getting Gutter Flashing

Gutter flashing is not mandatory but forms part of the building code for newly built homes in many states.

Your roofing expert will likely recommend gutter flashing to be on the safe side, but you may be concerned about the cost. However, specific criteria make it a necessity:

You Have a Low Roof Pitch

If your home has a low-pitched roof, it is more challenging for rainwater to drain, and without a watertight and efficient guttering system, the siding is more likely to become damaged by water.

To avoid having to replace the siding and to prevent a potential health hazard due to mold build-up, it’s worth considering installing gutter flashing for your low-pitched roof.

In-gutter flashing is particularly useful if you have a flat or low-pitched roof, as it encourages rainwater to move into the gutter.

Your Roof’s Fascia Boards Are Wooden

Your home may be more vulnerable to moisture damage depending on its fascia material and condition. Stucco and brick are less prone to water damage, but you should treat or paint wooden fascia boards to prevent moisture exposure damage.

You should strongly consider installing gutter flashing if you have untreated timber fascia boards.

Alternatively, you could treat the fascia boards, but installing it may be more effective as this prevents water exposure in the first place.

You Live in a Rainy or Stormy Climate

If you live in an area that experiences high rainfall or frequent storms, protecting your home from rain and wind damage is crucial.

During heavy rainfall, gutters can overflow, causing some of the water to splash onto your home’s siding, but gutter flashing can help mitigate this problem.

You Are Getting a New Roof

Roof installations are pricey, and many homeowners like to do all they can to make their roofs last as long as possible.

Some shingle roofs have tiles extending a few inches over the roof edge. Gutter flashing can support these shingles and prevent them from moving, cracking, or curling.

It’s worthwhile inspecting your shingle roof to check if the tiles overhang in such a way that they allow water to drip into the gutters. Roofs with tiles extending over the gutters would benefit from gutter flashing.

If the space between your roofline and gutter is large enough to accommodate small animals or pests, installing gutter flashing will seal it closed and prevent damage to your roof and fascia.

Your Gutters Are Getting Old

Another vital element to help you decide if you need gutter flashing is your current gutter condition.

As gutters get older, they may start to sag, come loose, or deteriorate. When this happens, they may bend away from your roof, leaving gaps where water can leak in.

If your older gutters are still reasonably good and function well, gutter flashing can fix this problem and is much less expensive than replacing your gutters.

Your Home Is Older

Gutter flashing is now almost always included in newly-built homes. If your home was built after 2000, chances are it already has gutter flashing.

However, the older your house is, the more likely it will require gutter flashing.

Some older homes have inefficient guttering systems with visible spaces between the roofline and gutter, making them vulnerable to water damage.

Final Thoughts

Most roofing experts recommend installing gutter flashing for optimal protection from moisture damage.

However, if you find them pricey and want to avoid investing in gutter flashing, you could avoid it if you live in a low rainfall area, your gutters are currently well-installed, and your roof pitch is steep.

In most states, it’s a requirement for newly-built homes to have it. Older homes may have gaps between the gutter and the roofline, allowing moisture and small animals to enter the roof and fascia boards. In such cases, it might be worth installing.