Metal roofing can be affordable and reflect heat and sunlight away from your home. When it rains, though, you want to make sure that the metal roof does enough to prevent the water from accessing areas that can cause damage. Because of this, you may wonder, “Do I need a drip edge for a metal roof?”
You do not have to have a drip edge for metal roofing that overhangs an inch or more unless required by code. However, we highly recommend installing a drip edge because it redirects water away from the fascia and exterior of your home, looks better, and prevents water intrusion and damage.
In this article, you will learn about the benefits of using a drip edge on your metal roof and the best options available for this purpose. You will also learn how to install your own drip edge on your metal roof and how much it may cost to have it installed.
- Do I Need a Drip Edge for a Metal Roof?
- Why You Should Install a Drip Edge on a Metal Roof
- How Far Should Metal Roofing Overhang Drip Edge?
- Should Gutters Be Installed Under The Drip Edge?
- What Is the Best Drip Edge for Metal Roofing?
- How to Install Drip Edge on a Metal Roof
- How Much Does it Cost for Drip Edge Installation?
- Can You Paint Metal Drip Edge?
Do I Need a Drip Edge for a Metal Roof?
You do not have to install a drip edge as long as you have metal roofing that overhangs the exterior walls by an inch or more. This is because if the roof hangs out at least an inch, then the water will flow away from the fascia, the area that fastens the gutters to the roof and blocks water from getting into the roof deck. The fascia is one of the most vulnerable areas of the roof and water spilling onto the fascia board may contribute to rot and other water damage.
While a metal roof will usually be okay for preventing excessive water from reaching the fascia and other portions of the exterior of the home, over time, minimal amounts of moisture can build up and gradually cause damage. Because of this, installing drip edges on a metal roof is highly recommended.
Most international building codes, like the IRC, only specify and require drip edges on other types of roofs, including roofs with shingles. However, just because the international building codes do not necessarily require a drip edge on metal roofs, it is best to double-check with your county, city, and state building codes as well as your HOA and any other governing bodies.
Just knowing the benefits of installing a drip edge on your metal roof will probably be enough to help you decide to do so.
Why You Should Install a Drip Edge on a Metal Roof
There are a few main reasons why you should consider installing a drip edge on a metal roof, even if the roof overhangs by more than an inch. We cover each of the three benefits: appearance, water redirection, and a seal to any openings.
A drip edge can give a clean appearance to your roofline that many homeowners find looks much better than an overhanging metal roof. It looks cleaner and can provide contrast or extra trim color to your home. This can enhance the curb appeal and provide an appearance that will remain clean and organized for years.
This is the main reason that you should put a drip edge on a metal roof. The drip edge will redirect the water away from the vulnerable portions of your home, specifically the fascia. When it rains, the flow of water will be controlled and directed toward the gutter and other harmless locations. This will help keep water, ice, and snow away from portions of the home that can become damaged with water.
Water damage like this can cause rotting, deterioration, weakness, and warping in the wooden structures of the building. Eventually, the weakened wood will have to be replaced. Otherwise, it can be a safety hazard and detrimental to the life of your roof and your house.
You may think that the metal roof overhang does enough to prevent moisture at the fascia and other susceptible parts of the area. Still, wind, droplets, and other factors can allow the water to access the fascia more than you realize. A drip edge ensures that this does not happen.
A drip edge can also close up some small, seemingly insignificant openings around the roof. These areas can allow access to the attic for water to creep in, but also for bugs, bats, birds, and other critters and pests to invade your home. Your home is comfortable for you and it will be comfortable for animals as well. A properly installed drip edge can prevent animals from seeking out warmth, food, shade, and other conveniences that your house may offer.
How Far Should Metal Roofing Overhang Drip Edge?
Typically, you will want the metal roof to overhang the drip edge by 1.5 to 2 inches. This is because the overhang prevents water from rolling around the edge or using surface tension to creep along the bottom of the metal. If you are using gutters and a drip edge, then as little as 1.25 inches may be sufficient. The maximum overhang you should ever consider is 4 inches, which is too much for many slopes and locations.
Water will roll down a metal roof much more rapidly than it would with shingles or other textured roofing materials. If the overhang is too large, the velocity of the water can launch it too far, past the gutters. This is especially true during heavy rainfall when the water builds up on the roof surface quickly and flows consistently.
Should Gutters Be Installed Under The Drip Edge?
Yes, gutters should be installed under a drip edge. The reason that gutters are always installed beneath the drip edge is to place them so that the water cannot drip behind the gutter or exceed the outward edge of the gutter. The gutter should be installed between 2 and 3 inches away from the roof and the back of the gutter should rest on the lower portion of the drip edge. The gutter also must be installed so that the back end of the gutter wraps on the back end of the drip edge so that no water can escape.
Installing drip edges and gutters in this way ensures that all the water continues into the gutter so that you can direct it toward a downspout. The drip edge needs to be able to redirect the water into the gutter with both a slow and fast flow depending on the accumulation of water from heavy and light rains.
What Is the Best Drip Edge for Metal Roofing?
There are a lot of drip edges to choose from that may be good for a metal roof. Understanding the differences between materials and shapes can help you choose one for your metal roof.
The most common material used for drip edges is aluminum. It is good for metal roofs because it does not corrode and is sold in various colors and designs to match the metal on your roof, the fascia, or the trim. It is also somewhat malleable and still strong enough to withstand a good pressure.
Galvanized steel is another good option if you live in an area with a lot of wind or snow because it is stronger than aluminum. Just make sure that it is at least 24 gauge and galvanized to prevent corrosion and rust. We recommend at least 36 gauge for use with a metal roof.
Plastic, fiberglass, and vinyl drip edges may also be available but are not preferred for a metal roof for a few reasons. First, they are just not as strong and if you want to protect your home from water damage, it is best not to skimp. Two, they will be more difficult to match with the aesthetic of a metal roof along with the exterior of your home. They can be a good option for a shed or other non-livable structure with a metal roof as long as you understand that they can not withstand too much pressure from the elements like other options can.
There are multiple design types for drip edge products as well. Type C is the classic style shaped like an L and usually has a lip or flange at the bottom to prevent water accumulation and reduce the risk of water intrusion toward the exterior of your home. This type works well for metal roofs if you can utilize a furring strip, which is a piece of lumber, usually a 1×2, that you will install on the surface of the house underneath the edge of the roof that will allow the flange of the drip edge away from the outside of the siding. The result is the prevention of water near the house.
Type D drip edges are another type that doubles up to create a lopsided T shape. This keeps water away at a greater distance than Type C. This type is also good for areas with heavy rain, wind, snow, and other extreme elements. It will also go up under the metal roof to prevent water intrusion underneath the underlayment because it installs far over the sheathing.
While these two common types of drip edges can be used for a metal roof, we recommend using hemmed drip edges for metal roofing because it ensures that water does not sneak past the drip edge via wicking. It also works well for metal roofing construction for a secure drip edge that pushes fast-flowing water away from home.
How to Install Drip Edge on a Metal Roof
Installing a drip edge on a metal roof is not difficult if you know how to do it as long as you have everything properly prepared. These steps can be used at any time, during metal roof installation or any time after. Be sure to gather any supplies that you will need before starting.
You will need:
- Drip Edge (We recommend Hemmed Drip Edges)
- Roofing Nails
- Hammer or Nail Gun
- Tin Snips
You will want to start with the eaves by placing the drip edge down and aligning it to drip into the gutters. The end with the flange or flair will point away from the roof and down toward the gutter and the ground. For Eaves, you are supposed to install the underlayment over the drip edge (whenever you reach a rake, you need to install the drip edge over the underlayment).
Start by securing the drip edge as far as it can go under the underlayment or up onto the roof over the sheathing. Then, you can look to see if that placement will allow the water to drip directly into the gutter. If not, adjust it as necessary. You want the drip edge to direct water into the gutter with slow and fast-moving water; otherwise, there will be times when the drip edge does not do its job.
Now that you have the correct placement, you will have to secure the drip edge to the roof. While you may have heard that adhesive or cement can work to secure a drip edge, this is not recommended. Instead, you should use roofing nails.
You will want to use a nail every 10 inches to a foot. Do not have a gap much larger than 12 inches without a nail. When you get to the end of the drip edge piece, you will want to overlap the next one by 1 to 2 inches. This secures it and prevents creeping water from making its way between them should moisture intrude.
When you get to a corner where an eave and rake edge come to a meeting point, you will have to cut the drip edge to make it fit correctly. You can use tin snips to cut the drip edge so that it fastens around the corner and remains effective.
You will want to make the first cut through the top portion where you need it to be malleable around the corner. Cut the section that is supposed to go over the roof sheathing. Then, you will make a second cut on the bottom flange or edge, depending on the type of drip edge you are using. This allows you to bend the piece 90 degrees to fit it perfectly around a corner. Then, you can use small pieces of extra drip edge to fill in the gaps where you made the slits, but it is not necessary to do so.
Now, make your way around the perimeter and when you reach the end, you will have to make sure that you have overlapped portions at every meeting palace of the drip edge. You can then check your work by using a hose and watching how the water flows off of the drip edges. Make adjustments as needed.
How Much Does it Cost for Drip Edge Installation?
Drip edge materials do not cost very much, with aluminum ranging from $3 to $10 per 10 linear feet. You should purchase extra to cut corners and for any mistakes and overlap. Remember, each time you need a new piece. It should go over the previous component by an inch.
If you do the project yourself, you will save all the money for labor. This is usually around $45 to $75 per hour, depending on the contractor or company that you choose. The amount that you will pay for labor will depend on the size of your house, the difficulty of the job, the type of drip edge, and even the height of the home.
Can You Paint Metal Drip Edge?
A drip edge for a metal roof can be attractive, but only if the color matches the color scheme of your home. If you cannot find a color that works for you, or if you have some installed and it does not look as good as you had hoped, then you can paint aluminum or galvanized steel drip edges.
In addition to making it look better, priming and painting the drip edge will seal the drip edge against moisture damage and lay down a sealant foundation that can create a waterproof barrier when using exterior paint.
To paint the drip edge, you will have to make sure it is clean and free of dust and other debris. Then, use an exterior acrylic primer using one layer or two if the coat is thin. Then, the best pain is exterior, waterproof acrylic semi-gloss house paint.
While you do not technically have to have drip edges on a metal roof that overhangs, it is best to do so to prevent moisture accumulation and water damage. Plus, it can improve the curb appeal of your home by making the edge of your metal roof look more clean and organized. Just make sure that you install the drip edge correctly for long-term functionality.