When building a roof for your dream home, one of the most important things to do is ensure that the roof will be as resistant to water as possible.
You can do this in various ways, such as by installing a gutter system to direct water away from the roof, but you should also consider your roof’s drip edge.
What is drip edge on your roof?
Drip edge is metal flashing. It gets installed at the roof edges to ensure you keep rainwater away from your fascia and prevent it from seeping underneath the roofing components.
This is essential to have on your roof because without it water will seep behind your gutters and it can cause your fascia boards and roof decking to rot. With that in mind, let’s explore everything you need to know about drip edges.
What Are The Benefits Of Drip Edges?
A drip edge can be made out of materials such as metal, plastic, fiberglass, or vinyl. It is inherently rust-proof so it won’t be affected by water and comes with many benefits.
A drip edge keeps water away from your basement and porch.
It seals areas on the bottom of the roof that can allow pests to gain access to the inside of your home.
It protects the bottom of the roofing shingles during ice dams. If you don’t have a drip edge, this icy water can drain and cause wood to rot. It can also result in mold growth.
A drip edge prevents any movement from occuring between the fascia and deck boards. This is beneficial during windy days as they will remain stable and secure.
A drip edge directs water into the gutter. This keeps your shingle roof and house foundation in good condition.
Is Having A Drip Edge A Code Requirement?
Drip edges are required by the International Residential Code (IRC) and since most U.S. states follow the same precedent set by the IRC, this means that drip edges are required for most types of buildings in the country.
In fact, 49 states have adopted the IRC, so drip edges are generally required. Based on their benefits we touched on earlier, it’s clear that installing a drip edge is a good move on the part of homeowners.
There are some instances in which a drip edge isn’t required, however, such as in the case of historical buildings. If you have a prebent aluminum fascia that is flush with the decking of your roof, this basically serves the same purpose as a drip edge so you won’t require one.
However, it’s important to check with city hall in your area so that you can stay informed on the codes you need to consider for your home. You could also consult with a home inspector for advice.
How Should A Drip Edge Be Installed?
A drip edge should be installed at the eaves and gables of shingle roofs, in other words at the edges of your roof.
Adjacent pieces of the drip edge should overlap by around two inches. The drip edge should be extended by a minimum of a quarter of an inch underneath the roof decking.
Underlayment needs to be installed over the drip edge, so that it’s along the eaves but underneath the underlayment on your gables.
With that in mind, here are the drip edge installation steps that you should follow.
Note that if you already have drip edges on your roof but they’re damaged and you want to replace them, you should carefully remove them by lifting the roof shingles just enough so that you can see the drip edge. Find the nails that are securing the drip edge and pry them out with a hammer or pry bar, then pull the drip edges out.
Then, follow these steps to install new drip edges on your roof.
Start by installing a drip edge on the roof eaves. Make sure they’re aligned so that water will drip into the gutters. You should slip drip edges underneath the felt underlayment and roof shingles. Make sure every piece overlaps the other by approximately one inch or so.
Use roofing nails to secure the drip edge. Pro tip: make sure you place them high so that the roof shingles will hide them from view.
Next, on the corners where a rake edge and eave meet, make a cut so that you’ll get a proper fit. Put the drip edge on the rake edge first. Mark the spot where the edge overhangs, and an inch further out from where your drip edge starts to overhang. Go ahead and cut the drip edge by the second mark – it should only overhang past the edge by about an inch.
Cut the top portion of your drip edge in the spot where you made the first mark. Then you should make a perpendicular cut to remove a square of the drip edge.
Install your drip edge. The flap of the drip edge should be bent to create a corner. Then you can go ahead and install the drip edge on the roof rakes.
Roll out and install some underlayment after the eaves have been covered with the drip edge. This should be placed over the drip edge on the roof eaves but underneath the drip edge on the roof rakes.
After placing the drip edges on the rakes, you can use roofing nails to secure them. Galvanized roofing nails are always a good idea, but make sure you’re using the correct nails and adhesive as determined by your local code.
Install the rake’s drip edge on the tab, or flap, you made when installing the drip edge on the eaves.
Make a cut on the drip edge on the roof’s ridge. You should do this by holding the drip edge to the ridge and marking where the drip edge exceeds the roof, then cutting.
Fold the drip edge so that it fits snugly over the roof ridge. To make drip edge installation look as professional as possible, you should mark the plumb line and cut the top section of the drip edge all along this line. A roofing nail should be used to keep the drip edge securely fastened.
How Far Should Your Drip Edge Be From The Fascia?
You should ensure that the lower edge of the roof extends from the fascia board by a ¾-inch. This will ensure that water can drain into the gutters.
If the overhang is less than that, the water will seep behind the gutters and this will damage the roof sheathing and fascia, causing them to rot. You could even end up with water in your basement, stained siding, or soil erosion.
How Much Does A Drip Edge Cost?
Since aluminum is considered the standard material for drip edges, this costs between $1 and $2 per linear foot. If you want a copper or steel drip edge instead, these types of metal will cost you more money.
Bear in mind that the cost of your drip edge will also be influenced by the style of the drip edge that you’re going to be installing on your roof. There are three drip edge styles:
Type C. This is an L-shaped drip edge that’s bent at a 90-degree angle.
Type D. This is a style that looks like the letter “T” with a flange at the bottom. It’s designed to keep water further away from your fascia.
Type F. This is a longer drip edge and it’s ideal for installing over your existing shingles, but you can also use it on rake edges.
Can you install a drip edge after your roof has been built?
A drip edge is usually installed at the same time as when your roof is built. If you want to add a drip edge to your roof after it’s already been constructed, this is a bit more difficult.
Can you use roofing cement to secure drip edges instead of nails?
You can secure the drip edges with some roofing cement. You will have to apply a bead of cement all along the top of the drip edge then press down onto the shingle to ensure that it’s been securely applied.
While you might not think about drip edges, they’re an important part of your roof’s waterproofing plan to keep water out of your home as well as prevent other water damage, such as soil erosion.
After reading this guide, you now know how important drip edges are and how to install them successfully.
James Weldon is a professional roofing contractor with many years of experience on the job. He does not only handle large projects and provide excellent services for his company’s many clients; James Weldon also dedicates his spare time to teaching others useful tricks of the trade. Using BuildCampus as an avenue to reach many roofers and aspiring roofing contractors, James Weldon continues to provide high-quality educational posts and buying recommendations for anyone who visits the website.