You can’t overthink the overhang
There’s no building code requirement for metal roof overhang, but a 1-inch to 3-inch overhang is standard.
You should base your metal roof overhang on your local climate and aesthetic preferences.
Roof overhang will help protect your fascia boards and roof decking from water, so it’s a crucial part of the roof system to get right.
Your roofing system is one of the most crucial parts of your home to make sure you get right. There are building codes for most aspects of roof installation and design, including the depth of your eaves and even where you place fasteners, but one area where the code is lacking is the roof overhang. While there’s no specific measurement required, between 1 and 3 inches is standard for metal roofs. In this guide, we’ll explain how to determine the ideal overhang for a metal roof and why it’s important.
Homeowners and contractors alike use the term “roof overhang” to refer to a few things, so a little clarification is in order before we get into the ideal roof overhang on a metal roof.
Eave overhang: “Roof overhang” can sometimes refer to how far your eaves extend beyond your exterior wall at the bottom of your gables. A more specific term for this is “eave overhang,” and the standard measurement is 12 inches. Building code requires under 24 inches unless the builder uses additional bracing for support.
Rake overhang: Some people use “roof overhang” as a general term for rake overhang, which is how far beyond the exterior wall your roof extends on the rake edge (the sloped side of a gable). Standard rake overhang is anywhere from 1 inch to 12 inches, and it can extend to 24 inches without additional support.
Roof overhang: The most accurate definition of “roof overhang” is how far beyond the fascia board your actual roofing material extends at the bottom of your roof slopes.
There are no general building code requirements for how much roof overhang you need on a metal roof. In most cases, though, accounting for between 1 and 3 inches beyond the fascia board is standard when measuring for a metal roof, depending on your climate and the look you’re going for on your home. A shorter overhang looks more modern and sleek, while a longer overhang provides better protection for your roof decking and fascia board, reducing the risk of water damage and rot.
There are a few important things to think about when hiring a roofer and discussing roof specifications to make sure you get the optimal metal roof overhang for visual appeal and property protection.
You can eliminate metal roof overhang entirely to achieve a sleek, modern appearance. Coupling a roof with no overhang with drip edge flashing can still protect your roof decking, although your fascia boards will see more exposure to rain and snowmelt and will be at a greater risk of rotting.
In areas with heavy snowfall and above-average rainfall, you should aim for between 2 and 4 inches of roof overhang, especially if you have a steep metal roof pitch. Doing so reduces the risk of water damage to your fascia and roof decking. You should avoid going beyond 4 inches because longer overhangs run the risk of snow loads bending the roof downward over time, which can detract from your home’s curb appeal.
For the best results and the lowest risk of property damage, consult with your local metal roof installer about what’s best for your area.
If you have gutters installed on your home, a metal roof overhang of 2 inches is ideal for directing water into the gutters for safe disposal. Extending the overhang beyond that can route water over your gutters, rendering them useless.
K-style gutters or half-round gutters are both good options for under metal roof overhangs, and half-round is a better option in climates where heavy rain and snow are common occurrences. Standard 5-inch gutters will do a good job of collecting runoff from a metal roof, but since water flows more quickly over metal than it does over asphalt shingles, upgrading to a 6-inch gutter is best to catch more of the runoff for safe disposal.
A metal roof costs an average of $11,700 to install, which is just under twice as expensive as installing an asphalt shingle roof. Most homeowners pay between $7,500 and $24,000 to install a new metal roof. Your installation price will depend on your home size, roof slope, the metal material you choose, and the type of metal roof you want.
No, there’s no specific building code that requires a roof overhang. However, installing your roof with the standard 2-inch overhang is good practice, as it helps direct runoff away from your fascia boards and roof decking and into your gutters. Some overhang is especially important in areas that see heavy rainfall and snowfall, as the risk of water getting under the roofing material and causing water damage is much higher.