Replacing or putting up a new roof can be one of the most expensive and involved tasks you’ll take on as a homeowner. If you’re looking to cut costs of a metal roof installation, and are willing to take the necessary time, then DIY metal roofing is definitely within many homeowners’ abilities. Here, we’ve outlined all the necessary information you’ll need to improve your existing roof and a step-by-step guide for metal roof installation.
Installation Requirements For New Metal Roofs
As with any home renovation, you’ll need the right tools and materials for the job. Here is a full list, along with basic pricing information.
The list of needed tools for metal roof installation includes basic implements that most basic toolkits should have and more specialized items that you’d find in a roofing contractor’s arsenal. We’ve listed them all here.
- Basic smooth-faced hammer
- Tape measure (preferably 20 to 30 feet)
- Chalk line: You’ll need this to ensure that your roofing panels and underlying weather shielding are correctly aligned. Here is a quick tutorial on how to snap chalk lines.
- 24″ x 16″ square
- Aviation snips (left and right-facing): These are necessary for cutting your chosen roofing material.
- Riveter: This will be used to punch in rivets and join your metal roofing panels. Depending on your roofing panel manufacturer’s recommendations, this may not be necessary. Self-tapping screws can be a viable substitute for rivets. For our purposes, self-tapping screws will be used.
- Duckbill vise grips: You’ll use these to crimp panel edges together while riveting or screwing them in place or to bend a panel edge over your roof’s drip edge. 12 or 18-inch panel-bending tools such as this one can also be extremely helpful.
- Caulking gun: High-quality caulk, such as Weathermaster Metal Roof Sealant, will ensure that your roof remains leak-free well after installation. You’ll be using this around panel edges and screws or rivets.
- 12-inch tin snips: For longer straight cuts through any kind of metal, a pair of heavy-duty snips is a must.
- Adjustable-torque handheld drill
- 24′ – 32′ ladder
- Utility razor
Tool breakdown from The Metal Roofing Channel
Installation Materials Required
Now that you’re aware of the different tools you’ll need, you’ll need to write down a checklist for all the materials that will go into your metal roof build. They are as follows:
Metal Roofing Panels
Different types of metal roofing will come with varied price points. Whether you go with corrugated metal roofing or metal shingles, you’ll find the average price per square foot (not including installation costs) here.
- Aluminum sheets: $3.75 – $4.25
- Aluminum shingles: $4.50 – $4.75
- Copper: $20 – $25
- Galvalume: $1.50 – $2
- Galvanized steel: $3.25 – $3.75
- Standing seam aluminum: $5 – $7
- Standing seam steel: $4 – $4.50
- Roofing nails: We recommend galvanized steel nails, whether you’re installing a steel roof, copper roofing, or aluminum panels. These must extend 3/4 of an inch into your roofing substrate. The exact quantity you’ll need will depend on the type of metal roofing you choose. Your metal roofing supplier of choice will typically provide supply guides with metal roofing panels to help you on your way. For reference, most asphalt shingle roofs require six to ten roofing nails per square foot.
Before installing, you should also consider wind exposure and your area climate, as this will affect how many nails you use. You can substitute these for metal-to-wood screws for certain metal roofing applications, such as corrugated roofing installation.
- Self-tapping screws (#12): We recommend zinc-plated roofing screws, which come in a variety of colors to match your exact roof color.
This video is a basic guide to metal roofing screw placement.
- Metal-to-wood screws (#12)
- Roofing underlayment: This watertight base layer goes over existing roof decking or substrate and will have an adhesive backing.
- Caulking or metal roof sealant: Both butyl tape and caulk will have their uses. When joining two corrugated metal panels together, you should use a strip of double-sided butyl tape at the overlap point to properly seal out the elements. Caulk can be used on most other seal points.
- Ridge caps: Otherwise known as flashing, these are placed at the peak of any A-frame to seal two joining roofing sections. You’ll have to measure the peak(s) of your home and purchase 10% – 15% more than you think you’ll need to account for possible error or specialty cuts.
- Gable trim: Gable trim fits over your fascia on the high sides of the roof — AKA the sides with no gutters. These will typically have a drip edge to help direct water away from your siding.
- Eave trim: Eave trim is most commonly seen on buildings without gutters, such as maintenance sheds or workshops. It functions much the same as gutter flashing and fits over your fascia.
- Sidewall flashing: Sidewall flashing protects the joint between a section of roofing and an adjoining wall. This is most commonly seen on the bottom of dormer windows and at the joining points between garage roofs and multi-story houses.
Step by Step: Metal Roof Installation Process
Now that you have all of the necessary materials and tools in mind and on hand, you’re ready to begin. While installing a metal roof on your own will not come with the typical warranties or hassle-free process of hiring a roofing contractor, it is still a great choice for most homeowners. They can last far longer than their asphalt shingle counterparts and will create a far more energy-efficient home due to fuller shielding from the elements.
Step 1: Obtain Necessary Permits
In most locales, any home renovation project of more than $5,000 will require that you obtain a work permit. Since each area has different regulations regarding this, you’ll have to contact your town or city’s building inspector.
Step 2: Take Measurements of Your Roof Area
No matter the total area of your roof, you should purchase between 10% and 15% more material than what you think you’ll need. This will account for any mistakes and odd cuts you have to make to any material.
First, you’ll have to calculate the slope of your roof. This is a simple “rise over run” number. You’ll have to get on a ladder next to your gable ends. Using a long level, measure from a starting point even with the end of your shingles. At the one-foot mark on your level, use a tape measure to see how many inches up your roof has extended.
A four-inch measurement means that your roof has a slope of 3/12 or three inches of rise for every 12 inches of run.
Next, you can use this slope in conjunction with your home’s footprint to find your total roof area. This will require some simple math, following the steps below.
- Square your roof slope. We’ll use the measurement above. 3/12 simplifies to 1/4. 1/4 squared is 1/16.
- Add 1 to 1/16 to get 17/16.
- Calculate the square root of this number. The square root of 17/16 is 1.03.
- Multiply this number times the footprint of your home (not the total square footage). If yours is 1,500 square feet, then you’ll need 1,546 square feet of roofing material.
- If you’re buying 15% extra to account for error or other factors, you’ll need 232 square feet of extra material, totaling 1,778 sq. ft.
This area measurement method is most effective on simple A-frame roofs. For odd corners or outcroppings, such as dormer windows, simply measuring length and width will suffice.
Step 3: Buy the Correct Materials for Your Roof (Panels, Sealant, Fasteners, etc.)
Purchase the above square footage of whatever roofing material you’ve decided on. Metal sheets will have some overlap, and your 15% overage should account for this. You’ll also need the following.
When purchasing self-tapping screws with washers, your metal type and sheet type will dictate how much you buy. Most suppliers offer installation guides tailored for this. You’ll need #12 3/4-inch self-tapping screws to join panels and #12 1-inch screws to join your roofing panels to the substrate or base wood roofing.
Purchase enough double-sided butyl tape for your roof edges at the peak, eaves, and gables, and account for the above-mentioned 15% error.
Step 4: Tear Down Old Roofing
You may need to rent a dumpster to haul away any waste from the disposal of your old roof and the installation of your new one. Begin at the peak of your roof and methodically work your way across and down.
If any nails are sticking up, either hammer them all the way in or dispose of them if you choose. Inspect your roof substrate as you go.
Once all of your construction debris is ready for disposal or is out of your way, you can begin setting up your workspace.
Step 5: Prep The Area and Make Repairs if Needed
Ideally, your tear-down and workspace prep phases should be done on a dry day so that your roof doesn’t get any water on it after you’ve stripped away the underlayment.
Lay out all of your tools and supplies in an organized manner so that you know where to find everything at any given time.
If your roof planking has any rot or damage, then you should replace it while you’re easily able to. Clear the roof of any debris or dust, if possible, before the next step.
Step 6: Roll Out Roof Underlayment
Roof underlayment material typically comes in rolls that span 100 square feet, with widths ranging between 3 and 4 feet. With the adhesive side down and with a couple of inches of overhang over your gables, begin rolling your insulating material out lengthwise across your roof.
Do this slowly, and try to get it as flush to your substrate as possible. Plan for one to two inches of overlap with each subsequent pass.
Step 7: Install Edging
Your eave flashing will line the bottom edge of your roof, around the same location as your gutters. You do NOT have to remove your gutters for this step. The eave flashing will slightly overhang them to assist with waterflow off your roof.
Eave flashing is sold in ten to 12-foot sections, which should overlap each other by two to three inches and extend over the edge of your roof by the same margin. Overlapping edges will require a line of caulk for sealing. Use tin snips to make necessary cuts on the ends, and fold the excess material over the gables.
To fasten this to your roof, use your metal to wood screws. Starting eight inches from the gables, place screws every eight inches until these pieces are secure. Roofing nails can also be used for this step. Defer to your roofing material manufacturer’s instructions if any have been given.
Step 8: Install Metal Panels
- First, snap chalk lines on your panels to mark screw points. Begin six inches from the top of each panel. Then, snap additional lines every two feet further down. Within each line of screws, the fastening points should be about a foot apart.
- Begin at the peaks of the largest squared sections of your roof. Ideally, each metal piece should extend from the high point of your roof and overhang your eaves by 3/4-inch. You should cut your panels to size before securing them.
- Using your #12 metal-to-wood screws, fasten each panel along the snapped lines.
- Where your panels overlap and join (by three to four inches), use your #12 self-tapping screws to join them at two-foot vertical intervals.
- Next, move on to the less squared-off sections of your roof. Take precise measurements of these areas and cut your panels to size at ground level. The non-vertical edges will be covered by your flashing, so don’t worry if your cuts with the large tin snips aren’t perfect. Remember to account for overlap when measuring these sections.
- Fasten these to the substrate just as you did for the previous sections.
- If you live in an area that’s heavily exposed to the elements, place a bead of silicone sealant before driving in each screw.
Step 9: Install Flashing
Flashing is more or less the finishing touch on your roofing project. These pieces seal off all joints of less than 140 degrees. You can bend these to fit your exact shape needs with the panel bending tools in the list above. It usually doesn’t extend more than a foot on each side of whichever corner it covers.
Once cut to size, securing these should be simple, with one row of screws required on each side of the seam being covered. Since this is a final sealing step, butyl tape or caulk should be placed an inch inside each side of your flashing before fastening.
One metal-to-wood screw placed every 12 to 18 inches with a dab of sealant will suffice.
Common Metal Roof Installation Mistakes
Any DIY project will come with some possibility of user error. This shouldn’t make you any more hesitant prior to installing your roof, as even the best professional roofer makes mistakes on the job. Being aware of these common pitfalls can streamline the process and make for a much higher-quality roof in the long term.
1. Having The Wrong Roof Measurements
The old adage, “Measure twice; cut once,” should definitely be on your mind when measuring your roof. Measure each roof section’s length and width carefully, including any dormers (protruding window sections) or other such areas. When purchasing materials, buying 10% to 15% more than you think you’ll need will help to avoid this and should account for any mistakes made during the project. For reference, the average American home has 1700 square feet of roof space.
2. Leaving Worn Shingles Under Your New Roof
While you can leave existing shingles on your roof before installing your new panels, it isn’t recommended if there is any noticeable wear present. Since you’ll be screwing your new panels or shingles into this material, existing wear will greatly weaken the integrity of your new roof.
3. Not Using Underlayment
Underlayment will typically be needed to meet building codes for any roofing project. It is also highly recommended for any DIY metal roofing system. The synthetic material used to make this adhesive-backed material is watertight, which will take pressure off if you can’t install your entire roof in one go.
4. Using the Wrong Sealant
The use of a silicone sealant is necessary for any successful roofing project. Loctite and Titebond are both great options for this. Such materials will expand and contract as your roof does and will last a long time in any climate. Using low-grade sealants can cause leaking and corrosion long-term, which can be easily avoided.
5. Poorly Installed Flashing
Flashing is any section of roofing that covers panel joints or roof edges. They make for full-sealed joints, minimize leaking, and make for nice aesthetic touches in many cases. Flashing can also smoothly mark a transition in pitch, as seen in this video:
6. Over or Underlapping Panels
All panels should have a 1/2 to 3/4-inch overhang past the edge of your roof. When joining panels, most roofers recommend a 1.5 to 2-inch overlap. Doing this and properly sealing panel joints with caulk and fasteners will make for leak-free roofing.
7. Under or Overtightened Fasteners
As a general rule of thumb, your screws or fasteners should extend around 3/4-inch into your roof sheathing or base roof decking boards. If you’ve selected the proper length of screws and fasteners, then over-tightening them once the screw or fastener heads are flush with your roofing panels or shingles won’t further seal your roof. In fact, they can structurally weaken your metal panels or cause small cracks or gaps, which will not be readily apparent.
Today’s Homeowner Roofing Methodology (Roofing Type)
Arranging for a home repair of this scale is going to be a fairly involved project. If you haven’t conducted renovations like this – either via a contractor or on your own – then it can be a bit overwhelming. At Today’s Homeowner, we pride ourselves on being able to take all of the guesswork out of the equation for you.
We’ve thoroughly evaluated each roofing type to make your selection process easier. Through exhaustive research into hundreds of different roofing providers throughout the United States and analyses of thousands of individual homeowner experiences, we’ve broken our roof rating system down into the following categories.
All roofs receive an aggregate rating between (0.0) and (1.0). This rating is comprised of six key evaluation criteria, which we’ve outlined below. The rating between (0.0) and (1.0) will correspond to a secondary rating out of five stars, which is displayed more visibly in our articles across this category.
- Durability (.40): With roofs being constantly exposed to the elements, different materials’ relative durability is a key metric that must be considered. If you’re planning on conducting such an extensive upgrade to your home, then your roof’s expected lifespan should be among your primary concerns. We’ve weighed the relative effectiveness of all roofing materials, from asphalt shingles to corrugated metal roofing from different manufacturers in order to determine the most long-lasting options.
- Cost (.25):The nationwide average cost for replacing a 1,500-square-foot roof falls between $6,500 and $16,000. Across the board, you should expect to pay between $4 and $11 per square foot of roofing material. This range will account for your location, material choice and availability, ease of access to and installation of your roof, and far more.
- Contractor Availability (.13): Different roofing contractors in different locales will have varied service offerings. For example, not all roofers are equipped with the requisite skillset and knowledge to install metal roofing. Depending on the kind of roof you want to have installed, your contractor options may be somewhat limited.
- Warranty Offerings (.12): Aside from workmanship warranties, many roofing manufacturers will offer warranties for the panels themselves. Structural failure should be covered by any manufacturing firm for at least 10 years after the installation has been completed, at the panel or shingle’s full value. We grade each roofing type by standard warranty offerings to ensure that you’re covered in this case.
- Ease of Future Maintenance and Upgrades (.05): You should always have contingency plans after any home upgrade. Maintenance is inevitable, no matter the material you use. Whether you’re installing solar panels on a functional existing roof, or are simply replacing a defective panel or shingle, certain materials will be easier to work with than others. Typically, less durable materials will score higher in this category due to their better pliability and workability.
- Customization Options (.05): Any exterior and visible home upgrade is going to have an aesthetic element, aside from functionality. A roof replacement should be an upgrade to the curb appeal of your home. Different types of roofing materials will have varying numbers of style and color options, which factor into our rating.
Metal Roof Installation Considerations & FAQs
Should you hire a contractor to install a metal roof?
Hiring a contractor to install metal roofing is always a good idea. Doing so will help to ensure the quality and longevity of your roof and will come with greatly reduced personal risk. Falling injuries and related hazards are risks that you will have to contend with if you try a DIY installation.
How long does it take to install a metal roof?
This will depend on a few factors. If you’re staging a DIY installation, and have to tear the shingles off your old roof, then you should budget an extra couple of days to get the job done properly. Weather, roof size, and type of metal material that you’re using will all play a part in determining this.
Can you put a metal roof over shingles?
In many cases, you can actually lay down metal roofing over an existing shingle roof. Aside from the durability metal roofs provide, this is one of the many reasons for their popularity among homeowners.
How long does a metal roof last?
A properly installed and cared-for metal roof can have a lifespan of 40 to 50 years. A roof made of asphalt shingles will typically have to be redone after 15 to 20 years, for comparison.
What are the disadvantages of a metal roof?
The main disadvantages of installing a new metal roof are as follows:
- Affordability: Metal roofing materials can cost more than double what a shingle roof would.
- Noise: You’ll only notice this during heavy rain or hail. However, if you live in an area with more extreme weather conditions, then you may want to reconsider your choice of roofing material.
- Color matching: If your roof needs a repair or extension after a long period of time, then finding the exact color of the material you need could be tough. Due to fading from the sun, newer manufacturing techniques, and evolving color palates, you may be hard-pressed to find an exact color match.
- Fastener longevity: Metal roofing expands and contracts with the temperature. This is an intended feature of its design but can cause fasteners and other hardware to wear out over time. These may