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Metal Shingles Roofs vs. Standing Seam

Metal shingles roofing systems are a very popular choice for a residential metal roof, and although they are not as common as standing seam metal roofs, they nevertheless represent a significant chunk of the total number of metal roofs installed each year.

steel-shingles-roof

Metal roofing shingles come in many styles, colors and metal options and profiles. Two of the most common types of metal shingle roofs are interlocking shingles and overlapping tiles.

Metal shingles are true architectural metal roofs, and can provide you with a long lasting roofing solution and looks of natural slate, clay tiles or cedar shingles at a fraction of the cost and a much longer roof life.

Metal shingles vs. Standing Seam

Most interlocking metal shingle roof systems are also VERY flexible when it comes to their installation. Metal shingles and can be on some of the most difficult and cut-up roof designs. You can easily roof around a hexagon tower with metal shingles, while the same would be nearly impossible to do with standing seam metal roofing panels.

Flashing a roof penetration such as a pipe flashing or even sky-light or a chimney is a breeze compared to the same procedure using standing seam or stone coated steel tiles roof. Because of low panel profile (average interlocking shingles metal roof sticks about 1/4″ to 3/8″ from the roof deck) metal shingles flashing is easy to fabricate and install in the field.

As you can see in the video above, the chimney flashing (as well as skylight flashing) on a metal shingles roof is rather simple, compared to that of standing seam metal roof, which you can see in the photo below:

The chimney flashing photo below shows a standing seam metal roof with a chimney located on the ridge line, which makes the flashing detail much simpler and eliminates the back pan flashing, which is the weakest point of this flashing detail.

standing-seam-metal-roof-chimney-flashing

The elimination of ribs (r-panels and/or vertical snap-lock or the seam on a standing seam metal roof) makes the flashing detail using metal shingles for both chimney and skylight, a breeze.

How metal shingles are manufactured:

Metal shingles are made in factory settings using a stamping manufacturing process on an industrial size press. A special dye stamps the metal shingle profile, while two additional dyes bend the locks on all four sides of the shingle.

Metal shingles are stamped from a steel, aluminum or copper coils of certain thickness. Steel and aluminum coils are usually painted with 7-layer bake-on Kynar 500 paint finish, which provides the longest lasting discoloration and peel/chip resistance and eliminates the need to paint your metal roof every 5 or so years.

All accessories for a metal shingles roof system are made using either a rolling or bending process on a computerized brake. These are your drip edge, side-wall / head-wall flashing, valley pan, etc.

The ridge / hip caps are usually also stamped out of the same coil used to stamp shingles. A 10 foot field-fabricated ridge-cap section can also be used, with exposed of concealed fasteners.

Metal Shingles Roof Installation:

Metal shingles should be installed over a solid sheeting deck such as CDX plywood or OSB board and proper underlayment such as GAF DeckArmor breathable synthetic roof underlayment sold at Lowe’s for about $100 per roll of 400 square feet. Try to stay away from non-breathable underlayments and Ice & Water shield with metal shingles roof, as they trap moisture and may cause roof deck rotting.

roof-plywood-deck

If your deck is 1×6 boards or similar, you may run into problems with installing and nailing metal shingles. If the row of shingles lands on the crack between boards, your nails will not have a solid substrate to be nailed into.

A solid working solution in the above situation may be using longer clips, that extend past the crack between the boards, or installing a layer of 3/8″ plywood or OSB over the boards.

Using long clips will however result in weaker fastening and lesser pullout / wind uplift rating for the metal roof. Installing a layer of 3/8″ sheeting is a preferred method.

Metal shingles are fastened to the roof deck with nails and either clips or built-in nailing strip on the metal shingle. There are various types of metal shingles and each has its own fastening method, though they are rather similar to each other.

Metal shingles should be nailed to the roof deck, using nails made out of the same metal as the shingle. Thus a steel metal shingle is nailed with regular galvanized roofing nails, and aluminum metal shingles are nailed with aluminum ring-shank nails.

Metal shingles are installed from the bottom, going up. Direction of shingles placement is dependent on the shingle design, but most metal shingles systems are installed from left to right. Each metal shingle is locked into the locks of 6 neighboring shingles, making the whole system very durable and resistant to high-speed winds.

As shown in the video above, an aluminum metal shingles roof is installed over a properly prepared roof deck, and nailed down with aluminum ring-shank nails, through special “ears” or nailing strip built into the metal shingle. Other systems will have different nailing detail such as clips, or a nailing strip going across the top of the shingle.

Metal Shingles Cost Considerations:

Metal shingles roofing is usually made from steel or aluminum, and on a rare occasion you will see a copper or zinc metal shingles roof. The reasons for using steel and aluminum are the facts that both metals are very durable and long lasting (assuming the steel is properly galvanized using G-90 or Galvalume). Steel is somewhat cheaper than aluminum, but difference is not very significant, and much of roof installation cost comes form professional installation as well as a rather high cost of metal.

Copper and zinc metal roofs are generally very expensive and therefore not as popular as steel or aluminum roofs. Installation costs for either type of metal roof will vary from one region to another, but in general, metal roofing prices are much higher than asphalt shingles roofs.

As compared to the cost of standing seam metal roofs, metal shingles shingles are considerably less expensive, as they are made from thinner gauge metal, and are easier to install.

Corrugated Metal Roofing and Ribbed Metal Roofs (R-Panels) for Homes

Modern advances of coating steel sheets with a layer of zinc and aluminum, make corrugated metal roofs a viable economical alternative to conventional roofs, and premium metal roofs.

Corrugated Metal Roofing Panels

Corrugated metal roofing systems available today offer high degree of corrosion resistance, energy efficiency, and economical sustainability.

Many corrugated steel roofing sheets contain over 30% of recycled steel post consumer content, which qualifies it for LEED credit awarded by the green building council.

There are also high quality paint finishes available for corrugated metal roofs. High quality Kynar 500 paint finishes applied over corrugated metal roofs will make this type of system cooler temperature-vise, more energy efficient, and long lasting. Energy savings of over 30% can be attained with the use of ultra cool metal roofing systems.

Corrugated and Ribbed (R-panel) metal roofs are usually made out of G-29, or G-26 (G-26 or smaller gauge is actually thicker and better for residential uses), galvanized steel sheet roofing panels with exposed fasteners.

Corrugated steel roofs are energy efficient, environmentally friendly, green and most importantly affordable. Made out of a relatively thin sheet metal, corrugated metal roofs costs less than metal shingles, and standing-seam metal roofs. They can be a practical alternative solution for commercial, agricultural, industrial, and sometimes residential buildings.

corrugated metal roof on a ranch house

Corrugated metal roofs are comprised out of corrugated sheet roofing panels that are 32 to 36 inches wide. The panels are connected in a side by side overlapping fashion.

To attain water-tightness, the caulk has to be used at the points of overlap in between the metal panels. Corrugated steel panels are secured in place by exposed fasteners.

The disadvantage of using exposed fasteners is that the water may leak through if the fasteners become loose.

Did you know? To keep corrugated metal roofing watertight, the exposed fasteners often must to be re-tightened every 10 – 15 years. Therefore, this is not a maintenance free roof.

The main advantage of a corrugated metal roofing system is that it is relatively cheap compared to the price of metal shingles and standing-seam roofs. You can cover a large roof area with corrugated metal roofing.

As with most metal roofs, there are premium material choices available for corrugated roofs. For instance, you can get aluminum corrugated sheet roofing panels, which will last longer than steel.

There are also stainless steel corrugated panels available to you. Of course, this will cost slightly more, but the higher price may be justified by the fact that you will have a longer lasting roof.

Although, corrugated sheet roofing systems are primarily used for agricultural, industrial, and commercial uses, they can also be used for some residential homes.

If you are planning to save money on the installation of a new metal roof, then consider installing a corrugated metal roofing system made out of G-90 Galvanized Steel, Galvalume steel, or aluminum. Be sure to select a system coated with a premium cool roof rated color finish to ensure a long lasting and reliable service of your new roof.

Corrugated Steel Panels

As a last word of advice, I would like to remind you that corrugated metal roofing systems are very competitively priced, and the cost of labor to install it will be your biggest expense.

Therefore, it makes a lot of financial sense for you to pick a longer lasting corrugated metal roofing system for your home, garage, or shed. Be sure to choose Galvalume steel, galvanized G-90 steel, zinc, or aluminum in favor of a less expensive G-60 galvanized steel. Also, be sure to select a system that has a premium paint finish.

How a Metal Roof is Manufactured

When you see that sparkling new metal roof up on your home, or a house you drive by, do you ever wonder how it was actually made and what goes into the process of manufacturing a metal roof?

standing-seam-metal-roof

A standing seam metal roof is the most popular of all metal roofing systems, in part because it can be roll-formed by roofing contractors on a job site, or in a sheet metal shop, to the exact specs provided by the contractor. In other words, you don’t need to “deal” with big manufacturers when getting a standing seam roof.

But lets take a step back and actually explore the manufacturing process of a metal roof, from the iron ore mine to your roof.

Roll-forming Standing Seam Panels

All standing seam metal roofs go through a roll-former – a machine that turns a metal coil into actual metal roofing panels. The roll former machines can be outfitted with different panel profiles, mechanized or manual shears, computer controller unit, portable or stationary platform / trailer, uncoilers, built-in 10,000 watts generator, and other upgrades, depending on the purposes of its use and how much you want to spend.

MetalMan Roll Forming Machine by Englert Inc. - Source www.englertinc.com
MetalMan Roll Forming Machine by Englert Inc.

The basic process of making standing seam panels involves feeding metal coil into a roll-former. – Once inside a roll-former, the metal coil goes through a series of rolls, which make bends and curves. – Each successive roll makes more of a bend than a previous one. These rolls are made of hardened stainless steel for increased lifespan and durability. Some can bend a metal as thick as 22 gauge steel.

The rolls make up different standing seam profiles, such as Snap-Lock standing seam, Snap-Lock with a nailing strip (no clips required, when fastening these metal panels to the roof), Mechanical Lock Profile, R-Panel, V-5 Crimp panels, and many other exotic profiles.

A panel width can be manually set on each roll-forming machine, but typical widths are 12, 16 and 20″ wide panels. Panel width is actually dictated by a metal coil being used. For a 12″ wide panels you need a 16″ coil. The “extra” 4 inches are not shaved off inside a machine – they actually go into making the locks on each side of the panel.

The computer control unit takes care of the machine operation / speed, panel length, etc. A smart control unit with automatic shear, can pretty much automate your manufacturing process, by running the coil at specified speed and cutting it at specified length.

For example you can program it to produce 10 panels at 28′ 3″ and 25 panels at 24′ 6″ and it will do just that – at required length, the machine stops, the automatic shear cuts off the panel, you pull it out and the next panel starts rolling out of the machine.

Sheet Metal Shop

Besides the actual metal panels, there is also a lot to manufacturing a metal roof that escapes the eye – namely, making all the accessories for a metal roof: the drip edge, rake / gable trim, valley pans, ridge cap, z-bar flashing, sidewall and head-wall flashing for roof to wall connection, chimney and skylight curb flashing, etc. All of these items require precision manufacturing and are absolutely necessary for any type of vertical panel metal roof.

All these metal roof flashing is made in a sheet metal shop, on highly sophisticated, computerized sheet metal brakes, which can also be programmed to increase the speed of making the most popular profiles of metal roof flashing.

The way that a computerized brake is different from a manual or a hand brake is that when using a manual brake you have to manually measure, mark and set up the depth for each bend to happen, and you have to do it on each side of the metal strip to be bent. While this is a viable option, it is very slow, labor intensive and not very precise.

The computerized or automatic sheet metal brake, which is a necessary attribute of any good sheet metal shop, has special “fingers” or stops that will let you insert a strip of metal only so deep inside the brake, and the hydraulic bender, will make the bent. These computerized brakes are very heavy duty and can easily bend metal that is 22 gauge or thicker.

Even a 3/16″ thick metal (aluminum and steel) can be bent in a heavy duty industrial brake, but for metal roofing it is an overkill, as a typical thickness rarely exceeds 24 gauge metal in residential application and 22 gauge in commercial profiles.

Besides a sheet metal brake, a metal shop needs an automated hydraulic shear to cut strips of metal to the required width, so that a brake operator can quickly produce required components and not worry about having the pieces of metal cut.

Beside the shear, the break, and other smaller specialty tools, each sheet metal shop has some heavy duty racks, where the metal coils, sheets of metal and already produced flashing accessories are stored, and a fork-lift to load and unload all the coils and other heavy stuff. Shop workers cannot lift a typical 2,000 or 3,000 lb. metal coil on their own.

sheet metal shop

The bottom line is that running a metal roofing panels manufacturing facility is quite costly, and all work must be coordinated between the guys that make the panels and the sheet metal shop.

Most of the time, to simplify things, the roll-forming machine is located in the shop, on the transportable trailer, and is only taken to a job-site when the job is far from the shop, and panels are too long to be transported by conventional means.

Often, metal roofing contractors who own a roll-forming machine, and manufacture their own standing seam panels, employ an independent sheet metal shop to produce their flashing and accessories, as running a fully equipped shop can be afforded only by bigger, commercial size roofing contractors.

Manufacturing Sheet Metal Coil

We will actually skip the process of converting iron ore into iron / steel, processing and purifying it, etc. Instead, we will start with manufacturers of sheet metal roofing coils, and what they do.

First of all, metal roofs can be made from steel, aluminum, zinc, copper, and even stainless steel. However, galvanized steel and aluminum are the most popular metals, and we will concentrate on these two.

There are about four or five large suppliers of metal roofing coil in steel, and two or three in aluminum, with smaller players picking up the slack.

sheet metal coil

All of these guys basically take a thick metal coil, and run it through rolling machines, to reduce the thickness to a required grade – usually 29, 26, 24 and 22 gauge in galvanized steel, and .032″ / .040″ in aluminum.

The steel coil also undergoes a hot-dip galvanization process, where the coil runs through a pool of boiling galvanic mix of molten zinc (G-90 galvanization) or a mixture of zinc and aluminum (Galvalume).

Once the coil is dipped in the hot galvanic metal, a thin galvanization layer is formed all around an otherwise highly corrosive steel.

Then the coil is run through an annealing machine, which is basically a hot furnace with cooling tubes and ammonia gas inside the chambers.

Annealing softens the metal, which can then be easily rolled down to the required thickness. Aluminum coils do not require galvanization and just go through an annealer machine, before getting rolled down.

Applying Solar Reflective Paint (Kynar 500) is done once a metal coil has been galvanized and cleaned. The coil is then fed into a special “painting machine”, which is a series of separate units, each responsible for its own operation.

First, the coil is thoroughly cleaned and dried. Then it goes through a primer application chamber, where primer is applied to both sides of the coil. Then it goes through a baking chamber where the coil is dried at a high temperature, and primer is baked on. Then another primer and bake-on drying process happens for better, more even primer application.

Once the coil has been primed, and primer has cured in the “baking” chamber, it goes through the painting cycle, which is essentially the same as priming, only the main color is added to the coil in two layers on top. Usually a white coat is added to the underside of the coil, which once again goes through the baking / drying cycle.

Manufacturers

Once the coil is painted, it gets shipped to various metal roofing manufacturers such as Englert, Fabral, PAC CLAD, etc. – These guys slit the coils to their standard widths and cut them into smaller coils – usually 1,000-3,000 lbs., instead of huge 10,000 lb. coils, which come from coil manufacturers.

These smaller coils are then either formed into different types of metal roofing panels or sold off to smaller sheet metal shops or contractors with roll-forming machines, who either install them, or resell them to metal roofing contractors.

The bottom line here is that most standing seam metal roofs are virtually the same product, as most of them use standard Snap-Lock or Mechanical Lock profiles (under different names of course), and the coil usually comes from the same three or four places. The difference is in price, warranty and manufacturer-specific custom panel profiles.

Other than that, as long as the coil comes from a household-name supplier, it does not matter who produced your metal roof. What really matters is the quality of installation.

Then again, I myself have seen aluminum metal shingles with chipping and peeling paint.

On one roof made by a company out of Canada, each shingle had paint peeling off at exactly the same spot as others, which leads me to believe that the coil was not painted properly on one side.

Another example is of another, smaller metal shingles “manufacturer” out of Canada, whose aluminum metal shingles would also lose paint, as it would easily come off when scratched with a finger nail.

This manufacturer would not warranty the product, and stopped responding to the complaints of the homeowner.

The two examples above indicate that a proper warranty is still important and you want to have your metal roof come from a respectable company that will honor their warranty obligations.

Just to give you some peace of mind, these cases with paint defects are EXTREMELY rare, and most steel metal roofs (especially the cheaper 29 gauge steel with acrylic paint) will rust before the paint comes off. — That’s why it’s important to buy a premium product, if you want a premium service out of your metal roof.