If you’re looking for a long-lasting durable roofing material for your shed, then metal roofing will be your best option.
Choosing the best metal roofing for your shed involves initial price, longevity, climate, ease of installation, and maintenance or inspection requirements. Corrugated or ribbed steel metal roofs are the most popular for a shed.
If you opt for the more expensive aluminum, you won’t have to worry about scratch damage; however, you’ll still need to inspect the fasteners at times. While aluminum is more expensive, especially in the better grades, it’s almost a no-brainer for a shed roof near coastal areas prone to have salt in the air.
What Are the Different Types of Metal Roof Materials?
There are four main types of metal roofing available, based on the materials used. A fifth type, tin, is no longer in use. When people speak of tin roofing, they are usually referring to aluminum or steel.
Aluminum roofing: Aluminum is the most lightweight of metal roofing materials. However, the ratio of strength to weight is higher for aluminum compared to other metal types. This enables you to get the same strength as a heavier material, allowing you to use a material that’s easier to work with.
The lesser weight also means less load stress on your roof supports. Aluminum is naturally resistant to rust and corrosion, making it a good choice for roofs near coastlines where salt in the air would cause a steel roof to rust.
Since aluminum is a softer metal than steel, it does tend to dent more easily when hail or falling tree debris strikes it. While using a heavier grade aluminum will help with this problem and prevent some dents, the heavier aluminum does cost more. Aluminum roofing in general is not as prevalent as steel roofing. There aren’t nearly as many companies manufacturing aluminum roofing as there are steel.
Unless you live in a coastal area, you may have to have it shipped in from out of state, increasing its cost. This lack of demand and manufacture in general means that the roofing does not come in as many colors as steel. Steel roofing may come in four or five shades of a color, while aluminum will have just one.
Copper roofing: This is a real show-stopper. Besides the unique appearance, the roofing material changes color over time, developing a patina with age, usually a greenish color. This color will vary with the type of climate it’s exposed to.
This patina actually helps the copper resist the elements every more than it already does. Like aluminum, it won’t rust when used near coastal areas. It lasts longer than almost any type of roofing, which is why you will see historical buildings with copper roofs.
Copper is often used as accents on roofing because it is one of the most expensive roofing materials available. However, it is a softer metal than steel and is prone to be dented. Copper roofing usually comes in 16-ounce or 20-ounce copper.
The heavier grade will withstand dents better, but of course, will cost more. Copper roofing can be hard to come by, as many roofing companies don’t keep it in stock. It usually is ordered for specific jobs, which makes your roofing job take a little longer.
Zinc roofing: Zinc has a unique appearance that, like copper, will change color, developing a bluish-gray patina over time. The patina is formed once the metal is exposed to carbon dioxide and moisture in the air. This forms a layer of zinc carbonate, which protects the roof from rust.
Because of this, it is another good choice for use in coastal areas. Some zinc roofing has already formed a patina before it is purchased. Zinc is very long-lasting. While zinc roofing is popular in Europe, it is not commonly used in the U.S. Because of this, zinc is the hardest type of roofing panel to get.
Besides the fact that it is expensive, most zinc roofing has to be imported from Europe, raising the cost even more. Another problem is that sometimes a chalky substance forms over the patina in places where water routinely runs on the roof. While this doesn’t hurt the actual roof, it does create a white streaking that is not very attractive.
Steel roofing: Steel is by far the most commonly used metal roofing material. In fact, when people think of a metal roof, they usually think of steel. Steel roofing is low maintenance and is resistant to rot and fire. Steel is the least expensive of all the metal roofing materials and comes in a wide variety of colors due to its popularity.
Since a steel roof can last three times as long as a shingle roof, the extra cost is made up for in longevity. Steel is also less prone to dents from falling debris or hail than other metal types.
Steel is corrosion resistant; however, if it is scratched by falling debris to a depth that goes below its protective coating, it can start to rust. It is also adversely affected by salt in the air and is not a great choice for people living in coastal areas. It also weighs more than copper or aluminum, so care should be taken when constructing roof support to allow for the weight of the metal. If you need help installing metal roofing read my article How to Install Metal Roofing On a Shed.
Pros and Cons of Using Metal Roofing
Pros: Metal roofs usually last a long time, sometimes up to 70 years. However, this depends on how thick the metal is that was used and what kind of coating was applied to the material. Metal roofs help keep the shed cooler in summer, as the metal reflects heat. These roofs can handle a lot of abuse from sun, wind and rain.
They are generally very wind-resistant if they are attached firmly to a strong building. They are very fire resistant. Burning embers landing on the roof won’t hurt anything. The roofing is entirely recyclable, and most metal roofing materials available today are at least partially made with recycled metal. Some roofing material comes in many colors, with more options added over time.
Cons: Any metal roofing material can be dented by large hail or tree debris, although some materials and thicknesses are less prone to this than others. Some materials, such as steel, can rust under certain conditions, such as being subjected to salt in the air or if the protective coating is scratched off. Metal roofs can be noisy in hail or even heavy rain.
However, the roof sheathing should dampen some of the noise, and wood framing under the metal can improve this even more. Metal roofs are also prone to something called oil canning, which is a sort of rippled appearance.
While this is caused by the natural expansion and contraction of the metal due to temperature and won’t hurt the roof or cause leakage, it is bothersome to some people. Repairs are also more expensive also. Instead of replacing a few shingles, any repair to a metal roof means replacing a full panel.
Does a Metal Roof Lower Your Insurance?
Metal roofing on your shed is not likely to affect your insurance rates. Most homeowners’ insurance policies insure outbuildings as part of the policy. They usually insure these buildings at 10% of the coverage for your home. This doesn’t include the contents of the shed.
Can I Put a Metal Roof Over Shingles?
You can install a metal roof over shingles, providing that your building codes allow for this. Many building codes limit the number of layers of roofing that can be installed. Shingles can provide insulation and a good sound barrier under the metal roofing. They also provide added moisture protection.
However, a metal roof should not be installed over shingles that are not in good shape and should not be used to cover up a shingle roof that needs to be replaced because it is in bad condition. This is especially true if there’s a chance that damaged shingles may have let in moisture, damaging your roof sheathing. Covering up something like this can only lead to further problems. Check out my article How to Install a Skylight in a Shed if you need more light in your shed.
What is the Easiest Way to Cut Metal Roofing?
Using tin snips or shears is the easiest way to cut the roofing material by hand. They come in different forms for cutting straight or curved lines. There are also power shears available to make the job easier and faster. If you want to use a circular saw for long lengths, use a blade made for metal cutting and get a few, as they do wear out rather quickly.
A carbide-toothed blade costs more but will last longer. You’ll also need eye and ear protection. Cutting metal with a saw is very loud. Also, be sure to cut your metal in a place away from your stack of material. Sawing the metal creates hot metal sparks while can burn through the protective coating and paint if they land on some of your other roofing panels.
Does a Metal Roof Affect Cell Phone Reception?
No, metal roofing doesn’t affect cell phone reception, either in a home or outbuilding. Many business buildings have metal roofs or metal parts on the roof or in the walls. None of it affects cell phone reception.
What is Ribbed Metal Roofing?
Ribbed metal roofing is just what you’d expect. It is formed to have raised ribs that slope down the sides. This ribbing acts much like the ribs in corrugated cardboard, adding strength to the panels and preventing bending. The raised ribs are usually flat at the top, with straight valleys in between the ribs.
These have variations in form, such as a taller rib followed by two or three shorter ribs. These profiles are divided into two main types: 5V-Crimp panels and R-panels. The 5V-Crimp panels look almost just like the more expensive standing seam panels. The main difference is that the fasteners on the standing seam roof are hidden, while they are exposed for the 5V-Crimp panels. The R-panels come with quite a bit of variation in the ribs.
Some of the types of ribbed metal profiles include:
7.2 Structural Box Rib. These panels are constructed with an anti-siphon groove to help protect against leakage. It’s not only used for roofing but for siding as well. Since it uses exposed fasteners, it’s fairly easy to install.
Purlin Bearing Rib. Called PBR panel for short, it’s one of the strongest panels using exposed fasteners that can be purchased. It also has an anti-siphon groove built-in, making it good for roofing. It can stand up to almost any type of climate.
Delta Rib. This panel is very tough, having been designed originally for agricultural settings. It is now popular for use in roofing homes.
Tuff Rib. Another panel profile first designed for the agricultural market, this type of panel is also fine for roofing and siding. It will withstand rain, hail, snow and rain.
Whatever the form or profile of the ribbing, the panels are made with a rib at each side in order to overlap the next panel. Screws attach the two panels at the overlap and are driven down into the roof support.
Ribbed metal panels are generally less expensive than standard seam roofing, not only because the fastening system is exposed but because they are generally offered in less thick gauges. The smaller the gauge number, the thicker the metal. Standing seam roofing usually comes in gauges as thick as 22 gauge, while ribbed metal is usually only offered in 24 or 26 gauge.
Because its fasteners are exposed, the panels are usually caulked at the joints and this caulking must be regularly inspected. The fasteners as well should be inspected, as the natural expansion and contraction of the metal panels may cause them to loosen eventually.
What’s the Difference Between Corrugated and Ribbed Metal Roofing?
Both types of roofing are formed with essentially the same process and their costs are similar. Corrugated roofing has alternating hills and valleys formed by ridged rollers during the milling process. The roof is formed from interlocking metal sheets. The hills and valleys are the same widths.
Ribbed metal roofing has hills also, which may be flattened at the top, and has a flat space in between the ribs. Some have variations in spacing or rib formation. It is formed into panels that run the length of the roof slope. Most people use the ribbed panels on their homes, as the corrugated roofing is considered to look less modern and more utilitarian. The ribbed panels look more like standing seam roofing, which is more expensive.
While metal roofing with exposed fasteners means that fasteners must be inspected for loosening periodically, it is the easiest type to install and the most popular for sheds. You probably won’t opt for very expensive material, so your choice will be between aluminum and steel. Whatever your choice, your metal roof will serve you for the lifetime of your shed. If your not sold on metal roofing read my article How to Choose the Best Roofing Material for a Shed for other roofing options.