Metal roofs are growing in popularity, with approximately 750,000 metal roofs having been installed on residential buildings in 2015.
This number has increased substantially over the last few years. When it comes to metal roofs, you might think of using materials such as steel or aluminum, but zinc is also a viable option.
Why should you consider a zinc roof?
A zinc roof has many advantages, such as being eco-friendly and beautiful. It comes in a variety of shapes, while being highly durable.
If you’d like a different roof for your home, you should consider one that’s made out of zinc. Read on to learn everything you need to know about zinc roofs.
Zinc Roofs: What Are Their Pros And Cons?
If you’re interested in metal roofs, you might not know that zinc is one of the most common types of metal you can use for your roof. Zinc is quite a popular material for roofing materials – in Europe, for example, 70 percent of all residential roofs contain zinc metal panels. There are good reasons for this, which we’ll see in our rundown of zinc roof’s pros and cons.
Zinc Roof Advantages
Zinc has a long lifespan
When you install a zinc roof on your house, it can last for between 80 and 100 years. This is thanks to how zinc is resistant to fungi, mold, mildew, fire, and insects.
Zinc develops a patina over time
Over time, zinc experiences an oxidation process called a patina. This is basically a protective layer that forms on the surface of the zinc. If it happens that something scratches the zinc, the patina reforms itself. This patina also causes the zinc to change color over time. It looks dark-grey to almost black at first, then it lightens to a pale grey or blue.
Zinc is eco-friendly
Thanks to how zinc is recyclable, you can reuse it again and again, which means that it’s an eco-friendly material.
Zinc comes in different styles
You can find zinc in a variety of colors and finishes to suit your needs. You can even find zinc roofs that have been pre-pigmented, so you can find them in a variety of colors, such as purple, red, and orange.
Zinc is malleable
Since it’s a thin metal, zinc can be shaped and formed according to the owner’s preferences, which makes it ideal for curves in your home design.
Zinc Roof Disadvantages
Although there are many good reasons to install a zinc roof in your home, there are some potential drawbacks that you should consider.
Zinc is expensive to install
A square foot of zinc can cost roughly between $5 to $8 per square foot, and the labour for installing a zinc roof can cost between $10 and $20 per square foot.
Zinc’s patina is variable
Some people are wary about the patina that forms on zinc. This is because there’s no guarantee of what color the patina will be and there could also be inconsistencies with the patina and how it forms throughout the zinc panels.
Zinc requires the right pitch
Zinc roofs need a minimum fall of three degrees. This gradient basically means that a fall of just over 50mm is required in every meter to create a slope. The risk of this low-pitched roof is that water can build up where seams overlap. While seam-sealing tape on the joints can help to reduce this problem, it won’t entirely eliminate the risk of water penetration.
Zinc isn’t suitable for coastal environments
If you live in close proximity to the sea, you could find that your zinc roof becomes corroded or stained as a result of the sea salt in the air. This can cause the zinc roof to become damaged, reducing its lifespan.
How Much Does It Cost To Install A Zinc Roof?
Zinc is easy to install because it comes in pre-formed panels and sheets that you can use to cover large areas of your roof quickly.
Zinc costs between $4.50 to $8.50 per square foot. This means that it can cost between $450 and $850 for 100 square feet of the material.
The cost of your zinc roof is influenced by what type of roof you have. This includes a standing seam or tiles/shingles. You can expect to pay between $6 and $8.50 for standing seam metal roofs, whereas it will cost you between $4.50 to $6.50 for zinc tiles or shingles.
Extra costs for installing a zinc roof include flashing, underlayment, and fasteners. These will cost approximately $1 per square foot. But, the cost for the entire zinc roofing installation costs between $12 and $18 per square foot, and this will include costs for labour and materials.
Should You Choose Zinc Over Other Metal Roofing Materials?
If you want a metal roof, you might wonder if you should choose zinc or other metals, such as aluminum or steel. Let’s explore and compare their features according to different categories.
Durability and Strength
Roofs made of steel, zinc, and aluminum are all durable. However, zinc has a bit of an edge over the other metals because it’s self-healing. This means that it will be easier to maintain. If zinc gets scratched, it will recover by itself over time. By comparison, types of steel roofing materials, such as galvalume, are not self-healing.
That said, steel roofs undergo manufacturing techniques, such as coatings, that make them score higher points for longevity.
Ease of Installation
Zinc installation can be a bit more complex than other metals and it requires an experienced roofing contractor. This is why it can be a bit more expensive than aluminum and steel roofing materials.
In addition, because steel roofing comes in a variety of color options, you can replicate the appearance of aluminum and zinc at a lower cost.
Zinc wins in this category! It’s eco-friendly because it uses a lower melting point during its production. This means that less energy is used to make it.
That said, both aluminum and steel can be recycled at the end of their lifespan.
Tips For Maintaining Your Zinc Roof
Once your zinc roof has been installed, it’s important to ensure that you look after it to keep it in excellent condition. Here’s what you need to know.
You should check the roof regularly for any debris, such as grass and leaves, and remove them.
Check the gutters so that they’re not blocking the flow of water.
If you need to wash your zinc roof, you can use a solution of water and mild detergent. Make sure you clean your roof in the direction of the metal grain.
Complete washing your zinc roof by applying a small amount of mineral oil to it. However, test this oil on a small area of the zinc roof before you apply it all over.
How To Repair A Leak In Your Zinc Roof
If your metal roof has a leak in it, you should fix it to prevent water damage. You can do this yourself. These tips can also help you if you have a different kind of metal roof.
Start by finding the source of the leak
An extension ladder is required here for you to access your zinc roof. You might find punctured holes, which are a dead giveaway for leaks. You should scrutinize the seams that connect the metal panels. If there are any cracks or gaps on the seams, these will be suspicious for leaks. While you’re up there, check the metal roof for any loose screws.
Repair the screws
If loose nails are the problem, replace them. A rusty nail can be removed with a nail bar. If it’s difficult to remove rusty screws, make a screw hole with a cordless drill and screw drill bit. Then you can drive a one-inch galvanized-steel screw to secure the metal. This will also prevent future rusting from occurring.
Seal up gaps
Clean away any debris from the metal panels and then apply a base coat to prevent water from being able to penetrate the gap. Cut sheet metal to the size you require for the gap you have to patch. This should overlap the metal panel by around two or more inches so it goes past the edges of the hole. You should round the corners of your patch with an emery cloth or file to prevent sharp corners.
When you have measured the patch, place it over the gap and outline the patch with a pencil onto the roofing. Then you can remove the patch and check to ensure that the patch will overlap the hole by two inches.
Now you can go ahead and apply the patch. Apply urethane sealant to the surface, making sure that it matches the color of the metal panel. Press the patch in place over the hole.
Once you’ve done that, you can attach the patch to the surface with some metal screws. Make sure you put screws every three or four inches all around the patch’s perimeter. Make sure that you use screws which are long enough to effectively fasten the patch to the metal panel. You should never use screws that are too long, though, as these can enter the rafters or roof decking.
You can paint the patch so that it perfectly matches the roof.
How Long Does Zinc Roof Patina Take To Develop?
All zinc eventually gets a patina, but there’s no clear rule about when you can expect this to happen to your zinc roof. It can happen within a few years or within 30 years, so you’ll have to wait and see.
However, the climate in which you live will affect how long it takes for the patina to develop. If you live in a hot, humid, and damp region, the patina is likely to develop at a faster rate than if you live in an area that isn’t affected by these conditions.
Is A Zinc Roof’s Patina A Good Thing?
While you might be worried about a zinc roof’s patina and how it will discolor your roof, a patina is something that develops in the roof to protect it against damage, such as in the form of corrosion and rust. This increases its durability, so a patina is essentially a good thing.
Why is your zinc roof turning chalky white?
This tends to happen as a result of moisture, humidity, and a lack of proper ventilation in your roof. If your roof has been properly installed, with the zinc being coated and the roof being well ventilated, it will prevent this issue from occurring.
Do other types of metal roofs develop a patina?
It’s not just zinc roofs that develop a patina. This discoloration can also occur with other metal roofs, such as steel and copper.
If you’re interested in installing a zinc roof on your home, you might wonder if it’s a good idea. While a bit unconventional, zinc roofs are popular for many good reasons.
In this article, we’ve provided you with everything you need to know about installing zinc roofs, such as their advantages and disadvantages, so you can see if a zinc roof is a good choice for your home.
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.