Roofs, even traditional ones, can withstand simple precipitation. But what happens when an updraft carries the water droplets well into freezing heights, forming hail? Can your roof withstand the pressure of ice balls falling at high speed, sometimes the size of golf balls?
When hail happens, you need extra protection. Metal is the best choice for your roofing needs, but what kind of metal is the best when it comes to hail? We’ll explore the different metals used in roofing (aluminum, zinc, copper, and steel) so you can make the right decision choosing your roof.
Types of Metal
Aluminum has been a choice selection of roofing material in the United States for well over a hundred years. The first architectural aluminum roofing installed was on top of the Washington Monument in 1885.
If you think about any regular aluminum can, you can apply its same characteristics to aluminum roofing; in fact, most of the makeup of aluminum roofing is through the recycling of aluminum cans (about 90%-95%). If you’re concerned with reducing your home’s carbon footprint, aluminum roofing is a great place to start.
The average thickness on aluminum roofing will be approximately 0.019”, meaning it will be thicker than a regular aluminum can. In fact, a square of aluminum roofing can use a little over a thousand aluminum cans through the power of recycling. It can also be thicker, as well, at a minimum of 0.032” for a “standing seam” style.
● Can come in almost any color
● Lightweight material, making it easy to move and install (about 45 lbs. per square)
● Rust free, no unsightly rust stains on your roof, making your home more visually pleasing
● Energy efficient, lowering your monthly heating and cooling bill
● Highly malleable
● Higher price than steel
● Not particularly hail resistant, especially in lower-thickness style profiles
Copper is the most beautiful option because of its distinctive hue and potential to, over time, go from a striking metallic red color to an attractive bluish-green color from oxidation. This process is “patination.” The length of time patination takes depends largely on the atmosphere (i.e., for a roof in a coastal area, the process would take less time).
You often see copper on historic buildings and churches. Today, it is hard to find copper as an installation on the whole roof of a residential dwelling due to its cost. However, if applied to “accents” (for example, over bay windows), it can add a spot of sophistication to any home.
● Very visually attractive and the elements make it even more beautiful
● Easily worked with/installed/easy to solder
● Lasts a long time
● Highly durable, with a thickness range from 0.016” – 0.022” for pre-formed shingles (depending on weight) and 0.022” – 0.027” for vertical seam (depending on weight)
● Very costly
● Runoff of rain will stain other materials used on the home
● Patination, unless achieved through pre-patinated panels, can take a long time
● Though highly durable, hail can still dent copper roofing
Zinc is very similar to copper. It achieves a patina over time and can last for 100 years or more. Unlike copper, zinc has a chalking effect, which turns a greyish-blue color over time and can become somewhat unattractive. The good news about the patina of zinc is the ability to clean it, making it a controllable issue in the long run.
What zinc lacks in attractiveness, it makes up for in its ability to heal itself of scratches with its patina, which means it is the only roofing with a superpower.
You will most likely see zinc on commercial buildings as opposed to residential homes, the reason being it is easy to form into a variety of shapes, making it multi-purpose for all sorts of projects.
What is particularly impressive about zinc roofing, aside from its power of self-healing, is its environmental friendliness. Zinc, of all the metals available for roofing, is the “greenest” or most environmentally sound option. Why is that? It has the lowest melting point of all metal roofing options. Since it is easier to melt, it is easier to process and therefore uses only 25% of the energy it takes to make steel or copper.
● Environmentally friendly to produce
● 100% recyclable
● You can clean patina
● Self-healing and can last for hundreds of years
● Expensive, on par with copper
● Chalking effect can stain other surfaces where water flows, which is unattractive
● Can damage easily by hail or high winds (depending on the panel/shingle design)
Steel is a metal alloy, which means it is not a pure substance. It is a combination of iron and other elements. You can see steel everywhere from commercial construction sites to residential homes. It is an extremely popular option on the market today.
Steel is available in three (primary) types:
● Galvanized. Galvanization is a layer of zinc protecting the inner layer of steel against corrosion. This process of coating lengthens the overall life of the steel. It is the most commonly found steel roof material.
● Galvalume. This type of steel is almost the same as galvanized except for one difference: instead of just zinc, it uses both aluminum and zinc combined. It has the advantage of being less corrosive than galvanized steel but is more susceptible to scratches or cut edges.
● Weathering steel. This type of steel is primarily for heavier projects such as bridges. As the name suggests, its ability to weather over time is high so people generally buy it with the knowledge that it will rust and therefore resist the need for regular maintenance.
● Low cost
● Able to mimic copper, zinc or other higher-priced roofing options by painting it to match the patina
● Varied use, suitable for a variety of projects
● Easily accessible
● Highly recyclable, does not have the energy production rating of zinc, but manufacturers make most steel from recycled material
● Works extremely well in hail and high winds, the most preferred for hail or high wind
● Can rust (you can prevent this with treatments, however)
When it comes to hail, the best and most effective option for metal roofing will always be steel. It has long been the go-to for residential and commercial roofing contractors. Choose a metal roof for optimal protection from inclement weather conditions.