Making mistakes during metal roof installation can be costly. That is why you need to hire experienced contractors to handle the task on your behalf. However, even seasoned contractors can make mistakes. Therefore, you should always check with them to ensure they get it right.
Below, we offer tips to help you get everything right. The goal is to avoid problems and risks that could lead to losses and disappointments.
Table of Contents
- Ensure That Your Contractor Has Relevant Training and Experience
- They Must Choose the Right Metal Panels
- Be Keen on the Equipment They Will Be Using for Roll Forming
- Ask How the Contractor Intends to Deal With Oil Canning
- What About Thermal Movement?
- Other Questions to Ask
Ensure That Your Contractor Has Relevant Training and Experience
Before anything else, you must be sure that the contractor is qualified to handle the task. Contractors with certification and training will handle metal roof installation better. However, the nature of training also matters.
Some training programs only provide theory-teaching classes, where trainees sit through a two-hour power-point presentation. Others will incorporate at least two days of “hands-on” training, where the trainees get to install panels. Obviously, you should pick hands-on certification programs over theory-type certification.
Moreover, you should require the installers to have at least five years of experience working on projects of the same magnitude. It should not be the first time they are handling such a project considering the complexities involved in installing a metal roof. They should provide a list of references from former clients to this effect.
They Must Choose the Right Metal Panels
You should ensure the installer picks the best panels for the project during the design phase. Metal panels are not equal. They vary in quality and performance depending on the type of material, the metal substrate, and paint systems.
Metal Roofing Materials
There are several metal roofing materials from which to choose. What metal your manufacturer chooses will depend on weather conditions in your area. However, your choice here will mostly depend on your budget.
Steel is the most common metal roofing material. Made by combining iron and other elements, the alloy is popular in both commercial and residential applications.
Steel is cheaper than other metal materials, but it is durable and requires minimal maintenance. Its drawbacks include lower corrosion resistance and greater weight compared to other metals. Buying a standing seam steel panel will cost between $2 and $4 per square foot.
Aluminum is the lightest metal roofing material you will ever come across. It is a common choice in architectural applications.
The metal is preferred for its high corrosion resistance—it does not rust. As a result, it is the metal roofing material of choice for coastal environments, where sea salt water is prevalent.
Disadvantages of aluminum include high cost, less availability, and high susceptibility to denting. A standing seam aluminum roofing will cost between$4 and $6 per square foot.
Copper is known for its beautiful appearance. Over time, the material develops a brown or blue-greenish patina depending on the environment. Other than improving the appearance of a roof, the patina also makes the surface rust-resistant.
Copper roofing can last up to 100 years or longer and will outlast other metal options. However, its high cost (only comparable to zinc) makes it a less popular roofing option. A standing seam copper roofing will cost anywhere between $9 and $12 per square foot.
Tin roofing is virtually obsolete. Whenever you hear the term, it is often referring to steel coated with tin. The coating enhances the roof's durability.
Zinc is similar to copper in many ways. It will also develop a striking patina over time and can also last for more than 100 years. It also attracts very high prices, which explains its unpopularity in the United States. For a standing seam zinc roofing, you will pay $12 to $14 per square foot.
The most common steel substrates are Galvanized and Galvalume. Galvanized steel includes a zinc coating that makes the panel corrosion resistant. The amount of coating is measured by a G-rating. The more zinc applied, the higher the G-rating.
Galvalume coating consists of an alloy of zinc plus aluminum. Compared to Galvanized, it offers superior performance and can extend the life of your metal roof for 50 years or more. It also comes with warranties against rupture or perforation caused by rusting. The same does not exist for Galvanized.
Choosing the best paint system is just as essential. There are three options on the table. PVDF, polyester paint, and silicone modified polyester. The coatings are supposed to shield the panels from harmful UV rays, which can cause fading and chalking.
Polyester paint is the least expensive option, but it also offers the least protection against UV rays. Therefore, it is unsuitable for residential applications. Of course, you can install it in basic shelter projects, where performance is not crucial.
Silicone-modified polyester performs relatively better but is prone to fractures due to its hardness. PVDF, also known as Kynar 500, is the best paint coating and will offer superior protection against harmful UV rays. However, it is the most expensive option.
A conversation with your contractor is necessary before deciding what metal substrate or paint system to choose. Budget considerations and the type of application will guide your choice.
If you are roofing a residential house, you want panels with the best of both. However, cheaper options will make more sense for sheds, barns, or other basic shelters.
Be Keen on the Equipment They Will Be Using for Roll Forming
If the installer intends to roll-form the panels on-site, always confirm the expertise of the personnel on-site and the equipment they will be using. While looking to cut costs, contractors could rely on maintenance-starved equipment, which could only produce substandard panels.
Installing panels that don't meet the manufacturer's specifications could result in performance issues and problems such as oil canning. In the worst-case scenario, it could even result in a total system failure.
Ask How the Contractor Intends to Deal With Oil Canning
Oil canning is an inherent problem in roofing that occurs in all types of metals. It makes the metal panels appear wavy and distorted, especially in the flat areas. Although it does not affect the structural integrity, the phenomenon can diminish the aesthetic appeal of your roof.
Therefore, it is an issue that you need to talk about with your contractor.
It is hard to pinpoint the root cause of oil canning in the majority of cases. However, your installer can take specific precautions to reduce the risk. These include proper handling and storage of the panels to avoid twisting or stressing the material and installing screws and clips per the recommended specifications.
You can also talk to the installers about breaking up the flat surface with stiffening ribs and striations during roll forming. It may not cure oil canning, but it will reduce the area of the flat surface. That will make the phenomena less prevalent.
Installing metal panels on an uneven deck is one of the most common causes of oil canning. Therefore, ensure the installer is satisfied with the condition of the deck before they commence installation. If the plane on your deck is inconsistent, consider leveling it first beforehand.
What About Thermal Movement?
Metal is bound to expand and contract with temperature fluctuations. If your roof installer does not accommodate this movement during installation, problems will occur. One key consideration to make is the type of clips they use.
Clips in standing seam systems allow for thermal movement apart from improving the aesthetics. Your contractor has two main options: fixed clips or sliding clips. Both allow room for expansion and contraction but at varying degrees.
The former depends on the deck's ability to expand and contract together with the roof system. Therefore, it allows lesser movement. But although sliding clips still secure the panels to the substrate, the panel movement is not dependent on the deck. Instead, they allow the panels to move within the clip, leaving more room for thermal movement.
Where the installer chooses to pin the panels also determines the direction of movement. Essentially, you only pin one end while the other is left to float.
In most cases, the installer will pin the eave and leave the other end hanging. However, they can also fix the ridge, leaving the eave to float. Furthermore, they can also pin the panels at the center for maximum thermal movement in long panel runs.
Other Questions to Ask
Asking the right questions can make the difference between a long-lasting roof and a problematic one. The following are a few other questions that your contractor should answer before they commence the project.
Do You Intend to Lap the Panels?
The conversation around lapping is crucial because of the risks involved. Lapping is not inherently faulty, but installers have a higher risk of making mistakes during installation. A favorable alternative is roll-forming single-piece panels. Contractors can roll-form lengths of up to 250 inches on site.
If lapping is unavoidable, however, ensure the installer follows the manufacturer's specifications. Also, ensure the laps are as staggered as possible to minimize the possibility of making errors that can be costly in the future.
Do You Anticipate Repairs or Remodeling in the Future?
If you live in a region that experiences extreme weather conditions, chances are your roof will require repairs sometime in the future. That will be almost impossible if the system does not allow for individual panel replacement. The alternative would be to tear down the whole roof, which would be an unnecessary and costly undertaking.
Your installer can either use the T-style system or the traditional vertical leg system. The former incorporates separate seam caps. That means you can replace damaged panels without tearing down the entire system.
On the other hand, traditional vertical legs systems have batten caps joined with the panels. Therefore, it is nearly impossible to make any repairs without affecting the entire roofing system.
Standing seam roofing systems are supposed to last for many years. As a result, the issue of repairs and replacements may not be pertinent to many homeowners. But if your area experiences heavy snow or ravaging storms, this is a conversation you need to have with your contractor.
How Do You Intend to Deal With Snow?
If you reside in a Snow Belt region, snow can cause problems for your roof. Fortunately, the snow will slide off faster in metal roofing than in other roofing materials, so you don't have to worry much about heating bills. However, you still have to consider where the snow is sliding off to.
If the snow is falling around your house and blocking your entrances and sidewalks, you have a serious safety issue on your hands. That's why it is essential to talk to your contractor about installing a snow fence or snow retention on your roof.
How Will You Deal With Dissimilar Materials?
Is the Contractor using dissimilar materials on your metal roof? The move can be disastrous to the panels. When both metals get wet, the run-off from one could cause the other to corrode. The same problem could occur when you install products containing metals such as lead or copper on the roof. These could include air conditioners or pipes.
If it is not possible to use one type of material throughout, ensure your contractor takes measures to separate them. They can achieve this using a sheet barrier. Also, they should make sure the metals never get wet to avoid direct contact through run-offs.
Manufacturers are prone to making mistakes, especially with highly technical installations such as standing seam metal systems. Therefore, it is upon you to constantly check to ensure they follow the manufacturer's recommendations.
To do this, you need to know what to look out for. You can use the tips outlined above to learn how to ask the right questions. Keeping your contractors on toes will help avoid problems and mitigate risks during the installation process.