When thinking about updating your old roof, it’s common to consider installing a metal roof over shingles. However, is it possible? Today, we’ll answer this question. Additionally, we’ll show you which are the main types of metal roofing. Lastly, we’ll go over some main considerations when going for this installation.

What are the Main Types of Metal Roofing to Choose From?

So, is installing a metal roof over shingles possible? Long story short, you can proceed with this installation. In fact, if you do so, you’ll keep down labor costs and save time. Not only that, but you’ll also minimize any unnecessary roofing waste ending up in landfills.

Because metal roofing has a long life expectancy, it tends to be a top option for homeowners. Not only that, but its low weight also allows you to have a unique design that’ll reflect heat while at the same time being cost-effective.

Moreover, if you wish to be completely sure that you can install this roofing material over an asphalt roof, then check with your local building department. By doing so, you’ll be able to find if your state allows re-roofing.

Additionally, keep in mind that some states don’t allow homes to have more than two layers of roofing.

Methods on Installing a Metal Roof Over Shingles 

Of course, since installing a roof over your previous one is a re-roofing project, you need to be aware that it’ll require a different process compared to a replacement or installing a new metal roof from scratch.

Unlike a normal metal roof installation, there are three main methods for you to contemplate, each having its pros and cons.

The first method consists of removing the shingles before installing the roof. That way, the roofing contractor is able to see if you count on any rotten plywood.

Some pros of this installation method include the overall inspection of your roof’s condition and removing old plywood. However, it is often more expensive due to the additional labor and time needed.

We then have the installation of underlayment over the shingles before placing types of metal roofing. The underlayment helps prevent the shingles from scraping the new roof. This is the fastest technique for this type of project. Additionally, it’s the one requiring the least labor.

Nevertheless, a big drawback this method brings is the fact that you won’t be able to replace any rotten pieces your roof might have. Also, it won’t provide a flat surface for the metal roof to attach to.

Lastly, we have the installation of 1×4 purlins over an asphalt shingle roof before placing a metal roof. This technique tends to be the most common option for homeowners. Yet, you’ll need to make sure that the plywood is in good condition.

One main benefit regarding this method is the ability to add an extra insulation layer. Furthermore, the metal roof will have a flat, solid surface to attach to. Lastly, there will be an air gap that will allow airflow between the layers.

Remember that a proper roof inspection is vital if you wish to make sure that there’s no rotten plywood.

What to Consider When Installing the Different Types of Metal Roofing

Homeowners must be aware of some key factors when re-roofing their homes. That’s why we’ll mention which are the main considerations to keep in mind.

These are three main things to consider when going for a re-roof:

• It’ll be harder to detect leaks
• You won’t replace some old materials
• This installation type will cover your roof’s framing

It’ll Be Harder to Detect Leaks

If you’re already experiencing leaks with your previous roof, then remember that a metal roof won’t solve your problem. So, if you ever get a leak on your metal roof, it’s probably that the water will make its way to the previous leak. In other words, you won’t be able to use your common techniques on finding water damage in a metal roof.

You Won’t Replace Some Old Materials

Re-roofing often bypasses the tear-off process. Because of this, you won’t be able to replace any crucial materials such as the underlayment.

This Project Will Cover Your Roof’s Framing, No Matter the Type of Metal Roofing

Depending on the installation method you’re going for, there’s a chance that you won’t be able to know your decking’s integrity. If this scenario happens, then you might end up having a much costlier problem in the future.

So, you should ask your contractor to make a thorough inspection. You can also take the initiative by downloading our simple yet effective roof check-up checklist.

When Should You Consider a Complete Roof Replacement?

So, when is it time to completely replace your roof?

Although re-roofing your roof is a faster and less expensive way to restore your roof’s appearance, it might not always be a good idea. As we said before, there are many considerations to keep in mind.

Here are some cons a reroofing project might bring compared to complete roof replacements:

• You can’t re-roof an existing metal roof.
• Re-roofing doesn’t last as long as complete roof replacements.
• This type of project doesn’t fix significant roofing issues.

So, long story short, if you see any red flags regarding your roof’s condition, then go for a complete roof replacement.

Although a replacement project might be costlier, the rewards it grants to homeowners often make this decision worth it.

For instance, you’ll be able to reap the benefits these types of metal roofing provide, such as a lifespan of 50 years and its energy efficiency elements. Moreover, you won’t need to worry about any rotting or sagging of your roof. Lastly, you’ll be able to remove any existing water damage. Now that you know that installing a metal roof over shingles is possible, along with the primary considerations for this project, it’s time for you to take action!

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