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How to Install Metal Roofing over Shingles Right

For many years, shingle roofs have been the best option for residential homes. Nevertheless, in our time, metal roofs are gaining more and more popularity. This is due to their reliability, quality, and durability.

When you decide to install a new metal roof, you can do it in two ways. The first way is to dismantle the old roof, and the second is to install a metal roof over shingles.

The installation of a metal roof over shingles can be done in three ways. The installation can be influenced by many factors, the condition of the existing roof, the weather conditions in the region, and additional elements. Before installation, it is necessary to inspect the roof deck to determine if it is possible to install a metal roof over shingles.

Can you put a metal roof over shingles or not will become clear after inspecting the existing roof. Based on the information received, a professional metal roof installation team will give you a detailed answer on how to install metal roof over shingles in your particular case.

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How to Install Metal Roofing over Shingles

When you are planning to install a new roof, it is better to entrust this business to professionals. It is especially important to adhere to this judgment when you do not know how to install metal roofing over shingles. There are three installation methods for this case:

    1. Metal Directly over the Shingle with a Layer of Underlayment
    2. Installation with Fanfold Insulation
    3. Installing a Metal Roof on Wooden Planks

These methods of installing metal roofing over shingles are very similar, but they can also differ depending on the condition of the existing roof, roof pitch, weather conditions, and other individual characteristics.

For a quality installation, all possible details must be taken into account. That is why you will need the help of a professional metal roof contractor.

Metal Directly over the Shingle with a Layer of Underlayment

Often the question arises: can you put a metal roof over shingles without intermediate layers. If you just answer it, then yes, there is such a method of installation. However, it is recommended to install a layer of underlayment before installing a metal roof.

This thin layer is designed to protect the metal coating. Shingle roofs are covered with sharp granules on top, and this barrier prevents the protective layer of the metal roof from scratching.

If you install of metal roof over shingles without this layer, you risk ruining the metal roof. This can lead to a decrease in its lifespan and the need for repairs after several years.

Installation with Fanfold Insulation

The second method of installing metal roofs over shingles is using an insulating layer. The main task of this layer is to protect the asphalt roof, which will be located under the metal, from overheating.

Since the asphalt roof will be under the metal roof, it won’t be able to cool down as quickly when the sun goes down. This can lead to overheating of the home, which can cause many inconveniences. In addition, high temperatures can cause the asphalt roof composition to melt and deform.

To avoid these problems, quarter-inch insulation is used. In addition, this layer also helps in the process of installing a metal roof. It prevents the appearance of dents in the attachment points of the new metal roof.

Installing a Metal Roof on Wooden Planks

In climates with frequently changing temperatures, moisture can form between the layers of the roof. And how to install metal roofing over shingles to prevent condensation? To do this, you need to create an air cushion between the two layers of the roof.

This air cushion is created when wooden planks are used before installing a new metal roof. These quarter-inch wooden planks are installed directly on the asphalt roof, and a metal roof is already attached to them.

This installation method is very common because it avoids several problems at once. First, you reduce the chance of dents and bends in the metal roof. Secondly, the correct installation of the planks allows you to create an open-air space between the two roofs and will not allow moisture to accumulate.

For such a roof to function correctly, the wooden planks must be installed parallel to each other. If some of them are vertical, and the other part is horizontal, then in some places closed air pockets will form. This will disrupt the natural circulation of air and condensation will form.

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Why do People want to Install Metal Roof over Shingles

As you understand, such a feature as the installation of metal roof over shingles has its merits, otherwise, this method would not make sense. When planning this type of metal roof installation, people can get some advantages, which include:

Undoubtedly, each of us would like to renovate our home as cheaply as possible, if this does not affect the quality. By installing a metal roof over shingles, you can save on several processes at once.

Firstly, since there is no need to remove the existing roof, then you save on dismantling work. The second thing to note is that shingles are not a recyclable material. Therefore, you will have to pay a certain amount for the disposal of such a roof.

This installation method can significantly reduce the cost of a new metal roof. For example, 2000 sq. ft. metal roof you can spend $1500 – $2000 less than if you were dismantling an existing shingle roof.

The question can you put a metal roof over shingles can also arise when the timing of the installation of a new roof is very important. In the case of this installation method, you avoid several processes associated with the dismantling and disposal of a large amount of garbage.

If the homeowner needs to install a new metal roof as soon as possible for whatever reason, over shingles can be an excellent solution to the problem.

Also, the speed of roof installation is influenced by which of the three ways it will be performed. But it is worth noting that the method of installing a new metal roof over shingles depends on the characteristics of the roof, and not on the speed of installation.

Another positive point is that when you install metal roofing over shingles, the old roof can serve as an additional protective layer. If the shingle roof is in good condition, then it will be an additional protective barrier against moisture penetration.

An additional layer of the roof will also serve to isolate noise. Modern metal roofs are not very noisy in the rain, but it is not worth excluding the possibility of increasing the insulation.

These advantages can only be obtained if the metal roof is installed correctly, taking all factors into account. Monarchy Roofing has been manufacturing complex metal roof installations for many years and has tremendous experience in this field. Our experts will be happy to help you and carry out the installation of a new metal roof.

What Kind of Metal Roof over Shingles Problems can Be?

It is also worth mentioning what metal roof over shingles problems can arise. After all, when you install a metal roof in this way, you are adding another layer of the roof. In this case, some problems may arise that should be taken into account before you decide to install metal roofing over shingles.

The second of the metal roof over shingles problems is the creation of dents when installing fasteners for the future metal roof. Since the material of an asphalt roof is quite soft, dents and depressions can occur when you attach metal roof brackets to it.

The method of installing a metal roof over shingle only with a layer of underlayment is especially susceptible to this kind of problem. When the mounts are not aligned, bends and dents can occur in metal panels. If the level difference is small, then these bends will be hardly noticeable, especially on dark metal panels.

However, the bending of metal panels is not considered normal during installation. This is because additional pressure is exerted on the metal in the place of the bend, which can eventually lead to damage to the roof.

There are a couple of ways to minimize this kind of problem when installing metal roof over shingles. To prevent the asphalt roofing from sagging, use installation methods with an intermediate insulating layer or with wooden slats.

Also, in order not to form bends, it is better to use corrugated metal roof panels. This type of metal roof is less susceptible to bending than perfectly flat panels in standing seam metal roofs.

The metal roof brackets used can also play a role in reducing the chance of dents occurring. snap look mounts are more flexible than mechanical look and are better suited for installing metal roofing over shingles.

We have already mentioned above that improper installation of metal roof over shingles can lead to the formation of moisture between two roofs. Nevertheless, it is worth discussing this problem in detail. Water is very destructive for many roofs, in particular for metal ones.

If moisture gets on the plywood, it can destroy it pretty quickly. There may also be problems with the roof covering itself. Where there is damage to the protective polymer layer, corrosion can form on the metal roof.

Also, high humidity contributes to the development of moisture. Organisms such as moss and mold not only spoil the aesthetic appearance but can also destroy the layers of the roof.

So how to install metal roofing over shingles to keep moisture out? As we have already mentioned, it is necessary to leave free space for air movement between both roofs. This will prevent moisture accumulation and minimize the appearance of microorganisms.

One of the distinctive types of metal roofs is that they cool down very quickly after a hot day. Thus, this ability allows you not to transfer unnecessary heat into the house, which can disturb the temperature inside.

When you are installing a metal roof over shingles, this feature may not work. This is because an asphalt roof cools down much more slowly than a metal one. In addition, for it to cool down, the asphalt roof needs air access.

Can you put a metal roof over shingles to avoid overheating the house? Yes, and this can be done in two ways, which we have already described above. You can use a special insulating layer under the metal roof layer. It will hold back heat and prevent the asphalt from heating up.

Likewise, when you install a metal roof on wooden planks, airspace is created that allows both roofs to cool faster. Remember that for the heat transfer to function properly, a good roof installation is required. Monarchy Roofing provides installation metal roofs over shingles in the Toronto area.

Should you Install a Metal Roof over Shingles?

As you may have noticed, the metal roofing over shingles installation has its pros and cons. To decide whether you can put a metal roof over shingles or not, you need to weigh the pros and cons.

It should be understood that no matter how attractive the idea of ​​saving money on installing a new metal roof is, unforeseen problems can arise that will reduce its lifespan. Since the price of a new metal roof is quite high, the professionals at Monarchy Roofing recommend dismantling the old roof before installation.

In this way, you will be completely confident that the deck and plywood are in good condition and you will be able to reap all the benefits of a metal roof over decades. It is also worth understanding that in the case of installing metal roof over shingles warranties the time will be much lower.

However, if you decide to leave the old roof, you need to understand how to install metal roofing over shingles right. Contact the best metal roof contractor in your city for a job evaluation. Each project has its characteristics and this type of metal roof installation will be unacceptable.

If you live in Toronto or neighboring cities, call our number and our professionals will help you choose the type of installation for your new metal roof. We will also show you what type of metal roof would be best suited for your home so that you do not have to worry about its condition for many years.

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