How to Install Metal Roofing Over Shingles?


As our community is rapidly doubling, the construction business and industry have also evolved, accommodating millions of residents. Erecting a building can be exciting and overwhelming at the same time. The owners need to be present in all the stages to meticulously correct and spot the flaws that can be modified instantly. It can be time-consuming as construction involves being well prepared to plan the budget and then deciding what finish to use. It is essential to ensure what material, quality, and kinds of concrete or cement would be utilized, what category of electrical or heating will be introduced in the house, the roof types needed to be placed over the top, and its quality. Additionally, the material involved should be available in exact measurements and fall under the budget. Moreover, it is a task of an entire community of architects, laborers, vendors, and contractors who combine their understandings and knowledge to create a beautiful structure at the end. One needs to be mindful of the design, construction, and groundwork needed for to roof. Different roof materials and quality work is available but chosen by the homeowners depending on their style, preference, budget, and weather.

Roof shingles are defined as roof covering in which the elements are individually overlapped. They are available in flat and rectangular shapes laid in uniformity, starting from the bottom edge to the upper portion, which overlay each other. Shingles are manufactured from wood, slate, plastic, and metal. These discrete elements are thin but shaped pieces of wood used as a wall of roof covering. They are available in a variety of colors and act as a defensive fence. They are considered the most straightforward roofing material installed as they are easy to divide, fasten, and grip. However, it is not ideal for placing shingles on metal roofs and is considered a safety hazard. Although installing grooved metal roofing over asphalt shingles seems appropriate, installing shingles over a corrugated metal roof would not be sensible and practical. Getting a completely new roof is unavoidable in some circumstances, especially for homeowners, investors, and realtors. Unless the owners buy a new property, replacing the roof will render major maintenance expenditures, which is why shingles remain the top priority of many people. They are extremely affordable, and most people use asphalt or fiberglass shingles.

If you already have a shingle roof and desire to replace it with a metal roof, you need to take off the previous shingle roof, as argued by most experts. A metal roof cannot be easily fit over the shingles because of the total weight. This characteristic makes it harder to be installed over shingles, and there are specific considerations to be addressed. Check with the local building department to see if it is one of their checked installation methods. The shingles also need to be super flat; otherwise, it is not practical to directly install the metal roof over existing shingles. Finally, if shingles are not balanced, the supporting structure would not tolerate the total weight of shingles and the metal.

How to install metal roofing over shingles?

To install metal roofing over shingles, you need to do the following steps:

  • Begin by placing a large waste bin alongside to remove the scraping of shingles. Sometimes a single typical layer of shingles can weigh around 225 pounds (lb) per 100 square feet. Therefore, it is better to throw the singles directly into the bin from the roof; otherwise, it can get messy.
  • Protection. Hide the shrubs (safety) under the roof space with the help of plastic layers while removing shingles. Reduce the mess, protect the plants.
  •  Use a crowbar to loosen your chimneys around roof features.
  • Place the front edge (carefully) of the shingle excavator (slowly ) under the lower corner of the front row of shingles.
  •  Begin with the top row of roof shingles and loosen them in a structure. After completing the first row, go to the second and repeat, taking out the nails row by row. Continue this excavation until you reach the last row.
  •  After pulling out the shingles, scrape off the remaining nails that might be embedded in the roof skin with the help of a crowbar or a hammer claw.
  • A spatula can be used to remove the roof tiles. In that case, you will protect ventilation airways.
  •  Lastly, use a broom and sweep across the house floor to gather all the nails that might have fallen during the scraping process.


However, despite discussing the installation of metal roofs and shingles, specific platforms support the setting up of metal roofs on shingles. Metal roofs are known for their durability and versatility, which is why they can be a better option than a shingle roof. There is, however, one drawback, which is the high cost of metal, due to which many people skip investing in a metal roof. After all, scraping off old shingles sheets can double the price and complicate the existing work. Due to which many people look for the possibility of installing a metal roof over shingles. There are countless benefits of installing a metal roof on top of shingles, and there is no need to remove the old roof. One of the prominent advantages is that it is lightweight, making it ideal for installing an existing roof.

Good quality of shingles

If you decide to put a metal roof on top of the shingles, you need to consider the roof quality before the commencement process. Almost every building department will stress the significance of safety as the shingles need to be in good shape and condition to install a metal roof on top of it. The safety experts will ensure that the shingle roof’s plywood is in excellent shape and does not contain any holes or soft spots. A metal roof will be installed correctly and drilled with the help of screws, so it is imperative to check the fundamental layer on which it will be inserted. Soft or damaged plywood may reduce the chances of durable and sturdy metal fitting and can pose a safety threat during extreme weather conditions.

Consider the building standard codes.

Various locations have different municipal codes of conduct for building construction. For example, you cannot have more than two roofing layers on a single residential house in Florida. The reason is that these houses were only designed to bear a small amount of weight. If multiple layers are applied on the rooftop, then there is a high chance of strings disintegrating. As a result, some countries encourage homeowners to take off shingle roofs before installing a new one to avoid damage. Even if you intend to keep a single layer of the top, whether metal or shingle, you can only opt for one because of safety issues.

There are two defined methods of applying metal roof layering over shingles. The basic process is implementing a new underlayment over an existing shingle roof; this way, the new layer will cover the old shingles. This new layer will act as a defense when water enters the top. It also acts as a buffer between the two layers as the coating tends to protect the shingles granules if they start wearing off. The second method inculcates installing metal roofs with purlins or battens. The purlins are drilled down to the roof deck depending on the construction of metal roofing. The metal is then placed on the purlins and gives a flat surface to implement the metal roof panels without the grooves and flaws in a shingle roof.

If you decide to install a metal roof over the existing single roof, it would cost you under the budget and offer many benefits. It is long-lasting and durable as a properly drilled metal roof with screws will last more than 40 or 50 years before replacement. It is naturally water-resistant, bearing extreme weather conditions such as intense winds and tingling summer heat. Metal roofs are mostly low maintenance and do not require regular inspections or repair jobs because of their strength and quality. Many people also prefer metal roofs because of the lowered cooling bills. The unique metal coating reflects and absorbs heat rather than absorbs it, giving a cooler summer temperature.

Mark Brown

Mark Brown

Mark Brown is a construction engineer from California who has been working as an independent contractor and writer for the past 15 years. From 2022 onwards, Mark has also been contributing author of home repair articles at nimblefreelancer.com. Read more on Mark Brown's biography page. Contact Mark: mark@nimblefreelancer.com

Inflation Is Eating IRA/401(k) Savings! How to Protect Your IRA/401(k) in Bad Times?

VISIT GOLD IRA

Recent Posts