Your home can seem sleek and stylish with metal roofing. It’s also extremely long-lasting, as a metal roof can last more than 45 years on average if it’s well maintained. With these features, installing a metal roof might be a wise investment.

How to install metal roofing over plywood and how long it will last you may wonder. Keep in mind that a metal roof is only as great as the foundation it sits on. If you’re going to put metal roofing over plywood, be sure the wood is in good shape. Furthermore, correct preparation is critical to the effectiveness of your metal roof, such as removing elevated nails and putting waterproof felt.

Metal roofs are available in a broad range of forms, colors, and materials, including aluminum, zinc, and other metals. Regardless of the type of roof you choose to install, knowing the proper procedures is critical.

But you do not need to worry about it. We will guide you through the whole process step by step.

How To Install Metal Roofing Over Plywood?

Installing a metal roof over plywood requires a simple process to go through. But first of all, you have to gather the required tools and materials. 

Required Tools and Materials:

If you want to install a metal roof over plywood by yourself, the first thing you will need to know is the requirements of tools. Not only to install a long-lasting roof but also to ensure your safety, you must have tools with good qualities. 

You can buy materials depending on your budget and the quality of the materials.

Here is a list of tools you will need to install a metal roof over plywood:

1.  Roofer’s felt

2.  Smooth building paper (Or preferably slip sheet)

3.  Utility knife

4.  Hammer

5.  Drill/screw gun

6.  One and a half inches galvanized metal screws

7. Half inches long roofing nails

8.  Metal snips

9. Gutters

10.  Tape measure

11.   Metal flashing

12.   Chalk box and chalk

Prerequisites and Prework:

Before you jump into the section of the installation, you have to do some work to make sure the house is ready for installing a metal roof.

If you are replacing an old roof and placing a new one, you must remove all the old materials. Do not leave a single shingle on the roof.

After you’ve removed the old roofing, the first thing you need to do is search for any damaged plywood sheathing that needs to be replaced. These are huge boards that are affixed to your roof’s rafters and purlins and work as structural support, hurdles between the roof and the lower components of the substructure, and a surface to which you may adhere your underlayment.

It’s also crucial that you choose the appropriate plywood for the project. You should choose the wood that meets the American Plywood Association or Department of Commerce requirements, according to the Metal Construction Association.

An APA stamp will be present on this wood, which will provide the following information:

  • span rating,
  • exposure durability classification,
  • Thickness,
  • veneer grade,
  • panel grade,
  • and mill number.

You should choose plywood that’s at least 15/32 inches thick, and the span rating which you’ll need to ensure matches your other plywood boards. Mainly conducting any replacements or repairs are the most essential figures to take away from this.

Make sure the plywood deck can bear the additional weight of the metal panels. To create a homogeneous deck structure for the metal, the plywood should be clean and devoid of elevated nail heads.

You’ll also need to make sure your plywood is free of dust and debris, as well as any vents, protruding pipes, or other protrusions.

Step by Step Guide to Install Metal Roofing over Plywood:

Now, that you have all the tools and materials at hand, you can start the process of installation. To make the process easier for you, we have broken it down into some steps. Let’s jump into the installation without any delay.

1.  Slip Sheet and Waterproof Felt installation: It’s not a good idea to directly put your roof panels on the plywood. Weather and moisture require a barrier, which is where the underlayment is required.

Lay the roofer’s felt flat on all of your roof’s surfaces, overlapping each and every row by two inches. Cut the felt around any protrusions, such as functioning vents and pipes, with the utility knife. You must ensure that the felt is nice and flat before nailing it down using roofing nails (half inches).

The felt is covered with a slip sheet (you may use building paper instead). It keeps it from ripping and clinging to the roof’s metal panels. You may hold it in place by securing it with some roofing nails.

Choosing not to use underlayment will only save you money in the near run, ranging from a few hundred to a thousand dollars, depending on the size of your home.

You can be able to save thousands of dollars in the future if you follow the steps on how to put metal roofing over plywood.

2.  Flushing and Gutter Installation: Measure the length of the roof’s edge with the tape measure. Using the aviation snips/tin snips, cut and size the flashing material and attach it along the roof’s edge using some half-inch roofing nails.

Some of the valleys may need gutters. In that case, use the snips to trim the gutters. Then use the half-inch roofing nails to fix the gutters at appropriate places.

3.  The First Panel Installation: When you’re ready to begin attaching the panels, you should start at the left and work your way to the right. Begin at the top of the roof and work your way down. Draw a vertical line a quarter inch from the roof’s rake edge using a chalk box. Then square it with the eave.

The section of the roof that lies above the house is known as the rake edge. It allows water to drain off the roof and fall on the ground.

Put the first metal panel on the roof’s left side at the bottom. Working up toward the ridge, overlap the roof’s edge by an inch. Attach the panels to the decking with the half-inch galvanized metal screws. A screw should be placed every 12 to 16 inches.

4.  First Column Installation: After the first metal panel is in place, you may begin installing the remaining panels. You need to finish placing the panels to the roof’s highest point. Then you have to return to the lowest part of the page to begin the next column.

Place the second panel exactly on top of the first, with the edge overhanging by about 12 inches. Install the panel with metal screws in the same manner as the first.

In this process, continue to place the panels all the way up to the top. At the roof’s apex, trim the final panels with metal snips. Always double-check your measurements and cut just once.

5.  Installation of Rest of the Panels: It’s now time to start putting in the next column. Begin at the bottom of the roof and place the panel a bit overriding the installed panel. Now, put the new panel’s initial left-side rib over the final right-side rib of the existing panel.

Do this process repeatedly until the roof is completely covered.

6.  Finishing the Roof: Place the ridged metal along the roof’s peak. Rubber pipe boot kits should be installed around all vent pipes.

If you follow the instructions sequentially and carefully, you should be able to install metal roofing over plywood by now. But there is another question of which type of metal you should select to install? Let’s see

Materials of Metal Roof:

Which type of material you should use is totally up to you. It will depend on how much you are eager to spend. Different metals have different lifetimes. Some of the metals have extra advantages over others. Here is some example:

1.  Zinc and Copper: A copper roof, for example, may survive for more than 60 years, and if properly maintained, it may last up to more than 100. It’s also one of the quietest metal roofs because of its softness. This feature, however, renders it extremely vulnerable to harm from things like hailstorms.

Due to its softness, it might end up dented rather than pierce. Of course, the benefits of long-lasting, ultra-quiet operation come at a high cost. Per square feet, it may cost between $14 to $25, depending on the quality.

Zinc roofs provide many of the same advantages as copper roofs. And they both have almost the same price as well.

2.  Aluminum: Aluminum roofs can resist rust and may endure up to 50 years. But you should know that the sheets might be thin, making them unsuitable for high-wind settings.

You may have to pay between $4.50 and $10 per square foot for an aluminum roof. If you install your roof yourself, the cost will be lower. Hence, if you hire a professional, the cost will be more.

3.  Steel: Steel roofs are available in a variety of styles and are both durable and cheap. A steel roof can endure up to 40 years, depending on upkeep and weather conditions. Steel roofs range in price from $2 to $7 per square foot, depending on the kind.

There are also tin roofs available but not much popular nowadays.


“How to install metal roofing over plywood?” The question has been answered in detail that you need to know. Metal roofing is a smart choice for homeowners since it is energy efficient and comes in a range of colors that add value to your home.

You can choose the metal considering your budget and you can install it yourself which will make it much cheaper.


As a civil engineer and roofer, I love to share the experience that I have gained through the last couple of years. In the roofing industry, practical experience is a very crucial fact that can help you a lot. Hence, I want to help you with my blog.

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