How to Cut Tin Metal Roofing and Roof Panels

Metal roofing close up

If you’re looking to replace the roofing on the storage shed or are building a small garage or treehouse, you might consider cutting your own metal roofing instead of hiring someone to do it for you. Learning how to cut metal roofing isn’t as tricky as you might think. Although it does require the use of a power tool, even novice craftsmen can make good metal roofs with a minimum of effort and practice.

Simple Metal and Tin Roofing Overview

We’ll go through a step-by-step process that takes you all the way through picking out the materials for your metal roofing and show you how to use those materials with the right tools to get the job done. While the exact material you use may vary, the general guidelines below will work for all metal roofing projects.

Why Cut Your Own Roofing

While it’s true that you could hire someone to cut your metal roofing, there are a number of benefits to doing the task yourself. These major benefits are:

  • ​being able to cut the metal roofing to your exact specifications
  • ​being able to choose the type of metal roofing
  • ​being able to make modifications or adjustments on the fly without it costing extra

All of these are aspects that would be harder to execute on if you hired someone to do the job for you. The truth is that cutting metal roofing is quite easy (​it's ​as simple as cutting galvanized pipe) and it doesn’t take much advanced experience or effort. 

Even beginners can effectively cut their own metal roofing and add a personal touch to their home improvement or construction project.

Metal roofing close up

Knowing how to cut your own metal roofing will also allow you to make repairs for much cheaper in the future. For instance, if your storage or toolshed's roof trusses ends up needing a ​repair, you can do it yourself for much less money than if you hired someone to come out and do it for you.

You can also use the skills learned here to create metal roofing for dog houses, treehouses, or sheds. The practical applications of what you’re about to learn are limitless.

Materials Needed

To cut metal roofing safely and effectively, you’ll need a certain set of materials on hand to complete all the processes. In particular, you’ll need:

Getting your hands on all of these materials should be fairly easy, especially if you’ve already done some construction work in the past. 

Markers

Markers can be found in any standard hardware store or even general stores like Target.

Corrugated Metal Panels

Corrugated metal panels can be purchased at hardware stores as well. When buying, it’s a good idea to purchase a little more roofing than you think you might need. 

Even experienced craftsmen can make small mistakes and you need to have some extra roofing on hand so you can complete your project without having to scrap everything else.

To do this, purchase about ten percent more roofing than your measurements predict. This is enough extra roofing to afford you some wiggle room in the event of a mistake but it’s not so much extra roofing that you should have trouble storing it after you’re all finished.

Work Surface

For the a work surface, there are several different ways to approach it. 

On the simple side, any solid craftsman table will do. You can also use a bench, but the key part is to find a surface that isn't likely to move in the middle of shearing. You can mess up your cut or cause injury to yourself if you're cutting service isn't stable for the duration of your efforts.

You can use weights or blocks of some kind to ensure that your cutting surface remains stable during shearing if necessary. 

By far, the best cutting surface is a workbench. Not only is it already meant to be stable and perfect for use with power tools, but it goes perfectly with a cutting circular saw if you prefer to use that kind of tool over power shears.

Workbenches are great for cutting your corrugated metal sheets. If you have one, we highly recommend you use it over any other service. If you don’t, you can usually find workbenches online or in hardware stores. You can also build your own in the backyard if you have woodworking experience!

​If you prefer hitting two brids with one stone, then looking into an affordable table saw on the market might be a good idea too.

Tools Needed

You’ll also need an assortment of tools to cut your metal roofing effectively. The primary factor to consider is what tool you’ll be using for cutting the metal.

At its most basic element, you can cut the tin roofing with power shears. However, you can also use a variety of other saws to make the cuts.

Simple DIY Metal Cutting

If you’re going simple, here is a base set of tools you’ll need:

​Measuring tape and a combination square both purchased at a standard hardware store. Power shears can be as well, though you may wish to get something that’s strong enough to cut through the kind of metal you’ll be using for your roofing.

Power shears are handheld power tools that look somewhat like drills. They make cutting through metal extremely easy and don't require too much power tool experience to use. We'd recommend using power shears over the other options since they strike a balance between speed and efficiency and opportunity for accuracy. 

A view of an old metal roof

Most metal roofing projects use tin or metal of similar thickness, and power shears shouldn’t have any trouble cutting through this.

Alternative Tools to Cut Metal

If you’d rather use something other than power shears, there are a few choices available to you.

Cutting Saw

These circular saws are great for cutting through tin or other thin metal roofing materials. However, you need to have plenty of experience with a circular cutting saw before you use it for a project like this. 

In addition, cutting saws require that you use specialty blades that are designed for cutting metal, even tin. This requires you to purchase some extra supplies ahead of time.

Cutting saws have an advantage since they’re extremely stable and aren’t likely to lead to accuracy mistakes. They are best used with a workbench where they can be mounted safely.

Tin Snips

These are hand tools that don’t require power to use. Instead, they’re essentially scissors for tin. You should only use tin snips for this kind of metal roofing.

This tool is extraordinarily cheap and easy to use and they ​it forces you to go slowly which may improve your accuracy. You should only consider using tin snips if you’re going to take your time and have the hand endurance to maintain steadiness throughout the effort.

One final thing to note is that there are right-handed and left-handed tin snips available for purchase from hardware stores depending on your orientation. Make sure you get the right kind of snips for your hand!

Nibblers

Nibblers are small attachments that you place on your electrical drill, so they require you to have an electrical drill beforehand. They cut out small bits of metal one at a time and are ideal for cutting curves as well as straight lines. This attachment is a little more advanced than the other tool types, so only craftsman with steady hands should consider using these.

They are ideal for cutting around pipes and other curved roadblocks that might interrupt your roofing layout.

How to Cut Metal Roofing

Now let’s get into the details. Here is the step-by-step process for cutting tin and corrugated metal roofing:

Plan and Mark Your Cuts

First off, you need to plan your cuts before you do anything else. Planning is integral to every construction project and it’s no different when cutting metal roofing. 

Planning out your cuts will save you time and energy and prevent you from accidentally cutting too small a piece out of the roofing material you purchased.

It’s important to take your time during this part of the process. Most major mistakes occur during the planning aspect of cutting metal roofing. 

  1. 1
    ​Use a tape measure and a permanent marker or another marking tool to figure out where you’ll be cutting.
  2. 2
    ​You can use a carpenter square or a standard 2 x 4 board to keep your lines straight and your markings precise.
  3. 3
    ​One other thing to keep in mind is that you need to mark on both sides of the metal. This will help you make your cuts cleanly and accurately, no matter which side of the metal piece you’re looking at.
  4. 4
    When measuring, make sure that you start square. To do this, make every vertical line that you measure run square according to your eave. This helps account for the tilt inherent in roofing materials and won’t compromise your sizing as a result.
  5. 5
    Use the tape measure and a marker to make your initial measurements, then use the combination square and drag it across the cut line.
  6. 6
    Repeat this until you have all of the metal roofing pieces you need for your project.

Start Your Cuts

​Just like with measuring, the key to this step is going slowly and taking your time. There’s no rush to get this project finished except your own schedule.

It’s far better to take a little longer to complete your roofing project accurately than it is to make a bunch of mistakes which can cost you even more time and money. It's truly as simple as cutting vinyl siding for your home.

  1. 1
    ​Place your metal sheets on your chosen cutting surface.
  2. 2
    ​Use your power shears or alternate tool to carefully cut along the corrugated metal markings.
  3. 3
    ​You should go slowly during this part of the process to avoid blemishing the metal or making any mistakes.
  4. 4
    Push your shears gradually along your corrugated panels until all your cuts are complete.

​Push Through Tough Patches

You may discover that your power shears run into a dead end or some kind of resistance in the corrugated metal sheet. This isn’t necessarily a problem that your shears can’t handle.

Sometimes the corrugated metal has an impurity or has crumpled up minutely right at the edge of your shear blade. 

If this happens, the best way to tackle the problem is to move the power shear slightly up so that the blade is resting on a downward angle.

Then, carefully cut through the section with gravity assisting you. This new angle should allow the shears to cut through the roadblock without much issue. Go extra slowly if this happens to avoid making a jagged line.

Top view of metal roofing

Bonus: Install Your Roofing

Once your roofing has been cut, you can now move on to the installation step. This usually involves making sure that you cut them properly and they light up together at square angles.

Installation relies on using fastening strips and screws. Once again, go slowly and carefully during this step in case one of your corrugated metal panels was cut slightly off and needs to be replaced.

If this is the case, the extra corrugated metal you purchase will come into play. You can make a replacement panel without having to go back to the store following the same steps above. 

Conclusion

As you can see, cutting metal roofing is doable even if you aren’t the most experienced handyman. But doing it yourself can save you a lot of money and you can take pride in your personal touch when the project is complete. Thanks for reading!