Your home is built, in the most basic sense, by a roof and four walls. Of course, that includes numerous walls, attics, basements, and intricate roofing and flooring patterns. But in the simplest sense, you and your family are protected by your roof and its four walls. The roof, specifically, protects you and your family from storms and other potential dangers. While you may think this protection is just a simple material placed overhead, a roof is actually a complicated feature to the home. When installed incorrectly, a roof may lack the necessary items to fully protect your family.

To ensure that you get the best protection for your family, make sure you understand the main components of a roof. From the structural backbone to the gutters that keep water from leaking into your home, this guide will showcase all that goes into a successful, protective roof. No matter whether you simply want to update the roof you have now or intend to build your home from scratch, you’ll want to understand all the different facets of a roof and what will provide you with the most protection. Learn more about the different components of a roof here!

Roof Structure:

This grouping of components delves strictly into the various aspects that create the roof’s structure. Think of these as the things you can see when a house is just getting built and it’s only the wood or metal framing. You will see four main parts, and we discuss them below.


One big aspect of a roof’s frame is the rafters. Rafters are a series of sloped structural beams that extend from the peak of the roof to the edge of the roof. They provide the main support for the roof load, and if done incorrectly, it can lead to dipped or collapsed roofs.


Another large aspect of a roof comes from purlins—additional support for the roof load. Where rafters are vertical beams, purlins are horizontal beams laid on top of the principal rafters. Not only do they support the roof but they also tie the rafters together, providing even more stabilization and strength for the rigid framing. These are essential to a strong roof, especially in areas prone to strong winds. Steel purlins eliminate the need for plywood decking, and they provide even more support than their wooden counterparts.


You will also notice the roof’s pitch right from the get-go. The pitch is, quite simply, the slope of the roof. It is expressed as the ratio between the rise and horizontal span of the roof or in terms of the angle of inclination. The framing of the roof determines the pitch of the roof—the rafters and purlins play a large role in this.

Roof Covering:

The next section we’ll discuss is the roof’s covering. There are tons of elements to this part of the roofing process, so we’ll delve into the main components. Without these elements, your roof will not be complete and will not protect your home the way you need it to.


Your home has its entire structure and bones laid out. Next, is the roof’s covering, and that begins with the underlayment. This acts as the last barrier for your home and is a water-resistant material installed directly onto your roof. Most roofing professionals will use asphalt-saturated felt as the underlayment, as it serves as a secondary water barrier if water gets beneath the shingles and decking.


On top of the underlayment is the roof’s decking. This can be made from a variety of materials, but it always acts as reinforcement for the roof structure and provides a nailbed for the shingles. The underlayment and the decking also work as a sort of insulation for the home, keeping moisture from leaking into the attic and causing problems.


Shingles can be made from many different materials, but many popular roofing materials such as asphalt shingles are chosen because of their price, not their longevity. When you choose metal roofing materials, you get a brilliant finish and you maintain better energy efficiency, don’t have to worry about re-roofing, and are much safer from any potential damages.

At American Metal Roofs in Michigan, we supply a variety of different types of metal roofing materials to fit your needs. We have aluminum, galvalume steel, galvanized steel, copper, titanium, and many more choices. We also push it further and include various styles for you to choose from so that you can get the best “look” for your roof—shake, shingle, tile, and slate profiles, standing seam, and sheet roofing—and all of these come in a myriad of colors. You have truly endless options with metal roofing!


One of the most vital parts of your entire roofing system is flashing, which is a type of resistant molding that prevents water from infiltrating the roof. Say you have a chimney—chimneys don’t have shingles or underlayment, and they go straight through the entire roof decking into your home. The sides of the chimney would be left bare and would have nothing to stop water from rushing in at the joints where the chimney meets roof—that’s where flashing comes in. It’s installed around any vertical surface that intersects with the plane of the roof, so it is typically installed around vent pipes, chimneys, skylights, valleys, and roof vents.

Roof’s Edge:

Our final section is about the edge of the roof and what it takes to complete and finalize your roof. These aspects are just as important as the others, as it works to keep water and other elements from leaking into your home.

Drip Edge

Simply put, this is a molding that covers the edge of the roof and reduces any risk of water infiltration from any nooks and crannies in the roof. Though not necessarily required by Code, it is highly recommended by roofers and manufacturers. It will attach directly to the decking along the bottom of the roof slope and above the underlayment.


This is a vertical component of the exterior part of the roof where it meets the edge of the home. It is basically a band under a roof’s edge, and it’s the most visible part of the edge to an observer. Gutters are attached to the fascia.

Roof Gutter and Downspout

The last parts of the roof you should know about are the gutters and downspouts. Gutters are the metal troughs that take water away from the roof’s edge, and they connect to downspouts, which bring the water down and away from the roof’s foundation.

Hopefully, this guide to the main components of a roof will help you the next time you update your home. As we stated, metal roofs are better, so turn to American Metal Roofs in Michigan for all of your metal roofing and installation needs. From our top-notch Centurion roofing to our Terracotta metal roofs, we’ll make sure your family is protected!

Components of a Roof