A worker using a nail gun to secure shingles to a roof

What Are the Layers of My Roof and What Do they Do?

The Layers of a Roof

There’s a lot that goes into building a roof. This part of our home is unique in that it directly protects us from the elements. While we usually associate roofs with the shingles visible from the outside, many layers go into a roof that allows it to function for its intended purpose.

All of these layers build on one another to create a barrier against rain, wind, snow for those up north, falling debris, and anything else that may come in contact with our homes.

We’re breaking down the layers of a roof and what you need to know about each one.


This is the most basic level of your roof and is crucial for the structural integrity of your home. If we stripped away our home’s siding and windows and sheetrock, we’d see just plain wood planks. The same goes for the roof.

Behind the shingles and other layers lies wood planks outlining the shape of your roof. This is necessary to prevent the roof from collapsing in on your home. The type of planks and how they are laid out depend on the materials used for the rest of the roof.


In between the planks holding up your roof is insulation, which helps keep your home comfortable and prevents sharp changes in temperature. Insulation will usually be exposed in an attic if the attic is unfinished.

Roof Deck

Another significant part of the roof is the deck, which is a layer of plywood that lays out a foundation for the rest of the roof materials. The plywood covers the framing and creates a solid, flat surface across the entire roof.


On top of the deck is the underlayment, usually made of a felt-like material that prevents water from passing through the roof.

Roofs need to be effective at reducing water penetration in order to prevent damage to the roof itself and leaks in your home. The underlayment covers the entire deck and adds to the protective water barrier.

Weatherproofing & Flashing

Two other waterproofing elements of the roof are weatherproofing/water shields and flashing. Unlike the underlayment, these are spot-specific protection devices, rather than covers for the whole roof.

Water shields are another waterproofing device that will help the roof be resistant to water. These are places around eaves and valleys, which are more vulnerable to water and ice buildup.

Flashing is a metal barrier also used to protect against water damage and penetration. Flashing is placed in locations where different sections of the roof meet and therefore is required to cover any cracks or open spaces. It’s often placed along eaves or around chimneys, skylights, and other roof elements.


There are a lot of materials to choose from when it comes to the outer layer of your roof. Shingles are the most common across the United States because of their durability, lifespan, and low cost. Other common options are tile and metal. Shingles also come in many different colors and shapes, which makes it easy to find one that works for you.

Shingles are the first line of defense for your roof, so it’s crucial that any damaged or missing shingles are repaired by a qualified roofing team.

Experience the Difference

For reliable repair on all your roofing elements, go with the Rhyne Restoration Roofing team. Our skilled roofing experts are ready to help make your roof beautiful and functional. Contact us today at (888) 973-0087 to schedule an appointment for a free estimate!