The anatomy of a roof


Let’s take a practical dive into the anatomy of a roof, unraveling the crucial components that work together to protect your home from the elements. By gaining a deeper understanding of these essential parts, you’ll be better equipped to maintain the integrity of your roof and ensure the safety of your dwelling.


The foundation of the roof, the decking provides a solid base for the other components to be installed upon. 

It is typically made of plywood or oriented strand board (OSB) and is attached to the structural framework of the house.

Ridge Board

Located at the roof’s peak, the ridge board is a horizontal timber or steel beam connecting the rafters’ top ends. 

It provides stability and support to the roof’s structure.

Collar Beam

Positioned horizontally and parallel to the ridge board, the collar beam helps prevent the roof from spreading apart. 

It adds strength and structural integrity to the roof system.


These are sloping beams that support the weight of the roof. 

They extend from the ridge board down to the eaves and provide the framework for the roof’s structure.


A valley is formed where two roof planes intersect. 

It is a critical area prone to water penetration, and proper flashing installation is essential to prevent leaks in this vulnerable area.


Flashing refers to metal strips or sheets installed at various joints and intersections on the roof to prevent water from seeping in. 

It is commonly used around chimneys, skylights, vent pipes, and valleys.


Shingles are the outermost layer of the roof and serve as the primary defense against the elements.

They come in various materials, such as asphalt, wood, metal, or slate, and protect from rain, snow, and UV rays.


A chimney protrudes from the roof and allows for the ventilation of smoke and gases from fireplaces or heating systems.

Proper flashing around the chimney is essential to maintain a watertight seal.

Felt Underlayment

Installed beneath the shingles, the felt underlayment acts as an additional layer of protection against moisture. 

It helps to prevent water infiltration and provides added insulation.

Vent Pipe

Vent pipes are used to vent plumbing and other exhaust gases from the house.

Similar to chimneys, proper flashing around vent pipes is crucial to prevent leaks.


A skylight is a window installed on the roof to allow natural light into the interior space. 

Flashing around skylights is vital to ensure they remain watertight.


Gutters are channels installed along the eaves of the roof to collect and divert rainwater away from the house. 

They help prevent water damage to the roof, walls, and foundation.


Sheathing refers to the boards or panels that are nailed to the rafters or trusses to provide a solid base for the roof covering. 

It contributes to the overall strength and stability of the roof structure.


The fascia is a vertical board that runs along the edge of the roof. 

It provides a finished appearance and serves as a point of attachment for the gutters.

By understanding the various components that make up a roof, you can appreciate the solid structure that protects your home. 

Regular maintenance and inspections by professional roofing companies are crucial to ensure the longevity and durability of your roof. Remember, a solid roof means a secure and protected home.


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