A Guide to Roofing Terminology

If you’re a homeowner, it’s likely that you will come across some unfamiliar roofing terms. Knowing the meaning of these terms can help you better understand your roof and any potential repairs or maintenance it may require. To give you a better understanding of roofing terminology, let’s explore some common words and phrases associated with roofs and roofing systems.  

Pitch / Slope  

The pitch of a roof is a measure of its steepness. It is usually expressed as the ratio between the rise — the vertical distance between two points on the same horizontal plane — and the run — the horizontal distance between those two points. Generally speaking, flat or low-slope roofs have a pitch below 3-in-12 (meaning they rise 3 inches per foot horizontally) while steep-slope roofs have pitches above 4-in-12 (meaning they rise 4 inches per foot horizontally).  

Decking / Sheathing  

Decking, also known as sheathing, refers to the structural layer that supports your roofing materials. This layer can be made from plywood or other materials such as particle board or cement board. The decking provides structural stability for your roof and serves as an attachment point for shingles and other components. Decking must be properly spaced in order to provide adequate support for your roof system.   

Flashing  

Flashing describes thin metal sheets used to cover joints in roofs and walls where water could otherwise enter through cracks or crevices. Flashing prevents water damage by providing an additional barrier against moisture intrusion at vulnerable areas around vents, skylights, chimneys, or valleys in your roofline. It also helps direct rainwater away from these vulnerable locations so that it doesn’t seep into your home’s structure.   

Roofs are complex structures made up of many different components that work together to protect you from the elements while providing an attractive exterior appearance for your home. Understanding basic terms related to roofs can help you become more informed about maintenance needs or any repair issues that may arise down the road. We hope this glossary has provided some clarity about common words used by professionals when discussing roofs and their various components. With this knowledge under your belt, you now have a better understanding of how all parts work together to form a complete system!