Learn Roofs Inside Out from this Comprehensive Guide
We all need a roof over our heads, but what are the parts of a roof called? Knowing your roof component parts is a good way for every homeowner to keep up with your contractors, showing that you understand the field terms so your builder doesn't attempt to take advantage of you. Understanding the different parts of a roof also gives you an advantage when seeking repairs or replacements from a roofer, as you can ask for exactly what you need with more confidence, leaving less up to guesswork.
We’ve put together this guide on the different roof parts’ names, in addition to what the function of each part is, so you can feel more natural talking to roofers and repairmen from now on.
Note: This list is mostly applicable to sloped or pitched roofs, with flat-roofed homes having far fewer features.
1. Asphalt Shingle
These are the roof components that you’re likely to be most familiar with, being the parts of the roof that most commonly need a roofer to replace or repair for better waterproofing. Most shingles are essentially asphalt material and fiberglass tiles, which can come in either the 3-tab or architectural types, providing your roof with protection against rain, wind, and the elements in general. Shingles can also take the form of other types of materials, with some homes featuring traditional tiles, wooden, or metal shingles, among other shingle for aesthetic reasons. Be sure your roofer follows the manufacturers installation instructions when installing your chosen shingle.
2. Felt Underlay Membrane
Underneath the shingles, you’ll find the felt underlay membrane. This is essentially the final layer that keeps your decking protected from the elements (more on that next), It also keeps the shingles protected from the resin that the decking might release. The underlay will generally be made of some sort of synthetic or composite felt and should be excellent at waterproofing to some degree for maximum efficacy. The whole roof deck sheathing surface should be covered by a roof worker during installation `to keep the whole surface from leaking.
3. Roof Decking / Battens
One of the most important structural parts of a house roof is that it gives the structure some real body. The decking is essentially a fairly thin plywood board that’s laid and nailed over the frame of all the roof areas, so the rest of the elements can be installed. Think of it sort of like the floor of the roof.
Alternatively, this part of the roof can be set up with battens on top of the decking. Battens are essentially extra planks placed on top of the decking for your shingle to be installed onto directly.
4. The Eaves
Eave is the name given to the edge of the roof that sticks out, overhanging vertical walls to prevent them from coming into contact with too much rainwater. The dangers of water damage are well recorded, which makes it clear why a good eave is so important to a well protected roof and home.
5. The Gutter
The gutter piece sits beneath the eaves, collecting all the rainwater runoff from the roof and funneling it through the downpipe. It’s important to keep an eye on and regularly clean your gutters, because if they become blocked with leaf matter or debris it could cause leaks, drippage, and splashing that could end up damaging the external walls of your home. Gutters come in all different types and styles
With every gutter, there must be a downpipe. The downspouts on a gutters system is essentially a closed gutter that runs down the side of the house, leading down to a drain, ensuring that water doesn’t just pool up near the house.
7. The Ridge
This is the name given to the top of a house roof, where the two diagonal parts of the structure meet. The ridge of the roof has to be lined with its own layer of shingles to ensure that it doesn’t become compromised by winds or water damage. Under these shingles is a ridge board, made from wood or metal, which is where the rafters/trusses meet under the decking.
The rafters or trusses are essentially the boards that give the roof its foundation. They run from the main structure of the house pitched at an angle, meeting at the apex of the roof, giving roofs their typical triangular shape. All roofs are supported by rafters.
Joists run horizontally across the width of the roof, meeting the bottom ends of the rafters in the structure. The joists are essentially the basis of the structure of the indoor ceiling. Joists are also the structural component that holds up dormer windows.
10. Purlins / Collar Beams
Purlins run perpendicular to joists, positioned slightly higher up, and connected to the bottom of the rafters/trusses. They provide further support, keeping things steadier than the rafters and joists alone. Purlins are also known as collar beams.
Flashing is a protective material that can be found in every part of a roof where you might find joints. It’s generally a type of metal sheeting made from galvanized steel or aluminum, or sometimes plastic, that’s used by your roofer to keep moisture from penetrating the roof through openings. You’ll find flashing in the valleys of the roof, along with the bases of chimneys, roof vents, plumbing vents, and walls.
The chimney is a vertical column that comes out the top of the roof, providing a place for smoke and combustion gas to leave the house. Chimneys generally lead up from fireplaces, boilers, and indoor stoves, designed for ventilation so homes aren’t filled with smoke or dangerous gases.
13. Plumbing Vents
The plumbing vent of the roof is a pipe that comes out the top of the house, designed to allow airflow into the plumbing system. Plumbing requires air to operate properly, as it allows wastewater to flow into the sewage or septic-system leaching field.
14. Roof Vents
Along with the chimney and plumbing vents that release gases and ventilate in air for the sake of functional operations within the home, There are also roof vents designed for the simple ventilation of the attic space. The best roof vents are constructed to stand above the highest point of the roof, with four open vented sides for directing airflow in from every direction. Made from perforated aluminum, they lead to air inlets at the edge of the roof, bringing air into the attic to ensure that it’s well ventilated.
The valleys are the points on roofs where two opposing slopes meet, such as the joint between the primary roof and a dormer. Valleys require their own designated underlayment and flashing to stay safe and secure from leaking.
16. Dormer Window
A dormer is a window that sticks out vertically from the side of the primary roof, with its own walls and roofing set up. It’s built from lookout boards and its own smaller rafters/trusses. The rafters of a dormer are formally known as rakes. Quite often they are installed for aesthetic reasons.
17. Gable Window
As an alternative to the dormer window, a gable window is installed directly into the walls of the house, rather than into a separate vertical structure. A gable window can offer a view of the outside world from an attic or upstairs space in the home.
18. The Attic
The attic is the space underneath the main decking of the roof. Even if you can’t use it, every home has an attic, while some are bigger than others and have a more helpful purpose. Some people use their attic to set up a new bedroom or for storage, while other attics may simply exist as a space under the roofing parts. Make sure you insulate your attic to keep the
heat out and the cool in.
19. A skylight is a type of window installed directly into the roof, facing upwards rather than outwards like a gable or dormer windows. Skylights can be very handy for getting some light into attic bedrooms, or in the upstairs rooms of converted bungalows, while they’re also often used as stylistic choices in more open spaces in homes with higher ceilings. Make sure your roofer uses window tape during installation.
There are so many elements of roofing material that we couldn’t fit all of them into this article, but based off the value and expertise we've offered you here, you should feel far more confident when entering discussions with contractors, & roofers to service or have your roof repaired. It’s also worth remembering that not every home is the same, so while many of these elements will undoubtedly feature on your roof, there will be others that don’t.
With all of this information, you can debate and negotiate easier than ever, but remember it’s not your responsibility to be an expert on roofing, and a good roofer should guide you through the process with empathy and leave the choice up to you. Be sure to have your roof inspected yearly for proper maintenance.
If you need a trustworthy, reliable roofer, Get in Touch With Us, we’ll make the process as smooth and easy as we can.