Roof Anatomy Lingo for Your Familiarization
(To simplify the terminology below, please scroll to the bottom of this page for diagrams)
- Rake Edge - Although its name implies that it is a type of tool, when one is referring to the anatomy of a roof, the rake is actually a certain area of the roof. More precisely, it is the perimeter edge that extends between the ridge and the eave. It typically is perpendicular to both of those parts.The eave and rake both play key roles in keeping water from entering a home.
- Gable - A gable is generally the triangular portion of a wall between the lines of a sloping roof. Its shape is dependent on the structural system implemented.
- Hip - A hip roof is a style of roof in which the roof has four sides which all slope towards the eaves. Hipped roofs, as they are also called, are used in architecture all over the world, and there are a number of variations on the basic design. This type of roof can be a bit challenging to construct, but it requires less support and bracing than some other roof designs, and it creates a very even, solid appearance which some people find aesthetically pleasing.
- Roof Jack - A roof jack is a metal bracket. It is used when shingling a roof. You would place a roof jack against a completed section of shingles and nail it in place. Put an opposing jack in line with the original one and nail down. Now you can place a board across the jacks to keep you or tools from slipping. The board is used as a brace.
- Plumbing Vent - Vent pipes are a vital part of a plumbing system. Most importantly it cancels out any siphon or vacuum caused by the moving water. Vent pipes usually come out of most homes by roof departure and keep all the sewer smells circulating out of the your home.
- Plumbing Vent Pipe Flashing - This type of flashing ties the roof off properly to the plumbing vent pipe.
- Low Profile Attic Vent - This type of vent sits fairly flush to the roof, letting the attic breathe and keeps heat out in the summer and condensation out during the winter.
- Turbines - This type of vent is wind driven, and stands taller than a low profile attic vents. It is usually a larger hole dimension in the attic, still letting the attic breathe, keeping heat out in the summer and condensation out during the winter.
- Gable End Vent - Gable vents go on the ends of the house where the peak is and let the attic breathe. At the top point of the triangle.
- Shingle Covered Ridge Vent - This is where a slot is cut in the top of the ridge of the sheeting along the peaks of your roof. Most vent ridge systems will have an elevated breathable mesh that strips the ridge over the slots. The new ridge cap is installed over the vent ridge mesh. (There are many variations of vent ridge types.) Ridge vents allow a home to properly vent, while disallowing rain or other forms of precipitation to leak into the attic or crawlspace underneath the roof. Equal amounts of cool air and warm air flowing through the vents is paramount for proper heat exchange.
- Gable Roof - A gable roof has two upward sloping sides that meet in middle at the ridge. To be a true gable, both sides must slope at the same angle. Viewed from the end, the shape of a gable roof appears as a symmetrical triangle. Gable roofs are the most common style of roof in the United States. They are popular in areas that receive substantial snowfall.
- Deck - Roof decking is the solid sheeting which shingles are secured to.
- Felt Undrelayment - Felt paper, more commonly known as tar paper, is the underlayment placed on a roof before shingles are nailed on. This covering essentially seals the roof and acts as a moisture barrier, and is just as essential as putting on shingles. Virtually every roof that is shingled will have a layer of felt applied, and as long as it stays covered, will last as long as the shingles themselves.
- Ridge- The roof ridge runs horizontally along the highest point of the roof, and it’s the simplest of all roof components to replace. Roof ridge shingles fold over the ridge, overlapping the uppermost shingles on the sides.
- Roof Vent - A properly vented roof is vital to the performance of the insulation and the roofing system itself. An improperly or inadequately vented roof can lead to condensation on the underside of the roof. This condensation can cause the roof structure to rot and can drip into the insulation, ruining it and causing mold.
- Valley - A valley is defined as the trough formed where two adjacent slopes of a roof meet. Every pitched roof has one or more peaks, and some pitched roofs have one or more valleys. Valleys can be difficult areas in which to properly install composition shingles. Use any of three shingle installation methods devised to provide a watertight covering for valleys.
- Flashing - Roof flashing is considered the last line of your roof's defense against water damage. It's essentially a thin strip of aluminum, galvanized metal, copper, or lead bent in a sharp 90-degree angle to make an "L" shape. These strips sit, pressed up against the base of roof penetrations such as chimneys, vents, skylights, etc. on the roof. They overhang the sides on the perimeter of the roof and cover all the joints of the roof's planes, such as the line along the roof peak and where two roof planes meet. They cover any joint where it would be possible for water to leak in.
- Chimney Flashing - A chimney is an area of the roof particularly vulnerable to water damage. Chimney flashing creates a water-resistant shell around the chimney, but flashing can be damaged, resulting in leaks. Repairing chimney flashing is dicey. Once the system of overlapping metal plates is compromised, sealing provides only a temporary fix. The best tactic for repairing damaged chimney flashing is to remove the old material and replace it. This will cost a little more and take some time, but in the long run, your house will be better protected from severe damage caused by leaky flashing.
- Chimney Saddles / Crickets - The chimney cricket is placed on the high side of a brick chimney on a peaked roof. The actual cricket is a V-shaped, peaked piece of metal set into the small valley that invariably occurs above a square chimney. The cricket is designed to shed water to both sides, so moisture doesn't collect behind the chimney. The function Also called a saddle, a cricket can be used in other roofing situations, besides a chimney. However, the purpose is always the same. It's used to divert roof runoff areas where water can collect. A cricket might also be placed where two sections of roof meet and form a valley. Not all chimneys have a sadlle, or cricket as usually this are used for a wider chimnney.
- Soffitt - A soffit is the horizontal strip of timber that sits on the underside of the eave, the overhanging portion of a roof. Soffits are prone to rotting and water damage because of their location. Often, inadequate gutters or badly designed waterproofing methods are to blame for soggy, crumbling soffits.
- Soffitt Vents - Soffit vents help contribute to the overall ventilation of an attic. Coupled with ridge vents, they allow for a continuous flow of air through the attic. This airflow reduces condensation, which extends the life of the roof and prevents mold. It also helps lower the cost of air conditioning because it prevents heat from building up in the attic in the summer. To ensure proper ventilation, calculate the correct number of soffit vents for your home.
- Rafter - Roof rafters are one of the most important parts of any type of roof. They are generally made of two-by-four lumber and are used to form the pitch of a roof. They come from each side of the roof and meet in the middle to form what looks like a V.
- Plywood Sheeting - Roof sheeting is the wood deck of which shingles are fastened to after felt paper is installed. It is used to protect the roofs of houses, sheds, or garages from the elements. It is a very important part of all aspects of construction. Many different types of roof sheeting are available to choose from and each type has its strengths and weaknesses.
- Eave - The eave is the horizontal edge that sticks out past the exterior wall. Because the rake and eave are vulnerable areas, they need reinforcements to help keep a structure from sustaining water damage.
- Eave, Ice, and Snow Guard - Snow guards are small brackets that home and business owners mount to their sloping roofs to prevent snow or ice from falling to the ground. These guards hold the snow in place until temperatures rise above freezing and can melt away the snow. Without these guards, accumulated snow can pose a threat to bystanders below and cause damage to gutters, shingles, tree branches and vehicles.
- Fascia - The final additions to the trim and roof are the installation of fascia and soffit. The fascia may be made of vinyl or wood. Using wood is a bit more challenging and is also a bit more prone to rot if moisture gets behind it and attacks the rafter ends. Installation requires a period of dry hot days to dry the wood before placement. Your gutter sytem fastens to the fascia.
- Space Inside / Field of Roof - The field is the larger ares of the roof which are most out in the open and generally have no rooof penetrations.
- Skylight - Skylights, weather domes or flat syle, are usually found on houses. Skylights with domes add natural sunlight to a room and can brighten up a room that does not normally get much sun. Rain and hail damage can cause the plastic domes on skylights to crack and need to be repaired. Replacing the entire skylight, even where one is already installed, can be a difficult and costly job.
- Skylight Flashing - Skylights have become an almost standard feature in the modern home to bring in additional natural light or enhance a room's ventilation. Available in a variety of shapes and sizes -- domed or flat, fixed or operable -- with clear or opaque acrylic panels, there is a skylight design for almost any application or need. Whether adding a new skylight unit or replacing the roofing around an existing unit, the proper installation of the flashing is essential to insuring a watertight seal and years of maintenance-free functionality.
- Skylight / Curb and Frame in Place - The two most common types of skylights installed today are curbed-mounted skylight and the frame-in-place skylight. Curb-mounted skylights sit inside a wooden frame built especially for the skylight opening. This curb has special flashing on it to make the skylight's opening resistant to water leaks. The curb sits on top of the roof line, but the flashing does integrate with the shingles on the roof. A frame-in-place skylight has an opening built flush with the roof line. The skylight sits inside the frame. Flashing is also in place with this skylight installation, and the framing materials integrate with the shingles to prevent water from entering the building.
- Dormer - A dormer is an extension off a roof to provide more space or more light in an area. A roof may have one dormer or several, small dormers with single windows or wide ones with several openings. Some dormers have simple shed roofs with a single slope, while others have gable or hip roofs to match the roof of the house.
- Drip Edge - To help guide rainwater or melted snow into the gutters, a drip edge is often necessary. When a drip edge is not present, stray drops of water can cling to the roof and result in deterioration of the materials. However, with a drip edge in place around the rake and eaves, runoff from the roof drains into the gutter properly.
- Gutter - The gutters collect water and carry it away from the foundation of the building, instead draining it out a safe distance away on the ground. If no gutters are installed, water often pools around a building's foundation and causes leaks.
- Header Wall Flashing - A header is at the base of a dormer along a straight wall that ties into the roof. Flashing is needed for the areas where your home meets up with an addition.
- Step Flashed Wall - Every roof junction needs to be sealed against rain, snow or other moisture. That's every place two roof lines connect or a roof intersects with a vertical element, like a wall or a chimney. Every type of roofing material needs this flashing, whether it's traditional asphalt shingles or wood cedar shakes. The best way to apply this with shingles is step flashing, so called because it steps up and around the seam. It needs to be installed at the same time as shingles so that sections of flashing and shingles can be overlapped.
- Cupola - Cupolas are a popular way to add character to roof tops. They have a long history and have been integrated into modern architecture as a way to bring light and air into a home or business.