Understanding the Terms for Roofing
05 March 2018
It’s good to know some of the terms for roofing, as you’ll be able to make the right decisions when it comes to choosing the types of materials for your roof which can create a good match to the existing style of your home and your place of residence. Additionally, you’ll get to figure out the terms used in the roofing contract and get to update yourself on the progress of your project.
Common terminologies used in roofing are such as:
1. Asphalt. This is a substance, waterproof in nature and fastened to the materials of the roof during the process of manufacturing.
2. Asphalt plastic roofing cement. This is a type of sealant made of asphalt and its function is to attach roofing substances together. Other names for it are flashing cement, roof tar, bull and mastic.
3. Back surfacing. This is a type of granule placed on the back part of a shingle to prevent it from sticking with one another during the process of storage and delivery.
4. Base flashing. This is a kind of flashing fastened to the deck or just resting on it. The purpose is to channel the movement of water at the rooftop.
5. Built-up roof. This is a term used to describe different layers of asphalt when they are bundled together. The same term is used to describe layers of ply sheets.
6. Butt edge. The term describes the end part of a single tab.
7. Caulk. This is an act of filling an intersection to avoid leakage.
8. Closed valley. This occurs when a shingle covers a valley flashing.
9. Coating. This is the application of one layer of asphalt to the external surface of the roof and the purpose is to provide protection to the roofing membranes.
10. Collar. This is a flange in a preformed condition whereby it is installed above a vent pipe for the purpose of sealing the roof area surrounding the opening of the vent pipe. Another term for it is ‘vent sleeve’.
11. Concealed nail technique. This is the process of applying the roll roofing whereby every nail is concealed via cement, creating an overlapping course.
12. Counter flashing. The flashing’s counterpart fastened to a surface with vertical position located over the roof’s plane. The purpose is to block movement of water from shifting toward the area behind the base flashing.
13. Course. This is to describe shingles in a row and the row can be arranged in a horizontal, diagonal or vertical manner.
14. Cricket. This is a water diverter placed at the chimney’s backside and the purpose is to stop snow and ice dams from accumulating and to promote water deflection.
15. Deck. This is the upper part of a roof surface in a position where the roof is already installed. Deck is also used to describe the installation of a surface in order to support framing members.
16. Double coverage. This is to describe an asphalt roofing system whereby the overlapping area is at a minimum of 2” wider than the area which is exposed. Double coverage produces 2 layers of roofing substances on top of a deck.
17. Downspout. This is a type of pipe used to drain out rainwater from gutters. Another similar term for downspout is ‘leader’.
18. Drip edge. This is a flashing that comes in the shape of ‘L’. It is utilized together with the eaves and rakes. The purpose is to promote free flow of water toward the gutters. It is also used to stop any drippings caused by improper construction.
19. Eaves. These are parts of the roof and they overhang or extend in an outward manner. They are not positioned exactly above the external part of the walls or the internal part of the building.
20. Exposed nail method. This is to describe a roll roofing system during the application to the roof. The nails are inserted right into the intersecting course but the nails are not covered.
21. Fascia. This is a board consisted of a wood trim and its purpose is to hide the edge of the rafters and sheathings.
22. Felt. This is a fiber-based substance serving the purpose of an underlayment or sheathings. It is also used to describe the substances of roll roofing.
23. Flashing. A flashing is comprised of metal pieces or rolled roofs and its purpose is to seal water surrounding the vent pipe, chimney, intersecting wall, dormer and valley.
24. Gable. This is the edge of the external part of a wall where it forms a triangle shape at a sloping roof’s ridge.
25. Granules. These are small, bead-like pebbles created from heated and crushed rocks. Granules are coated with ceramic and are used in the form of protective coating or surface of asphalt shingles.
26. This is a type of narrow but open container which directs water originating from the eaves and moving toward the downspout. In normal circumstances a gutter is fastened to a fascia.
27. Head lap. This is to describe shingles when they are overlapped. The same term is also used to describe the top end of roofing felts.
28. Hip. This is when a couple of sloping roof planes are intersecting with one another, forming a vertical ridge or a fold.
29. Ice dam. This is the formation of ice due to the accumulation of trapped water on the eaves and the frequent shifts of freezing and thawing of snow on the overhangs. Ice dams can also channel full forces of water beneath the shingles, and this may cause leakage.
30. Interlocking singles. These are separate shingles fastened with one another to create ample resistance toward the wind.
31. Laminated shingles. These are two pieces of shingles attached together via a lamination technique to obtain an increased thickness to the structure. They are also known as architectural and three-dimensional shingles.
32. Lap. This is a surface in which a shingle or rolled roof is overlapped with another during the installation procedure.
33. Mansard roof. This is a type of roofing design where a roof plane positioned in an almost vertical manner connects to another roof plane where the slope is less at the peak. It does not have any gables.
34. Mineral stabilizer. This is something created from limestone which is ground until fine. Other substances like slates and trap rocks can also be used to create mineral stabilizers. These are mixed with asphalt to create a coating to increase the strength and resistance toward fire and harsh weather.
35. Nesting. This is a re-roofing technique where the second layer of new shingles made of asphalt is installed. The upper end of the new shingles is butted at the base end of the existing shingle tab.
36. Pitch. This is a way to show the degree or angle of the inclination of the roof whereby it is displayed in the form of ratio of the rise, calculated in feet.
37. Low Slope. This is a term used to describe a roof pitch that has an angle lower than thirty degrees.
38. Normal Slope. This is the term used to describe a roof pitch angled around 30 – 40 degrees.
39. Steep Slope. This is the term used to describe a roof pitch angled at 45 degrees or higher.
40. Rafter. This is a frame used as a support and it complements the structure of the roof. It is placed right under the deck, and sheathing is nailed right to it.
41. Rake. This is a sloped roof’s edge in an inclined position and applied above a wall starting at the eave and ending at the ridge. The eave and ridge can be positioned closely together or further apart.
42. Ridge. Horizontally angled exterior created from the joint of a couple of roof’s slopping sides and it takes place at the peak of the roof, dormer or hip.
43. Run. This is to show the distance of the eaves from a spot immediately beneath the ridge or 1 ½ the span in a horizontal manner.
44. Selvage. The selvage part of rolled roof overlapping with the roof’s cover and the purpose is to create double coverage.
45. Sheathing. This is a board with external grade utilized as a deck material for the roof.
46. Shed roof. This is an individual roof plane with the absence of hips, roof valleys, gables and ridges. It isn’t connecting to other roofs as well.
47. Slope. This is to show the inclination of the roof in the form of degree and the expression takes place in the form of ratio of the rise, calculated in inches.
48. Smooth surfaced roofing. This is a rolled roof coated with ground talc or mica but not granules.
49. Soffit. Eaves in the form of finished underside and they extend starting at the fascia and ending at the siding, hiding the base of the overhang.
50. Soil stack. This is a vent pipe and it goes deep within the roofing structure.
51. Span. This is to show the distance of one eave to another in a horizontal manner.
52. Specialty eaves flashing membrane. These are self-adhering single underlayment and they are also waterproof. They are created to prevent water infiltration caused by ice dams and rainwater.
53. Starter strip. This refers to asphalt roofing attached to the eaves during the installation of the first batch of shingles.
54. Tab. This is to show the surface of the strip shingles that has been exposed to the weather.
55. Telegraphing. This is a term used to describe the installation of shingles above a surface with valleys and bumps where distortion is visibly present.
56. Truss. This is when beams, ties and bars are combined in the manner of ‘three-in-a-unit’ and truss forms a series of support in the construction of wide span roofs.
57. UL Label. This is the label shown on the packaging to inform the resistance level of asphalt roofing against fire and wind.
58. Underlayment. This is to describe a layer of rolled substances placed beneath the primary roofing substance prior to installing the shingles. The underlayment is made of asphalt and it provides added deck security.
59. Valley. This is to show an interior angle derived from the joint of a couple of inclined surfaces of the roof and the purpose is to allow water runoffs.
59. Vapor barrier or retarder. This can be of any substance as long as it blocks the entrance of water or vapor through it.
60. Vent. This could be any device as long as it is attached to the roof and used as an air outlet. The purpose is to promote better ventilation of the undersides of the roof’s deck.