Roofing 101

#90 Rolled Roofing– Composed of a rolled roofing material with a felt or fiberglass base that is top coated with granules. #90 is used as an under sheet in the installation of closed valleys.

Beauty Course – Comprised of an additional layer of shingles that work to cover the headwall flashing, which is costly and difficult to replace.

Box Vent – Consists of a type of roof vent that is installed near the peak of the roof and allows hot air and moisture to exit.

Decking– Decking is the wood sheeting material that the roofing products are nailed to. There are two different types of decking, sheet decking and slot decking. Sheet decking consists of 4×8-foot sheets and slot decking consists of a series of smaller pieces (1×6 in or 1×8 in) of wood with gaps between them. Modern building codes only allow for sheet decking; however, some older homes may have gapped decking.

Drip Edge– Refers to the metal flashing that is installed around the perimeter of the house on the rake and eave. Drip edge helps prevent water penetration from wind driven rain and water wicking when water drips off the shingles. Most drip edges come in a shiny galvanized metal finish, but they are also available in a handful of pre-painted color finishes. To insure a clean and finished look, we often prefer to utilize the pre-painted drip edges.

Eave – The lowest horizontal edge of a sloped roof that extends beyond the exterior wall.

EPDM– A single ply synthetic rubber roofing membrane used on low slope roofing.

Gable – The upper portion of a sidewall where the rake comes to a triangular point at the ridge of a sloped roof.

Ice and Water Shield – This is part of the underlayment system and is applied before the shingles go on. Ice and water shield is thicker than roofing felt and has a tacky quality which allows it to self-seal when nails penetrate through it. Ice and water shield should be used on any part of the roof that may encounter excessive moisture and any areas that have a potential for water penetration or ice damming. We recommend installing ice and water shield on all eaves, in valleys around skylights, swamp coolers, chimneys and many other roofing components.

Modified Bitumen– Heavy roofing material that are utilized on low slope applications. It is made up of asphalt and a variety of rubber modifiers. The exposed top section is granulated and comes in a variety of colors.

OSB – The most commonly used roof decking material. Manufactured in 4 foot by 8-foot Sheets.

Pipe Jack – Consists of a flashing boot that is installed over the plumbing vents that infiltrate the roof, in turn creating a weather tight seal. Over time, the sun can dry out the rubber in the boot and the metal can start to form rust. This is why we will always replace the pipe jacks on every roof we install.

Rain Cap– Rain Caps are utilized to cover any exhaust vents that penetrate the roof. They allow exhaust gases to escape while preventing water from entering the exhaust pipe. It is very common for rain caps to get damaged by hail, but it is necessary for them to get fixed correctly due to the idea that a crushed exhaust cap can prevent the exhaust gases from properly venting out of the house.

Rake – The inclined edge of a sloped roof over a wall from the eave to the ridge.
Re-Decking– This terms works in reference to the process of installing new 4×8-foot sheets of OSB to the rafters in order to comply with new building codes or the manufactures specifications.

Replacing Decking – There are times when we will tear off the old roofing and find that some of the existing roof decking is in bad shape due to moisture exposure and or excessive heat. To comply with building code these individual sheets must be removed and replaced.

Ridge– The uppermost, horizontal, external angle formed by the intersection of two sloping roof planes.

Ridge Vent– A type of roof vent that is installed directly at the peak of the roof. Ridge vents are low profile and highly effective in providing ventilation within the attic space. There are several instances in which ridge venting is the optimal form of ventilation.

Roofing Felt – Serves as the roofs second layer of protection and is installed on the roof decking before the shingles are applied. The two common forms of roofing felt include #15 and #30. The differences between the two felts are their thickness. The #30 felt is twice as thick as the #15.

Soffit– The finished underside of the eaves.

Soffit Vent – Soffit vents allow fresh cool air to enter the attic space and allow the hot moist air to escape through the roof vents. They are made up of the air intake in the attic ventilation system and are located in the soffit.

Step flashing – Made up of a metal flashing that is installed when a sloped section of a roof runs along a side wall. Step flashing is installed behind the siding and under the shingle; however, there is a 1 to 2-inch section of the flashing that is commonly exposed. Step flashing also comes in a shiny galvanized metal finish as well as a handful of pre-painted color finishes. With this product, we tend to work with the pre-painted step flashing that matches with the shingle color. This effect again insures a clean and professional finished look.

Storm Collar– The Storm Collar is a flashing piece that is installed where the exhaust jack connects with the exhaust pipe. It assures a tight fit and prevents wind driven rain or built up snow from penetrating the roof. We will install a new storm collar if the old one is missing or if we find any damage to the existing one.

Valley – Made when two different roof slopes intersect one another, in turn creating a channel. For some products, there are two options on a valley. You either have the open valley, where there is an exposed metal flashing in the center, or you will have a closed valley, a valley in which the shingles extend further than the valley itself and create a natural channel.