Things To Know

Roofing Things to Know: 

All roofs with slopes of 25% or more (commonly known to normal humans as steep-slope roof systems) have 5 basic components.

  • Roof Covering: Shingles, tile, slate or metal and underlayment that protect the sheathing from weather.
  • Sheathing:Boards or sheet material that are fastened to roof rafters to cover a house or building.
  • Roof Structure: Rafters and trusses constructed to support the sheathing.
  • Flashing: Pieces of metal or roll roofing used to prevent seepage of water into a building around any intersection or projection in a roof, such as vent pipes, chimneys, adjoining walls, dormers and valleys.
  • Drainage: A roof system’s design features, such as shape, slope and layout that affect its ability to shed water.




There are multiple types of roofing systems; some include asphalt shingles, organic shingles, and fiber glass shingles. To view what we, Adept Construction, specialize in click this link: http://www.excellentroofs.com/roofing/

Roofing depends on personal taste, income, and the structure of your home. So always have an open mind when conversing with your roofing contractor.

Importance of Adequate Ventilation & Insulation

Ventilation and insulation are very important components to any roof system:


  • Vent: 1) Any outlet for air that protrudes through the roof deck, such as a pipe or stack. 2) Any device installed on the roof, gable or soffit for the purpose of ventilating the underside of the roof deck.
  • Collar: Pre-formed flange placed over a vent pipe to seal the roof around the vent pipe opening. Also called a Vent Sleeve.
  • Vent-Top Thermocal: This is a nail base roof insulation with 3/16” venting air space and an APA-rated 7/16” OSB sheathing layer above.

ventlit1.pdf

Ventilation Tips Booklet.pdf

Requirements for proper attic ventilation can vary depending on the area you are located in the United States. So always make sure you are up to date with it and that your contractor knows the proper requirements. Nevertheless, the general ventilation formula is based on the length and width of the attic. NRCA (National Roofing Contractors Association) recommends a mini 1 square foot of free vent area for each 150 square feet of attic floor with vents placed proportionately at the eaves (or soffits) and at or near the ridge.


Roofs Even Have Factors That May Affect Performance 

Even roofs have foes that try to thwart them! They include:


  • SunHeat and ultraviolet rays cause roofing materials to deteriorate over time. Deterioration can occur faster on the sides facing west or south.
  • Rain: When water gets underneath shingles, shakes, or other roofing materials, it can work its way to the roof deck and cause the roof structure to rot. Extra moisture encourages mildew and rot elsewhere in the house, including walls, insulation, or electrical systems.
  • Wind: High winds can lift shingles’ edges (or other roofing materials) and force water and debris underneath them. Extremely high winds can cause extensive damage.
  • Snow/Ice: Melting snow often refreezes at a roof’s overhang where the surface is cooler, forming an ice dam and blocks proper drainage into the gutter. Water backs up under the shingles (or other roofing materials) and seeps into the interior. During the early melt stages, gutters and downspouts can be the first to fill with ice and be damaged beyond repair or even torn off the house or the building.
  • Condensation: Condensation can result from the buildup of relatively warm, moisture-laden air. Moisture in a pocket ventilated attic promotes decay of wood sheathing and rafters, possibly destroying a roof structure. Sufficient attic ventilation can be achieved by installing larger or additional vents and will help alleviate problems because the attic temperature will be closer to the outside air temperature.
  • Moss/Algae: Moss can grow on moist wood shingles and shakes. Once it grows, moss holds even more moisture in a roof system’s surface, causing rot. In addition, moss roots can also work their way into a wood deck and structure. Algae also grows in damp, shaded areas on wood or asphalt shingle roof systems. Besides creating a black-green stain, algae can retain moisture, causing rot and deterioration. Trees and bushes should be trimmed away from homes and buildings to eliminate damp, shaded areas, and gutters should be kept clean to ensure good drainage.
  • Trees/Leaves: Tree branches touching a roof will scratch and gouge roofing materials when the branches are too long and get struct by the wind. Falling branches from overhanging trees can damage, or even puncture, shingles and other roofing materials. Leaves on a roof system’s surface retain moisture and cause rot, and leaves in the gutters block drainage.
  • Missing/Torn Shingles: The key to a roof system’s effectiveness is complete protection. When shingles are missing, or torn off, a roof structure and home or building interior are vulnerable to water damage and rot. The problem is it can lead to nearby shingles being ripped easily or blown away. Missing or torn shingles should be replaced as soon as possible.
  • Shingle Deterioration: When shingles are old and worn out, they curl, split, and lose their waterproofing effective shield. Weakened shingles get easily blown off, torn, or lifted by wind gusts. The end result is structural rot and interior damage. A deteriorated roof system only gets worse over time and it should be replaced as soon as possible.
  • Flashing Deterioration: Many apparent roof leaks really are flashing leaks. Without good, tight flashings around chimneys, vents, skylights, and wall/roof junctions, water can enter a home or building and cause damage to walls, ceilings, insulation, and electrical systems. Flashings should be checked as part of a biannual roof inspection and be regularly cleaned.

Essential Roofing Terms To Understand

And finally, to finish this off, here are terms you should know in regards to roofing:


  • Deck/Sheathing: The surface, installed over the supporting framing members, to which the roofing is applied. Exterior grade boards used as a roof deck material.

  • Drip Edge: A corrosion-resistant, non-staining material used along the eaves and rakes to allow water run-off to drip clear of underlying construction.
  • Eave: The horizontal, lower edge of a sloped roof.

  • Fascia: A wooden board or other flat piece of material such as that covering the ends of rafters.
  • Felt/Underlayment: Organic fiber mat impregnated with asphalt and used as an underlayment beneath roofing to provide additional protection for the deck.

  • Fire Rating: The performance of roof coverings exposed to simulated fire sources originating from outside a building on which the coverings are installed. They are applicable to roof coverings intended for installation on either combustible or non-combustible decks. 

This standard includes three classes of fire exposure: 

• Class A roof coverings, which are effective against severe fire test exposures

• Class B roof coverings, which are effective against moderate fire test exposures  

• Class C roof coverings, which are effective against light fire test exposures. 

Under such exposures, the roof coverings afford a degree of fire protection to the roof deck, do not slip from position, and are not expected to produce flying brands.

  • Flashing: Pieces of metal or roll roofing used to prevent seepage of water into a building around any intersection or projection in a roof, such as vent pipes, chimneys, adjoining walls, dormers and valleys.
  • Louvers: A window blind or shutter with horizontal slats that are angled to admit light and air, but to keep out rain and direct sunshine.

  • Oriented Strand Board (OSB): Non-veneer oriented strand board. A decking made from wood chips and lamination glues.
  • Protrusions: i.e. Pipes and ducts. Anything that passes through the sheathing.
  • Penetrations: Anything that goes through the roof. i.e. Skylights, A/C units, air vents, and plumbing vents, to name a few.
  • Rafters: The supporting framing member immediately beneath the deck, sloping from the ridge to the wall plate.

  • Rake: The inclined edge of a sloped roof over a wall.

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