Inspecting Roofs Part 2

Common Types of Roof shingles Asphalt (composition) shingles Largest market share Low cost & acceptable life span Slate shingles Hard, dense stonel (last 75 years or more if well constructed)) Clay & concrete tile Wood shingles & shakes Once extensively used, but less so now due to fire hazard Metal shingles Variety of colors and finishes Small market share

Typical valley and roof detail of underlayment

Typical Valley Treatments (Shingles) Types Open valley Exposed to view Provides smooth and rapid discharge of water Woven valley (closed valley) More layers of roofing, more durable than open valley Closed-cut valley (combination open and woven) Resistant to roof traffic Most commonly used

Open-valley flashing: rolled roofing

Open-valley: Sheet metal flashing

Woven valley

Closed-cut valley

Ridge and hip conditions Ridge and hip conditions occur where two sloping roofs meet Water sheds away from ridge Type of shingle (ridge cap) Special ridge shingle Fabricated from standard shingle

Ridge caps from standard shingle

Ridge caps on hip roof

Drip-edge (perimeter flashing)

Step flashing where sloped roof meets vertical wall

Flashing at chimney: Apron flashing at low side

Flashing at chimney: step flashing at sidewalls

Wood Shingles & Shakes (sawn) (hand split) Installed over solid or spaced plank sheathing Interlayment (felt) is laid in between each course. Some curling & lifting with wet/dry changes is normal. Inspection from INSIDE is critical—leakage will show there

Wood Shingles & Shakes Typical Problems: Rot and deterioration Loose or missing pieces Mildew/moss Water penetration

General Roof Reporting Methods Identify: Type & approximate age (ask homeowner) Number of layers Condition: Satisfactory = roof covering will last over 5 yrs Marginal = less than 5 yrs life remaining Poor = replace soon (major repairs required)