You can lower the possibility of damage to your roof by knowing something about the anatomy.  Being aware of what each component in the roof system does can help you decide which ones to include the next time you re-roof.  In fact, once you know what the possibilities are, there might be a change or two that you'll want to make to your existing roof.  This will help you understand how your roof will be completed.

Chimney Flashing  (#1)
 The material placed around a chimney for waterproofing the roof penetration.

Vent Pipe Flashing  (#2)
A small pipe that extends from plumbing fixtures to a vent stack in the roof, allowing sewer gases to escape to the outer air.

Shingles  (#3)
A thin oblong piece of material, such as wood or slate, that is laid in overlapping rows to cover the roof or sides of a house or other building.

Felt Underlayment  (#4)
Asphalt saturated felt used beneath roofing to provide additional protection from the deck.

Ridge Board  (#6)
Horizontal board that serves as a support in the highest point of the roof structure.

Rafter  (#7)
The structural members that support the roof.

Collar Beam  (#8)
Wood members connecting opposite roof rafters. They serve to strengthen the roof structure.

Valley Flashing  (#9)
Sheet metal that lays in the "V" area of a roof valley.

Valley Underlayment  (#10)
Holds the materials in place.

Fascia  (#12)
The vertical boards nailed to the lower ends of rafters.

Rake  (#14)
A board or molding placed along the sloping sides of a frame gable to cover the ends of the siding.

Ridge Board  (#15)
The horizontal board along the line of the ridge - normally along the top of the rafters or trusses.

Down Spout  (#16)
Sometimes called "leaders," are used to direct the water leaving the gutters down to the ground or drainage system in a controlled fashion.

Splash Block  (#17)
A masonry section placed under leader pipe to divert water drainage away from the foundation of a house.

Gutter  (#18)
The exterior drainage system of your home