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Weekend Cabin Retreat Project Roofs. Sacramento City College EDT 300 Kenneth Fitzpatrick, P.E. Types of Roofs. The appearance of a house is affected greatly by the roof lines and material. The roof should compliment the structure. Gable Roof. The gable roof is very popular.
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Weekend Cabin Retreat ProjectRoofs Sacramento City College EDT 300 Kenneth Fitzpatrick, P.E. EDT 300 - Cabin Design Project - Roofs
Types of Roofs • The appearance of a house is affected greatly by the roof lines and material. • The roof should compliment the structure. EDT 300 - Cabin Design Project - Roofs
Gable Roof • The gable roof is very popular. • Easy to build. • Sheds water well. • Provides for ventilation. • Can be used on a variety of house designs. EDT 300 - Cabin Design Project - Roofs
Hip Roof • The hip roof is slightly more difficult to build than a gable roof. • The hip roof is a very popular choice. • Doesnotprovide for ventilation as well as gable roof. • Increased chance of leaks because of hips and valleys. EDT 300 - Cabin Design Project - Roofs
Flat Roof • The flat roof is the most economical roof to construct. • Doesn’t add much to the appearance of the house. • Requires “built-up” or membrane roof covering instead of conventional shingles. • A built-up roof consists of layers of roofing felt and tar. • Usually pitched about 1/8” to 1/2” to provide for drainage. EDT 300 - Cabin Design Project - Roofs
Flat Roof • The flat roof is popular in warmer areas of the country where wide overhangs are desirable for shade and where little or no snow falls. EDT 300 - Cabin Design Project - Roofs
Shed Roof • The shed roof is similar to flat roof but has more pitch. • Frequently used for additions to existing buildings. • A built-up roof is often required. • Pitch must be 3:12 to use shingles. EDT 300 - Cabin Design Project - Roofs
Butterfly Roof • The butterfly roof has not been used widely in the past. • Provides plenty of light and ventilation. • Drainage is the problem. • Flashings must extend far up the roof to prevent leaks. EDT 300 - Cabin Design Project - Roofs
Gambrel Roof • The gambrel roof is sometimes called a “barn roof”. • It has been used extensively for barns. • Provides the additional headroom required for the “Dutch colonial” building style. EDT 300 - Cabin Design Project - Roofs
Winged Gable • The winged gable is a variation on the gable roof. • Ridge peaks are extended to form a point. EDT 300 - Cabin Design Project - Roofs
Dutch Hip • The dutch hip is a combinedgable and hip configuration. EDT 300 - Cabin Design Project - Roofs
Mansard Roof • The mansard roof has not been popular for several years. • Is returning to popularity. • Is a French design. • Is more difficult to construct than hip or gable. EDT 300 - Cabin Design Project - Roofs
A-Frame Roof • The A-frame is a combinedwall and roof. • Originally used for cottages. • Now is used for homes, churches, and other structures. EDT 300 - Cabin Design Project - Roofs
Curved Plate Roof • Similar to Folded Plate roof. • Limited residential application. • Some use in prefabricated modules. EDT 300 - Cabin Design Project - Roofs
Folded Plate Roof • The Folded Plate Roof is a contemporary design. • It is finding some limited application in residential construction. • Quite popular for motels and small commercial buildings. • Many modular, prefabricated units have this type of roof. EDT 300 - Cabin Design Project - Roofs
Traditional Frame Roof Construction EDT 300 - Cabin Design Project - Roofs
Rafters • Roof covering material is supported by roof framing. • The framing must be strong and rigid. • Roof framing consists of several distinct structural elements. • The first and most basic of these elements is the rafter. EDT 300 - Cabin Design Project - Roofs
Rafters • Common rafters are perpendicular to the top wall plate. • They extend from the plate or beyond to the ridge of the roof. • Note that several types of rafters other than common rafters are identified. EDT 300 - Cabin Design Project - Roofs
Rafters • Rafters are cut to the proper dimensions by locating the ridge cut, seat cut, plumb cuts, and tail cut. • The precise layout of these cuts is determined by • The slope or pitch of the roof. • The inside width or clear span of the building. EDT 300 - Cabin Design Project - Roofs
Rafters • Terms that must be understood before calculating rafter dimensions and roof pitch are: • Rise. • Run. • Span. EDT 300 - Cabin Design Project - Roofs
Terminology • Rise - the vertical distance measured from the top of the wall plate to the underside of the rafters. EDT 300 - Cabin Design Project - Roofs
Terminology • Run - one-half of the distance of the clear span. EDT 300 - Cabin Design Project - Roofs
Terminology • Clear Span - is the horizontal distance from the inside of one stud wall to the inside of the opposite stud wall. EDT 300 - Cabin Design Project - Roofs
Roof Slope • Roof slope may be indicated on the drawings by: • A slope ratio diagram • A fractional pitch indicator • An angular dimension. • The angular dimension method is seldomused • It is difficult to measure as accurately as either of the other methods. EDT 300 - Cabin Design Project - Roofs
Roof Slope • When designing a roof, use a standard roof pitch. • 3 in 12. • 4 in 12. • 5 in 12. • 6 in 12. EDT 300 - Cabin Design Project - Roofs
Rafters • Select rafters based on • The distance to be spanned. • The spacing of the rafters. • The weight to be supported. • Rafters for low-slope roofs may also serve as ceiling joists. EDT 300 - Cabin Design Project - Roofs
Roof Weights Per Square Foot • A “light roof” is one that weighs less than 4 lbs per square foot. • Examples: • Cedar shake roof. • Composition roof. • Metal roof. EDT 300 - Cabin Design Project - Roofs
Roof Weights Per Square Foot • A “heavy roof” is one that weighs more than than 4 lbs per square foot. • Examples • Slate. • Clay tile. • Concrete tile. EDT 300 - Cabin Design Project - Roofs