Alpine

Framing with Trusses Hip Framing Roof Truss Span Tables Terminal Hip Framing Best suited for relatively short spans of 26'-0" or less, the hip jacks extend directly to the peak. The distance from the end wall to the face of the girder is equal to one half the span, provided the slopes are equal. The last standard truss is designed as a girder to carry the loads transferred by the hip jack. Step Down Hip Framing Better suited for longer spans, the Step Down hip is the most versatile of all hip types. Each of the "step down" trusses is the same span and has the same overhang as the adjacent standard trusses, but decrease in height to form the end slope. The girder location is generally from 8 to 12 feet from the end wall and is determined by the span to depth ratio. The corner and end jacks are normally pre-built components. Truss designs are engineered to meet specific span, configuration and load conditions. The shapes and spans shown here represent only a fraction of the millions of designs produced by ITW Building Components Group. Total load(PSF) Duration factor Common -- Truss configurations for the most widely designed roof shapes. Trussed hip framing offers the advantage of clear span, an eave or fascia line at the same elevation around the building, and the speed of pre-built components. The end slope may be equal to or different from the side slope. The ceiling line may be flat or sloped. Sloped ceilings have limitations, therefore, consult the truss designer. Pitch Mono -- Used where the roof is required to slope only in one direction. Also in pairs with their high ends abutting on extremely long spans with a support underneath the high end. Scissors -- Provides a cathedral or vaulted ceiling. Most economical when the difference in slope between the top and bottom chords is at least 3/12 or the bottom chord pitch is no more than half the top chord pitch. Live load(PSF) Roof type 55 1.15 47 1.15 40 1.15 40 1.25 40 snow shingle 30 snow shingle 20 snow shingle 20 ** shingle 55 1.15 6" **construction or rain, not snow load 30 snow tile Top Chord Bottom Chord 12' 2x4 2x4 2x6 2x6 2x4 2x6 2x4 2x6 2x6 2x4 2x4 2x6 2x4 2x6 2x6 2x4 2x4 2x6 2x4 2x6 2x6 2x4 2x4 2x6 2/12 2.5/12 3/12 3.5/12 4/12 5/12 6/12 7/12 24 29 34 39 41 44 46 47 24 29 34 39 43 52 60* 67* 33 39 46 53 59 67* 69* 70* 27 33 37 41 43 46 47 48* 27 33 39 44 49 58 67* 72* 37 45 53 61 64 69* 71* 72* 31 37 40 44 46 49 51 52* 31 38 44 50 56 66 74* 77* 43 52 60 65 69 74* 76* 77* 33 39 43 47 49 53 55 56* 33 40 46 52 57 66 74* 80* 46 55 64 70 74 80* 82* 83* 2/12 2.5/12 3/12 3.5/12 4/12 5/12 24 28 30 33 35 38* 24 29 33 37 41 47* 33 40 45 49* 52* 57* 25 29 31 34 36 39* 27 32 37 41 45* 51* 38 43 47 51* 54* 59* 27 31 34 36 39 42* 31 37 42 46 50* 56* 41 46 50 54* 58* 63* 29 33 36 39 42* 45* 32 37 42 46 49* 54* 44 49 54 58* 62* 68* 6/12 - 2/12 ‡ 6/12 - 2.5/12 ‡ 6/12 - 3/12 ‡ 6/12 - 3.5/12 ‡ 6/12 - 4/12 ‡ 40 37 33 28 22 43 38 33 28 22 59* 52 45 38 31 42 38 35 32 26 49 44 38 32 26 62* 57* 52 44 36 45 41 38 34 30 56* 50 43 37 30 66 61* 56* 50 41 48 44 40 36 32 57* 52 46 39 32 71* 66* 60* 54 44 Spans in feet to out of bearing ‡ Other pitch combinations available with these spans For Example, a 5/12 - 2/12 combination has approx. the same allowable span as a 6/12 - 3/12 Midwest Hip Framing Flat -- The most economical flat truss for a roof is provided when the depth of the truss in inches is approximately equal to 7% of the span in inches. The Midwest type hip framing was developed to create a more uniform configuration of each of the trusses in the hip. This hip type also provides for a more uniform structure for attaching the decking. Span capability is the same as the step down hip. Total load(PSF) Duration factor Live load(PSF) Top Chord Bottom Chord 55 1.15 47 1.15 40 1.15 40 1.25 40 snow 30 snow 20 snow 20 rain or constn. 2x4 2x4 2x6 2x6 2x4 2x6 23 25 27 29 32 33 34 36 39 40 44 45 24 27 28 30 32 33 34 36 39 42 47 51 Depth 16" 18" 20" 24" 28" 30" 32" 36" 42" 48" 60" 72" California Hip Framing Although this type hip framing is used as an alternative to the step down hip, the California hip is similar in span capability and field installation. The base portion of each truss inside the girder is the same, except that the sloping top chord of each successive truss is extended upward greater amounts to form the slope intersection. Corner and end jacks are used to form the area outside the girder. 4 www.itwbcg.com 2x4 2x6 2x6 2x4 2x4 2x6 2x4 2x6 2x6 2x4 2x4 2x6 2x4 2x6 2x6 2x4 2x4 2x6 Spans in feet to out of bearing 25 § 28 30 33 36 38 39 42 45 49 55 60 25 § 27 28 31 34 35 36 39 41 43 46 48 25 § 27 28 31 33 35 36 38 41 44 49 54 25 § 29 § 32 35 39 40 42 45 48 52 58 64 25 § 29 § 31 34 37 38 39 42 44 46 48 51 25 § 29 § 30 33 36 37 39 41 44 47 53 57 25 § 29 § 33 § 38 42 44 45 48 52 56 63 68 25 § 29 § 32 35 38 40 41 43 45 46 49 51 25 § 29 § 31 34 37 39 40 43 46 49 55 59 25 § 29 § 33 § 40 44 45 47 50 54 58 65 69 § = Span Limited by length to depth ratio of 24 NOTES: These overall spans are based on NDS '01 with 4" nominal bearing each end, 24" o.c. spacing, a live load deflection limited to L/240 maximum and use lumber properties as follows: 2x4 fb =2000 psi ft=1100 psi E=1.8x106 2x6fb=1750 psi ft=950 psi fc=1900 psi E=1.8x106. Allowable spans for 2x4 top chord trusses using sheathing other than plywood (e.g. spaced sheathing or 1x boards) may be reduced slightly. Trusses must be designed for any special loading such as concentrated loads from hanging partitions or air conditioning units, and snow loads caused by drifting near parapet or slide-off from higher roofs. To achieve maximum indicated spans, trusses may require six or more panels. Trusses with an asterisk (*) that exceed 14' in height may be shipped in two pieces. Contact your truss manufacturer for more information. 9

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