FLOW SENSOR 1050124 - Caterpillar

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Verify Roof Zone or Edge Zones.Depending on building characteristic, the wind speed will increase, particularly at building edges. When wind is deflected by an object such as a roof, it imparts a force against that structural object. The more it is deflected, the more force it imparts. Maximum force is generated by wind striking a vertical surface perpendicular to the wind. With this in mind, it is not too hard to conclude that the steeper the pitch of the roof the more force that is directed against it.Most of the Structural Engineering and Construction Association adopted the “Roof Zone” method to describe the wind uplift rating. As shown in diagram below, and based on Figure 6-3 of ASCE/SEI 7-05, every roof plane can be separated into interior (Zone 1), edge (Zone 2), or corner (Zone 3) roof zones. The area in each roof zone is determined by calculating the width of the pressure coefficient zone.
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Roof Zone Plan (1½:12 Roof Pitch or Less)
(8) Zone II - Medium Load Wind Zones Around Perimeter (Approx. 15% Of Total Roof Surface.)
(9) Zone I - Lowest Load On Main Field Of The Roof (Approx. 80% Of Total Roof Surface.)
(10) Zone III - Highest Load Wind Zones Here At Each Corner Of The Roof (Approx. 5% Of Total Roof Surface.)
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Source: ASCE/SEI 7-05 Fig 6–3
(A) Flat Roof
(B) Hip Roof
(C) Gable Roof
(D) Gable Roof
(E) Interior Roof Zones - Zone 1
(F) End Roof Zones - Zone 2
(G) Corner Roof Zones - Zone 3Pressure Effects and Roof Zones InterpretationAn example of design pressures for enclosed buildings assuming the same speed of 90 mph, exposure B, and 30 ft roof height. The pressure at Zone 1, 2 and 3 will vary based on the roof type and slope. (Source: http://www.wbdg.org/)
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Flat or Gable Roof, up to 7° roof slope, no overhang
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Gable > 27° to 45° roof slope, overhang all side
(11) -27 psf at perimeter, corners, and ridge line
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Hip or Gable > 7° to 27° roof slope, overhang all side
(12) -46 psf at corners
(13) -23 psf at hip and ridge lines
(14) -27 psf at perimeterWind Loads: could be determined based on ASCE 7 (US Standard), Euro code 1 (EU Code), Wind Code 2004 (Hong Kong Code), GB 50009 (China PR Standard), AS/NZS 1170.2 (Australia/NZ Standard), or other national/international standards/codes.8. Confirm Loading Conditionsa. Confirm load distribution and building structural framing to support weight. Depending on the site conditions, local building codes may also specify a maximum dead load distribution for the roof. Building codes usually allow dead loads of no more than 5 lb per square foot of roof space. Fortunately, most racking products and modules add only about 3 lb per square foot. To compute the dead load of the array, divide the total weight of the racking, mounts, and modules by the square footage the array will occupy.b. Confirm mounts (standoffs or stanchions) distance. As mentioned before, each manufacturer has its own recommendations for maximum rail span wind speeds. Consult the product literature determine