jscussel

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Posts posted by jscussel

  1. Joe,

    1. Item 1 - Exposure Category:  What are Conditions B,C & D ?

     

    Exposure A. Large city centers with at least 50 percent of the buildings having a height in excess of 70 feet (21336 mm). Use of this exposure category shall be limited to those areas for which terrain representative of Exposure A prevails in the upwind direction for a distance of at least 0.5 mile (0.8 km) or 10 times the height of the building or other structure, whichever is greater. Possible channeling effects or increased velocity pressures due to the building or structure being located in the wake of adjacent buildings shall be taken into account.


    Exposure B. Urban and suburban areas, wooded areas, or other terrain with numerous closely spaced obstructions having the size of single-family dwellings or larger. Exposure B shall be assumed unless the site meets the definition of another type exposure.


    Exposure C. Open terrain with scattered obstructions, including surface undulations or other irregularities, having heights generally less than 30 feet (9144 mm) extending more than 1,500 feet (457 m) from the building site in any quadrant. This exposure shall also apply to any building located within Exposure B type terrain where the building is directly adjacent to open areas of Exposure C type terrain in any quadrant for a distance of more than 600 feet (183 m). This category includes flat open country, and grasslands.


    Exposure D. Flat, unobstructed areas exposed to wind flowing over open water, including inland waterways, for a distance of at least 1 mile (1.61 km). This exposure shall apply only to those buildings and other structures exposed to the wind coming from over the water. Exposure D extends inland from the shoreline a distance of 1,500 feet (457 m) or 10 times the height of the building or structure, whichever is greater.

     

    Item 2 - Do I need to include the Roof Eave-to Ridge height Adjustment ? Yes

     

    Items 5-7 - Can I skip these Adjustments ? Yes

     

    Does it make sense to have two different programs? In my area, we don't need the seismic adjustment factors. Would this reduce the price?

  2. Lane,

    I use a "Retangular Polyline" with the fill set to "angle Hatch", spacing 6", line weight 50, color white and "transparent pattern background" checked. Been using this method for years.