Coastal and Floodplain Construction Inspector's Practice Exam

What is the uplift value for a building with a roof and ceiling dead load of 20 psf in a 100 mph wind zone with stud spacing of 24" o.c.?

1. 600 lbs per stud

2. 545 lbs per stud

3. 500 lbs per stud

4. 480 lbs per stud

The correct answer is: 545 lbs per stud

To determine the uplift value for a building in a specific wind zone, it’s essential to consider both the dead load of the roof and ceiling and the wind uplift forces acting on the structure. In this case, we start by calculating the wind uplift using the appropriate formula, which usually factors in the wind speed and building characteristics. The uplift force can be calculated using the formula: \[ \text{Uplift} = \frac{W \times C}\text{spacing} \] Where: - \(W\) is the dead load (20 psf in this scenario), - \(C\) is the wind uplift pressure derived from the wind speed (which for a 100 mph zone can typically be estimated), - spacing refers to the stud spacing (24 inches or 2 feet). For a wind speed of 100 mph, the uplift pressure can be roughly calculated as follows: 1. The basic wind speed translates into a wind uplift pressure that is typically around 0.6 times the square of the wind speed in miles per hour, though specific codes may vary. For instance, if wind pressure for 100 mph is approximated as in the range of 30 to 35 psf. 2. Using a general