Studies of Davenport and others have provided the basis for a simple gust factor approach to evaluate the wind-induced structural responses. This approach is based on the maximum responses that can be represented by their corresponding mean maximum response. However, the uncertainty in the wind characteristics and in the material properties and geometry variables affects not only the mean maximum responses but also their variability. By considering these uncertainties, estimates of the statistics of the maximum responses can be obtained from the unconditional probability distributions of the maximum responses. Alternatively, they can be obtained directly from the uncertainty propagation analysis based on the conditional mean maximum responses. The former is accurate whereas the latter is an approximation. The adequacy of this approximation and its effect on the structural reliability are investigated. Results reported in this study seem to support that the use of the conditional maximum response equal to the mean maximum response is adequate for the uncertainty propagation analysis. Results of the reliability analyses also suggest that the consideration of the uncertainty in structural parameters such as the fundamental period of vibration and the damping ratio is very important for serviceability limit states, and that these uncertainties may be ignored for the resistance based limit states as long as the structure behaves linearly.