Use of solid walls and earth berms as highway noise barriers is becoming more widespread. A survey of the methods generally accepted for use in acoustical evaluation and prediction of barrier performance indicates the following: First, most methods are based on the theory of Maekawa (diffraction by a semi‐infinite screen). Second, the methods are either too complex to use except for final design evaluation, or they are too simplified for use except in preliminary design stage. This paper describes a method developed to bridge this gap. The method is based on the results of Maekawa and involves the analysis of a single truck pass‐by. The vehicle is modeled as three incoherent noise sources representing stack, engine, and tire noise. The attenuation for each octave band is determined; then the octave bands are combined to give anA‐weighted sound level. Evaluation of the effectiveness of the sound wall is done by comparing the noise signature with and without a barrier present. The method is simple enough to allow comparison of many barriers in a short period of time, but complete enough to be considered as accurate as the Maekawa results it is based on. Results from use of the method in the design and analysis of several projects are presented.