Recent empirical studies have investigated the impact of noise barriers on housing prices of adjacent homes. Their results have conflicting evidence. One important observation is that the existing literature examines the impact of berm barriers. Missing in this literature is the impact of barriers made out of other materials. This paper investigates the impact of Noise Barrier Walls (made out of other materials) on the market value of adjacent residential homes. We use a data set containing 141 noise barriers built in 12 counties of Washington State, U.S.A. The data on the location of noise barrier walls is obtained from Washington State Department of Transportation (WSDOT), Environmental Service Office (ESO) -Environmental Information Program. Two models are employed, the hedonic price model and a mofied hedonic model in a quasi-random experiment. The modified Hedonic price method results are very impressive: On average, Noise Barrier walls increase prices of residential homes within 300m by 15.24% . This impact decreases as the distance from the noise barriers increases. We estimate an increase in housing prices of 6.96 % more for houses between 300m and 600m away from the noise barrier.