Excess molar volumes of the ternary mixture {x(1) di-n-butylether + x(2) 1-heptanol + (1 - x(1) - x(2)) n-octane} and the corresponding binary mixtures were measured at the temperature 298.15 K. Excess molar volumes were determined using an Anton Paar densimeter. The experimental values were compared with the results obtained with some empirical methods for the estimation of ternary properties from binary results.