For ON dwellings near the 6 lane freeway, nighttime SPLs were estimated using the US Traffic Noise Model (FHWA, 1998) and CadnaA software (DataKustik GmbHV R, 2014). A speed of 105km per hour was used for heavy trucks as this value is controlled by a speed limiter (Ontario Highway Traffic Act, 2011). For cars, not a dominant noise source, a speed of 120km per hour was used as a reasonable worst case. A concrete road surface was used with 78% of the traffic volume during the day, and 10% of that daytime traffic made up of heavy trucks. The evening was assumed to have 10.8% of the traffic volume of which 15% was assumed to be heavy trucks. Heavy trucks were assumed to make up one quarter of the nighttime traffic volume. As actual values were not known, Austrian values were used as implemented by DataKustik GmbHV R (2014).