Most of road networks are constructed using hot mix asphalt (HMA). HMA is used for roads construction and maintenance at high temperature (150-170˚C) requiring high fuel consumption. In addition, gases emissions generated from HMA are issues of concern among the pavement researchers. Therefore, reducing gases emission and mixing temperature is an objective toward sustainable asphalt pavement industry. Thus, using warm or half-warm asphalt mixes as a modern technique are considered suitable alternatives to HMA. This study aims to reduce gasses emissions and manufacturing cost of HMA using half-warm mixes asphalt (HWMA). Chemical additives are used in order to produce HWMA at low temperature. In this study, Ethoxylated Nonyl Phenol (NP9) was used to enhance the performance of asphalt mixes at low temperature. The tried percentages of NP9 were 10, 15, 20, and 25% (by weight of bitumen). The tested mixes include control mix (mixed at 155°C) and modified mixes (mixed at 90°C ,HWMA modified by NP9). Rolling thin film oven (RTFO), Marshall, moisture susceptibility, indirect tensile strength (ITS), wheel tracking, scanning electron microscopic (SEM) and gases measurements tests were carried out for control and modified mixes. The results indicated that, significant changes were occurred in modified mixes compared to the control mixes. The results revealed that producing HWMA reduced the initial aging and emissions. In addition, adding NP9 to asphalt mixes enhanced the engineering properties of the mixes.