Sri Lankan traditional industries have existed for several centuries, while providing considerable level of employment and livelihood for rural community. Inadequacy of researches pertaining to this sector questions the future existence. In addition, lack of adaptation of latest developments in manufacturing technology and business models too increase the severity of this exacerbating issue. Therefore, industrialists struggle in decision making processes in terms of costing and scaling of environmental impact and social issues. Since the Brass Manufacturing is one of the major traditional industries in Sri Lanka, this research focuses to develop a decision making framework for costing and environmental management aspects which directs towards the sustenance of the industry. The proposed framework is developed based on value Stream mapping and life cycle principles for manufacturing costing tool and environmental impacts assessment. A detail study has been conducted, while closely monitoring the material flow, information flow and decision making methods. This has been utilized for developing the value stream, which reflects the cross section of industry. Life cycle costing procedure is utilized to develop the costing tool. Life cycle impact assessment is carried out using SimaPro, which demonstrates the impacts on the environment. The proposed approach can be adapted for decision making when introducing new designs and products to the market and to promote better environmental practices.