Edinburgh Napier University

  In order to combat climate change's harmful effects, many steps must be taken to reduce greenhouse gases. Reducing carbon emissions in the construction sector for both new and existing buildings plays a major role in achieving a zero-emissions economy. Reaching zero emissions in existing buildings requires upgrading the building envelope, implementing efficient systems, and then using renewables for the remaining energy requirements. This research suggests a sustainable method for converting an existing residential building into a nearly zero-emission house. In this study, various sustainable scenarios were considered for upgrading an existing house into a nearly zero-emission building. The case study is a house built in 1794, and to reach nearly zero-emission the following steps were applied. First, sustainable strategies for rehabilitating the house were suggested. Secondly, Integrated Environmental Solutions and virtual environment software were used in order to calculate the case study energy and emissions baseline. Thirdly, sustainable materials to upgrade the envelope were considered, as well as identification of alternatives to upgrade the house services. After this, software was used to calculate the effect of each material on energy and emissions reductions in comparison to the baseline. Fourthly, the payback period for each material was calculated by using the total construction costs divided by the revenue from energy savings. Fifthly, alternatives were selected that have reasonable payback periods with regard to the refurbishment process. Finally, renewables were added to cover some of the remaining energy needs. After applying the refurbishment steps the house's energy consumption and emissions reduced significantly. The total cost for the proposed renovation is £24,976.90, with a repayment period ranging between 1.1 and 11.5 years. Energy consumption and carbon emissions are significantly reduced by the addition of renewables when compared to improving the envelope and services. Compared to the baseline, the refurbishment achieves a considerable reduction in energy consumption and emissions by 65.3% % and 62.4% respectively.