Sustainable, nearly zero emissions retrofit for a pre-1919 house in Scotland

To mitigate the adverse effects of climate change, several measures must be implemented to reduce greenhouse gas emissions. Reducing carbon emissions in the construction sector for both new and existing buildings plays a significant role in achieving a zero-emissions economy. Achieving zero emissions in existing buildings requires upgrading the building envelope, implementing efficient systems, and then utilising renewable energy sources to meet the remaining energy requirements. This research proposes a sustainable approach for converting an existing residential building into a nearly zero-emission home. The case study is a house built in 1794, and to achieve nearly zero emissions, the following steps were implemented. First, sustainable strategies for rehabilitating the house were suggested. Secondly, Integrated Environmental Solutions and virtual environment software were utilised to calculate the case study's energy and emissions baseline. Thirdly, sustainable materials for upgrading the envelope were considered, as well as identifying alternatives to upgrade the house's 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 of the proposed renovation is £26,242, with a repayment period ranging from 0.8 to 9.7 years. Energy consumption and carbon emissions are significantly reduced by the addition of renewables compared to improvements in the envelope and services. Compared to the baseline, the refurbishment achieves a considerable reduction in energy consumption and emissions of 65.3% and 62.4%, respectively