Virtual design tools and methods can aid in creating decision bases, but it is a challenge to balance all the trade-offs between different disciplines in building design. Optimization methods are at hand, but the question is how to connect and coordinate the updating of the domain models of each discipline and centralize the product definition into one source instead of having several unconnected product definitions. Building information modelling (BIM) features the idea of centralizing the product definition to a BIM-model and creating interoperability between models from different domains and previous research reports on different applications in a number of fields within construction. Recent research features BIM-based optimization, but there is still a question of knowing how to design a BIM-based process using neutral file formats to enable multidisciplinary optimization of life-cycle energy and cost. This paper proposes a framework for neutral BIM-based multidisciplinary optimization. The framework consists of (1) a centralized master model, from which different discipline-specific domain models are generated and evaluated; and (2) an optimization algorithm controlling the optimization loop. Based on the proposed framework, a prototype was developed and used in a case study of a Swedish multifamily residential building to test the framework’s applicability in generating and optimizing multiple models based on the BIM-model. The prototype was developed to enhance the building’s sustainability performance by optimizing the trade-off between the building’s life-cycle energy (LCE) and life-cycle cost (LCC) when choosing material for the envelope. The results of the case study demonstrated the applicability of the framework and prototype in optimizing the trade-off between conflicting objectives, such as LCE and LCC, during the design process.

The development of high-rise buildings worldwide has given rise to significant concerns regarding their excessive electricity consumption. Among the various categories of high-rise structures, hotels used for business and conferences stand out as particularly extravagant in their energy use. The consequence arising from excessive energy usage is an escalation in carbon emissions, which is a primary driver of global warming. Therefore, this study aims to investigate the energy use intensity (EUI) of a hotel building located in Jakarta, Indonesia. In order to improve energy performance, this study explored various options for renovating the building envelope, such as incorporating insulation and a roof covering, as well as implementing building-integrated photovoltaics (BIPV). The building envelope renovations demonstrated a notable reduction in energy use by 15.8–27.7% per year. BIPV, such as curtain walls and double-skin façades, generated an energy use reduction of 4.8–8.6% per year. Remarkably, by combining the two approaches (i.e., adding insulation and a roof covering in the building envelope and adopting BIPV as double-skin façades), the potential reduction in energy use reached up to 32.2% per year. The findings can assist decision-makers in developing building renovation strategies for high-rise buildings while considering energy conservation.

Building developers are continuously seeking solutions to increase saleable/rentable floor area and thus the profitability of investments, especially in large/dense cities where the real estate/rental values are high and shortage of available land results in smaller building footprints. Application of passive energy efficiency measures (e.g., thick insulation in walls) not only affects the life cycle sustainability of buildings, but also the floor area and its profitability. This can affect the decisions made on the choice of measures when aiming to improve sustainability. In line with limited studies in this context, a case study is presented here in which multi-objective optimization was used to explore the impact of various passive energy efficiency measures on the life cycle sustainability when accounting for the profitability of the floor area. The building case was a high-rise apartment based on a standardized building concept situated in different locations in Sweden, namely Vindeln, Gothenburg, and Stockholm. The findings indicated that, regardless of the location, use of (1) thick cellulose coating for the roof, and (2) moderately thick expanded polystyrene for the floor, were necessary to improve the life cycle sustainability. However, the optimal wall insulation was dependent on the location; in locations with high real estate values, the scope for using thick and conventional insulations (mineral wool/cellulose) was limited due to the significant economic loss caused by floor area reductions. In general, the optimization identified optimal solutions that could save up to 1410.7 GJ energy, 23 tonnes CO₂e, and 248.4 TEUR cost from a life cycle perspective relative to the building’s initial design.