Building energy usage has been an important issue in recent decades, and energy prediction models are important tools for analysing this problem. This study provides a comprehensive review of building energy prediction models and uncertainties in the models. First, this paper introduces three types of prediction methods: white-box models, black-box models, and grey-box models. The principles, strengths, shortcomings, and applications of every model are discussed systematically. Second, this paper analyses prediction model uncertainties in terms of human, building, and weather factors. Finally, the research gaps in predicting building energy consumption are summarised in order to guide the optimisation of building energy prediction methods.

This research evaluates the operational heating and cooling energy consumption of cross-laminated timber (CLT) office buildings in China. The evaluations involve a comparison of the energy consumption of a reference RC structure and CLT system office buildings. Computational simulation results are based on IES-VE 2019 and show that the estimated heating energy saving ratio of CLT buildings in Harbin, Beijing, Shanghai, and Kunming to the reference structure are 11.97%, 22.11%, 30.94%, and 23.30% respectively. However, the CLT buildings consume more energy for cooling in the summer. The results of the research show significantly higher heating energy reductions for CLT buildings in the Cold Region and Severe Cold Regions of China. Thus, the application of the CLT system is better suited to northern China than southern China. The results of the research can be used in further assessment of the use of CLT systems in different climatic regions in China.

Many stadiums will be built in China in the next few decades due to increasing public interest in physical exercise and the incentive policies issued by the government under its National Fitness Program. This paper investigates the energy saving and carbon reduction performance of timber stadiums in China in comparison with stadiums constructed using conventional building materials, based on both life cycle energy assessment (LCEA) and life cycle carbon assessment (LCCA). The authors select five representative cities in five climate zones in China as the simulation environment, simulate energy use in the operation phase of stadiums constructed from reinforced concrete (RC) and timber, and compare the RC and timber stadiums in terms of their life cycle energy consumption and carbon emissions. The LCEA results reveal that the energy saving potential afforded by timber stadiums is 11.05%, 12.14%, 8.15%, 4.61% and 4.62% lower than those of RC buildings in “severely cold,” “cold,” “hot summer, cold winter,” “hot summer, warm winter,” and “temperate” regions, respectively. The LCCA results demonstrate that the carbon emissions of timber stadiums are 15.85%, 15.86%, 18.88%, 19.22% and 22.47% lower than those of RC buildings for the regions above, respectively. This demonstrates that in China, timber stadiums have better energy conservation and carbon reduction potential than RC stadiums, based on life cycle assessment. Thus, policy makers are advised to encourage the promotion of timber stadiums in China to achieve the goal of sustainable energy development for public buildings.

In recent decades, the issue of building energy usage has become increasingly significant, and U-values for building envelopes have been key parameters in predicting building energy consumption. This study comprehensively reviews the U-values (thermal transmittances) of building envelopes made from conventional and bio-based materials. First, it introduces existing studies related to the theoretical and measured U-values for four types of building envelopes: concrete, brick, timber, and straw bale envelopes. Compared with concrete and brick envelopes, timber and straw bale envelopes have lower U-values. The differences between the measured and theoretical U-values of timber and straw bale envelopes are minor. The theoretical U-values of concrete and brick envelopes ranged from 0.12 to 2.09 W/m²K, and the measured U-values of concrete and brick envelopes ranged from 0.14 to 5.45 W/m²K. The theoretical U-values of timber and straw bale envelopes ranged from 0.092 to 1.10 W/m²K, and the measured U-values of timber and straw bale envelopes ranged from 0.04 to 1.30 W/m²K. Second, this paper analyses the environmental factors influencing U-values, including temperature, relative humidity, and solar radiation. Third, the relationship between U-values and building energy consumption is also analysed. Finally, the theoretical and measured U-values of different envelopes are compared. Three research findings in U-values for building envelopes are summarised: (1) the relationship between environmental factors and U-values needs to be studied in detail; (2) the gaps between theoretical and measured U-values are significant, especially for concrete and brick envelopes; (3) the accuracy of both theoretical and the measured U-values needs to be verified.

The aims of the paper were to clarify whether office buildings in the severe cold and cold regions are overheating, especially those with natural ventilation, and whether potential overheating is related to the building materials. The severe cold and cold regions of China were considered to be cool regions during summer. However, with global warming, improvements in the thermal performance of the building envelope and the urban heat island effect, office buildings in these regions are showing different degrees of overheating during summer. Two office building materials commonly used in this area, cross laminated timber (CLT) and concrete block, were simulated in this study. With reference to the overheating standard, the degree of overheating in six cities in the severe cold and cold regions was quantitatively analysed and the extent of overheating for the two building materials was compared. Finally, the influence of thermal insulation on building overheating is discussed, and some suggestions are put forward to improve the relevant national regulations in China. The results show that office buildings in the severe cold and cold regions experience overheating during summer, and CLT buildings are more prone to overheating than concrete buildings during summer. This is attributable to the different thermal mass of the materials. Thick insulation does increase the risk of building overheating, and the effect on concrete buildings is more pronounced. Concrete buildings with an insulation layer can experience overheating for 27–71 h more than buildings without an insulation layer. Insulation on CLT buildings only results in an increase of 11–37 h. When considering the current situation with summer overheating in the severe cold and cold regions, relevant codes should also be modified and improved accordingly to guide building design, so as to achieve low-carbon and energy-saving goals.