Low Energy Buildings Research Articles

A Study on Fire Retardant and Soundproof Properties of Stainless Steel EAF Reducing Slag Applied to Fiber Reinforced Cement Boards.

In recent years, cases of the improper utilization of steel furnace slag have been widely reported, resulting in a crisis of nowhere for recycled resources such as inorganic slag. The misplacement of resource materials that originally had sustainable-use value not only has a great impact on society and the environment but also greatly reduces industrial competitiveness. To solve the dilemma of steel furnace-slag reuse, it is critical to find solutions to the stabilization of steelmaking slag under the innovative thinking of the circular economy. In addition to enhancing the reuse value of recycled resources, the balance between economic development and environmental impact is also crucial. The high-performance building material could provide a solution based on a high-value market. With the development of society and the increasing requirements for quality of life, the requirements for the soundproof and fireproof performance of lightweight decorative panels common in cities have gradually become popular. Therefore, the high performance of fire retardant and soundproofing could be the main development focus of high-value building materials to ensure circular economic feasibility. This study continues the research results of the application of inorganic re-cycled engineering materials in recent years, and the application of electric-arc furnace (EAF)-reducing slag to the development of base materials for reinforced cement boards, in order to complete the development of high-value panels with fireproof and sound-insulation properties in line with the engineering characteristics of the boards. The research results showed the optimization of the proportions of the cement boards with EAF-reducing slag as a raw material. The proportions of EAF-reducing slag to fly ash at ratios of 70:30 and 60:40 all met the requirements of ISO 5660-1 Class I flame resistance; the sound transmission loss in the overall frequency band can reach more than 30 dB, which is higher by 3-8 dB or more than the same board with similar specifications (such as 12 mm gypsum board) in the present building-materials market The products could be developed into building partitions and ceiling decoration boards with high performance in terms of fire retardant and soundproofing values, and also reduce the use of natural raw materials by more than 35%. The results of this study could meet environmental compatibility targets and contribute towards greener buildings. This model of circular economics would achieve energy reduction, emissions reductions, and be environmentally friendly.

Development of a high-performance building material using wood-based corrugated panels manufactured via cold-forming technique

A wood-based sandwich panel with a corrugated core was developed as a building material. A matched-die mold manufactured from commercial plywood was used to fabricate the corrugated panels through a cold-forming process. A cold-setting resin was applied on southern yellow pine (Pinus spp.) veneers with an average thickness of 4 mm, and four plies of them were formed into a corrugated geometry using a wooden mold. When the resin was cured, the corrugated panel of veneers retained the corrugated shape after load removal. Facesheets of the sandwich structures were fabricated using three plies of the same veneers. To evaluate the effect of this corrugated geometry on the structural performance, the same veneers — regarding number, thickness, and orientation — used for the sandwich panel were adopted to fabricate laminated flat panels. Both sandwich and laminated flat panels were submitted to a four-point bending test. The results confirmed the sandwich effect, i.e. a 1741% increase in the bending stiffness of sandwich panels compared to that of laminated flat panels. Sandwich panels developed in this study were compared to Structural Insulated Panels (SIPs), wood-framed structures known as stud walls, and sandwich panels produced using a hot-pressing technique. The cold-formed sandwich panels had higher structural performance than commercial building materials.

On the forecast control of heating system as an easily applicable measure to increase energy efficiency in existing buildings: Long term field evaluation

The priority for reaching carbon neutral buildings by 2050 is to first increase energy efficiency in existing buildings by use of easily and widely applicable measures that are verified based on long-term field research. One such solution is a forecast control of heating systems, which can be quickly and easily integrated to existing weather based controls. However, there are still no long-term field evaluation and detailed analyses of the main features of such a system, which would provide a clear picture about the system’s energetical and economical features and thus increase their wide application in existing buildings. This paper provides the data from a long term field evaluation of an innovative forecast control of heating systems (forHEAT), which can be easily installed (in less than 2 h) and integrated with existing installations in millions of existing buildings in Europe and throughout the world. The energy consumption for heating was evaluated in seven residential buildings and three public office buildings before and after the installation and use of the forecast control. The resulting energy savings averaged 13.4% in the residential and 10.7% in the public buildings located in continental European climate, with very cold winters. The payback time averaged a 0.6 heating season and in most case studies does not exceed a single heating season.

Optimisation of energy consumption using building information modelling technology

The energy consumption of the whole life cycle of the existing buildings in China exceeds 50% of the total energy consumption of the society. With the rapid development of the construction industry, this proportion is still growing. On the whole, there is a lack of analysis of the factors related to energy consumption and comfort in the process of building scheme design at this stage. In addition, designers have insufficient understanding of the theoretical system of low-energy buildings, and it is difficult to optimise the scheme throughout the design. To solve these problems, this research first proposes an integrated design method of green buildings based on building information modelling technology. This method integrates and shares engineering information, problem solving, simulation tools, architectural model applications and architectural team communication platforms, which can effectively address the problem that the current green building projects do not belong to each other when designing. The research also proposes a multi-objective optimisation algorithm based on the genetic algorithm. The proposed method optimises the overall design of green buildings, particularly the design of natural lighting, starting from the influence relationship between targets and targets and between targets and enclosure systems. To obtain the optimal effect, the virtual function of Traind was selected as the training function after testing. In addition, the model obtained a reasonable range of design parameters according to the energy consumption of the building in the uncomfortable time. Finally, the method proposed in the study was tested. The experimental results showed that compared with the overall energy consumption of the initial scheme, that of the optimised scheme was reduced by 10.46%; the natural light coefficient increased by 0.44%; and the pressure differeces pascal hours (PDPH) was optimised by 5.38%. The optimisation scheme can effectively reduce the energy consumption of the building in the whole life cycle and improve comfort.

Durability of humidity-based ventilation components after 13 years of operation in French residential buildings – Assessment of components performance in laboratory

Humidity-based DCV systems have been widely used in France for 35 years and are considered as a reference system, including for low-energy residential buildings. The on-going “Performance 2” project delivers feedback from 13 years of on-site operation in twenty-two social housing apartments. The initial project was a large-scale monitoring on thirty new occupied apartments in two buildings in France equipped with this DCV system, which extended from 2007 to 2009. Thirteen years later the buildings are re-visited, and the monitoring system is turned back on with the intention to assess the ventilation system performance after a prolonged in-situ functioning period. Then, the components have been collected and tested in laboratory facilities: as collected, after cleaning, and finally after a light rehabilitation. Despite largely insufficient levels of maintenance, 100 % of the exhaust units and air inlets not purposely degraded by the occupant, still reacted as expected to humidity. A good relationship was found between the visual maintenance level and the limitation of maximum airflow for each Air Terminal Device (ATD): an average limitation of −10.6 m3/h has been evaluated for ATDs presenting a “Bad” level of maintenance whereas the average limitation was only −2.2 m3/h for ATDs showing a “Good” maintenance state. Finally, after cleaning and refurbishing, but without touching the hygroscopic sensor/actuator, the ATDs still meet the specifications and are very close to their original characteristics.

Hydration and microstructure evolution of a novel low-carbon concrete containing recycled clay brick powder and ground granulated blast furnace slag

This study focuses on a novel low-carbon concrete containing recycled clay brick powder (RCBP) and ground granulated blast furnace slag (GGBFS). The effects of RCBP and GGBFS on hydration process and microstructure of the novel low-carbon concrete with different replacement levels ranging from 0 to 40% have been studied by testing workability, compressive strength, hydration heat, hydration products and pore structure. The incorporation of blended GGBFS and RCBP makes up for the excessive strength loss of concretes with high volume RCBP. Furthermore, RCBP and GGBFS can reduce the cumulative hydration heat and accelerate Portland cement hydration. Samples with RCBP and GGBFS have a lower portlandite content and a high hydration degree at 90 d. Meanwhile, RCBP-GGBFS has an excellent combined effect on optimizing the microstructure. Ultimately, the CO2 emission and cost of mixtures with RCBP and GGBFS are significantly reduced. This study is expected to help enhance the utilization efficiency of RCBP to produce the low-carbon building materials.

The influence of ventilation on indoor air quality in buildings with variable pollutant emissions

Indoor Air Quality (IAQ) assurance is done mainly through the air exchange between interior and exterior. Lack of adequate ventilation of indoor spaces causes poor air quality and a higher incidence of sick building syndrome (SBS), which is manifested by affecting the comfort and wellbeing in the indoor spaces. Ensuring high energy performance buildings and indoor air quality is efficiently approached by limiting emissions from sources, by partial neutralization of the pollutants or by smarter ventilation. The concept of smart ventilation was developed to ventilate properly while reducing energy loads, allow for the provision of grid services, and promote associated renewable power integration. The above-mentioned information can be obtained by the air quality modelling, using mathematical approaches to predict the way pollutants behave in a certain environment or time scale. The paper presents the results obtained by mathematical modelling of indoor air quality, by including the transfer of pollutants from external sources and variable indoor emissions. The considered pollutants are ozone (O3), particulate matter (PM2.5), formaldehyde (HCHO) and carbon dioxide (CO2), due to the significant adverse effects on human health and their different preponderantly sources: indoor, outdoor or both indoor and outdoor. The main goal of our researches is the reducing of the amount of energy that ventilation uses while maintaining or improving IAQ.

Multi-Objective Optimization of Ultra-Low Energy Housing in Hot Summer Cold Winter Climate Zone of China Based on a Probabilistic Behavioral Model

Occupant behavior has an important impact on building energy consumption, and the accuracy of an occupant behavior model directly affects the reliability of energy consumption simulation results. Ultra-low energy buildings are crucial to achieving building energy conservation and carbon dioxide reduction in China. In order to effectively promote the development of ultra-low energy buildings in Hot Summer and Cold Winter Climate Zones. where most residents adopt a “part-time, part-space” pattern of intermittent energy use behavior, and to solve the problem of poor indoor thermal environments and the high incremental cost of ultra-low energy, the study described in this paper takes Changsha as an example to carry out a multi-objective optimization study on ultra-low energy housing using a probabilistic behavioral model. On the basis of a probability model representing the residents’ actual behavior in Changsha, the optimization objective indicators, key variables and the technology benchmarks for ultra-low energy building were determined, then multi-objective optimization was carried out for a range of energy efficient technologies to obtain the Pareto optimal solutions. The results showed that the set of optimal solutions could reduce energy demand by 50.2 to 60.2% and reduce indoor thermal discomfort time by 3.52–11.09% compared with those of a reference base case, which just meets the requirements of the current design standard for energy efficient domestic buildings. An optimum solution for energy savings and indoor thermal comfort, along with economic costs, was identified, which can assist in decision-making by providing different preferences and provide useful reference for the design of ultra-low energy buildings in Hot Summer and Cold Winter Climate regions.

Stochastic planning for low-carbon building integrated energy system considering electric-heat-V2G coupling

The low-carbon building has been proposed to mitigate the climate change caused by environmental problems and realize carbon neutrality in urban areas. In addition, the integrated energy system (IES) has been developed to reduce renewable energy curtailment in the power distribution system and improve energy efficiency due to the independent operation of traditional energy systems. In this paper, we propose a stochastic planning method for low-carbon building IES, in which the Vehicle to Grid (V2G) is also considered to further increase the flexibility of low-carbon buildings. The proposed planning method optimizes the investment and operation costs, and CO2 emission of the building IES, to achieve the maximum benefit of the low-carbon building and help realize carbon neutrality. By considering the uncertainty of distributed renewable energy, multi-energy load fluctuation and the random behavior of EV users, a two-stage stochastic programming model is formulated with chance constraints, in which the heuristic moment matching scenario generation (HMMSG) and sample average approximation (SAA) methods are applied to deal with the uncertainties. In the case study, a real IES office building in Shanghai, where photovoltaic (PV), energy storage system (ESS), fuel cell (FC), EV, etc. are included as planning options, is used as the test system to verify the effectiveness of the proposed planning method, and the functions of the ESS and EV in IES are analyzed in detail in different operation scenarios. The case study results show that the proposed planning scheme can reduce the total cost and carbon emission significantly.© 2017 Elsevier Inc. All rights reserved.

Thermodynamic modelling of CaCO3 polymorphs during CO2 sequestration by cement slurry with the addition of MgCl2

As the largest consumed man-made materials, the production of cement releases a huge amount of CO2 into the atmosphere and dramatically accelerates the global warming. However, the main mineral component of cement can solidify CO2 and convert it into stable calcium carbonate, thus producing low-carbon building materials. In this paper, a thermodynamic model was proposed to simulate the formation of different calcium carbonate polymorphs during the aqueous carbonation of Portland cement with the addition of the most common ionic crystal stabilizer MgCl2. Based on the variations of the calculated Gibbs free energy due to the substitution of magnesium ions for calcium ions, the model can be applied to quantify the proportion of different calcium carbonate polymorphs under different CO2 input amount, MgCl2 concentrations, and temperatures. By comparing the experimental results with the modelling results, the developed model was proved to be able to predict the proportion of calcium carbonate polymorphs with an average relative error of 5.51%. Through experimental and simulation studies, it has been found that 80–90 °C is the most favorable temperature range for the formation of aragonite in carbonation systems. When the concentration of MgCl2 exceeds 0.18 mol/L, calcium carbonate can exist as pure aragonite at near room temperature (25 °C). Considering both the maximum CO2 sequestration rate and the proportion of aragonite, the appropriate CO2 input range is M(CO2)/M(PC) = 0.45–0.5.

A macro-scale optimisation of zero-energy design schemes for residential buildings based on building archetypes

Energy conservation and carbon emission reduction in the building sector have become a global concern in combating environmental issues. To achieve this target, developing low-energy buildings becomes an integral approach. Different from the case-by-case design for public buildings, the geometrical construction form of residential buildings are roughly the same and can be concluded in several representative categories, which leads to several similar paths to achieve energy-saving targets for buildings belonging to the same category. Aiming to determine the applicable design schemes for each archetypal building, the architectural typology method and simulation-based method were used in this research. Furthermore, an optimisation step was done the design schemes from both energy and economic perspectives. As demonstrated in Ningbo city as a case, this research usesthe number of floors, building shape coefficients, average floor areas, and window-to-wall ratiosas classification factors based on previous research and proposed nine representative building archetypes. Subsequently, 512 (29) groups of design schemes combined from nine energy-saving measures were simulated for each building archetype. Considering the energy performance indexes as anenergy-perspective constraintand the life-cycle cost of design scheme as aneconomic-perspective constraint, the design scheme was optimised. The limitation of this research is the neglect of immediate environment such as proximity to other buildings or natural elements such as trees that provided a subsequent research direction. Specifically, this research obtained optimal design schemes of energy-saving targets for individual residential building archetypes in China’s hot summer and cold winter zone. Broadly, this research proposed a comprehensive method for individual building assessment and optimisation that could be further used for a urban-scale energy planning and prediction.

The Reinforcing Effect of Nano-Modified Epoxy Resin on the Failure Behavior of FRP-Plated RC Structures

The ability to manipulate concrete-based and composite materials at the nanoscale represents an innovative approach to improving their mechanical properties and designing high-performance building structures. In this context, a numerical investigation of the reinforcing effect of nano-modified epoxy resin on the structural response of fiber-reinforced polymer (FRP)-plated reinforced concrete (RC) components has been proposed. In detail, an integrated model, based on a cohesive crack approach, is employed in combination with a bond–slip model to perform a failure analysis of strengthened structures. In particular, the proposed model consists of cohesive elements located on the physical interface between concrete and FRP systems equipped with an appropriate bond–slip law able to describe the reinforcing effect induced by the incorporation of nanomaterials in the bonding epoxy resin. Preliminary analyses, performed on reinforced concrete prisms, highlight an increment of 28% in the bond strength between concrete and the FRP system, offered by the nanomaterials embedded in the adhesive layer with respect to the standard one. Moreover, the numerically predicted structural response of a nano-modified FRP-plated beam shows an increment of around 5.5% in the failure load and a reduction in the slip between concrete and the FRP plate of around 76%, with respect to the reinforced beam without nanomaterial incorporation. Finally, the good agreement with experimental results, taken from the literature, highlights the excellent capability of the proposed model to simulate the mechanical behavior of such types of reinforced structures, emphasizing the beneficial effects of the nano-enhanced epoxy resin on the bond strength between concrete and FRP systems.

Novel radiant heating and cooling panel with a monolithic aluminium structure and U-groove surface – Experimental investigation and numerical model

Thermally activated panels with monolithic structure and complex shape are not known well. Additionally, studies of radiant heating–cooling panels described in the literature mainly focus on either cooling or heating as well as either ceiling or wall option. In this paper, a novel heating and cooling panel with a U-groove surface and aluminium monolithic structure that increases heat exchange between the heating–cooling medium and the panel was studied. The performance of a new panel for the wall and ceiling options was investigated experimentally. For this analysis, an extended study was carried out that included both heating and cooling modes to develop a universal solution. A numerical model to predict the temperature in a room with the cooling and heating panels installed was developed and compared with experimental results. The specific thermal capacity of the panels observed in the experiments ranged from 82 to 158 W/m2, sufficient to maintain thermal comfort in modern buildings that meet low-energy or passive building standards. The specific cooling capacity of the studied panels ranged from 47 to 59 W/m2, similar to high-temperature radiant cooling systems used in modern buildings. The investigated panels are compatible with mechanical ventilation systems equipped with a cooling function. The simulation results were in agreement with the experimental measurements. Thus, the numerical model can be used to design heating and cooling radiant ceilings as well as to assess thermal conditions in a room.

Comparative assessment of optical characterization of prismatic materials (PMs), using genBSDF tool for virtual simulations and a goniophotometer for physical measurements

To improve daylight availability and thermal performance of buildings, complex fenestration systems are used to redirect/distribute solar radiation indoors. We need to characterize the optical properties of these complex fenestration systems through measuring their spectral, bidirectional distribution function to evaluate their performance for energy efficiency, daylight availability, and building sustainability purposes. This paper represents the characterization of two different Prismatic Material (PM) products that apply to diverse purposes in buildings. First, we conduct two methods to measure the Bidirectional Scattering Distribution Function (BSDF) of materials; genBSDF raytracing tool of Radiance and goniophotometer measurement (goniophotometry). In the next step, we compare the genBSDF result with the results of the goniophotometry. The aim of this study is to evaluate the angular-based optical behavior of prismatic materials in distributing light and also to assess the reliability of the genBSDF tool result for further simulation of high-performance building purposes. The results demonstrate that the genBSDF raytracing tool method creates a comparable result to the goniophotometry method. Therefore, genBSDF is a robust tool for assessing the solar-optical properties of PMs.

Carbon footprint of low-energy buildings in the United Kingdom: Effects of mitigating technological pathways and decarbonization strategies

There is a limited comprehensive analysis of the effectiveness of adopted carbon mitigation strategies for buildings over their life cycle, that are concerned with temporal perspectives of emissions. Accordingly, this paper explores a life cycle assessment (LCA) to address the concerns regarding mitigating the carbon footprint of a UK timber-frame low-energy dwelling. In particular, it aims to investigate the potential greenhouse gas (GHG) emission reduction in terms of three different heating and ventilation options, and to analyze the influence of decarbonization of electricity production as well as the technological progress of the waste treatment of timber on the building's environmental performance. Thus, the whole life‑carbon of the building case studies was evaluated for a total of eight investigated prospective scenarios, and they were compared to the LCA results of the baseline scenario, where the existing technology and context remained constant over time. Results show that using a compact heat pump would lead to a significant whole life-cycle emission reduction of the dwelling, by 19 %; while GHG emission savings can be reinforced if the assessed systems are employed simultaneously with grid decarbonization, exhibiting a 25 %–60 % reduction compared to the baseline scenario. Moreover, technological changes in the waste treatments of timber products could substantially reduce the buildings' embodied emissions, representing 3 %–23 %. From these emission-saving measures, the contribution of material efficiency strategies to achieve more embodied carbon savings should be highlighted in future construction practices.

Simulation and Experimental Study on the Use of Ventilation Air for Space Heating of a Room in a Low-Energy Building

In thermally modernised buildings, sharing of ventilation heat loss becomes more significant. In the case of the application of ventilation with heat recovery, especially during transitional periods, there arises a question of whether an air system makes it possible to maintain the required indoor air temperature without the necessity of using a basic hydronic heating system. This paper presents the application of a simple thermal network model of a building zone to simulate indoor air temperature in a single room of a multi-storey building with a mechanical ventilation system with heat recovery. Ventilation air was supposed to be the only heat source and its ability to maintain the required indoor air temperature was checked in simulations and then compared with measurements. The 5R1C thermal network model of a building zone was used for simulations. Comparison with measurements showed the Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) of indoor air calculation to be 2.37 °C and 2.45 °C, respectively. When including heat flux from the bottom storey through the floor, MAE = 1.28 °C and RMSE = 1.38 °C were obtained.

Enhancement of fresh and hardened properties of geopolymeric composite containing toxic lead sludge: A comparative study between the effect of superplasticizer and thermal treatment of sludge

Despite the many environmental and economic advantages resulting from the disposal of sludge containing heavy metals in the fabrication of cementitious materials, using a high quantity of these wastes negatively affects the fresh and hardened properties of developed composites. The previous literature proved that lead sludge (LS) from glass manufacturing elongated the setting time and reduced the workability and compressive strength as it contains a large amount of organic matter that adsorbs a high amount of water and hinders the hydration process. Therefore, the main target of this study is trying to find the best methods to enhance the rheological behavior, setting time and mechanical properties of geopolymeric composites containing 50%slag+50%LS (coded: G) via making a comparative study between the effect of adding two doses from naphthalene-based superplasticizer (0.25 and 0.5 wt% NB-SP, coded G-0.25 and G-0.5, respectively) and replacing the LS with thermally-treated one (LS-500, coded G-500). The results indicated that using LS-500 instead of adding NB-SP greatly impacted the improvement of fresh and hardened properties. It was found that the plastic viscosity values were 0.75, 0.63, 0.49 and 0.36 Pa s, while yield stress values were 47.66, 26.38, 19.97 and 3.99 Pa for G, G-0.25, G-0.5 and G-500, respectively. On the other hand, the composite containing NB-SP with LS delayed the setting time until it exceeded the permissible limits (between 45 and 375 min); therefore, they are not valid for in-situ applications.Meanwhile, the initial/final setting time of the G-500 composite was 233/345 min. At 28-days, G-500 has a compressive strength higher than G, G-0.25 and G-0.5 by 28.6, 66.7 and 104.5%, respectively. These outcomes were matched with the thermal analysis technique (TGA/DTG) as the percentages of binding hydrates (CSHs, CASHs and CAHs) for G, G-0.5 and G-500 were 4.85, 2.54 and 7.61%, respectively. Moreover, the alkali-activation of the G-500 composite created a zeolitic-like phase as well as Pb3SiO5, which was detected via XRD and SEM techniques. According to the immobilization test (TCLP), the Pb-concentrations in the leachate solutions of G-0.5 and G-500 composites were 11.5 and 2 ppm, respectively. Therefore, it is recommended to use thermal-treated sludge instead of superplasticizers to produce high-performance and safe building materials.

Energy system and cost impacts of heat supply to low-energy buildings in Sweden

Energy system and cost impacts of heat supply to low-energy buildings in Sweden

Considering embodied CO2 emissions and carbon compensation cost in life cycle cost optimization of carbon-neutral building energy systems

Renewable energy (RE) technologies are regarded as a solution to the climate impact of buildings, but some of these technologies contain embodied CO2 emissions, which have been ignored in most studies. Previous studies found carbon compensation to be necessary for reaching carbon neutrality as even the least carbon-intensive energy production technologies contain emissions related to manufacturing. The novelty of this study was to combine emission and cost calculations into a single method by including the compensation cost for the carbon footprint in the total life cycle cost (LCC) of carbon-neutral building energy systems. Embodied emissions were included in the carbon footprint of the building energy system in addition to operational emissions. The implemented RE technologies were dimensioned in an optimization loop by minimizing the total LCC of the energy system. The method was tested in a case study. The embodied emissions of the studied RE technology options for the case building accounted for up to 48% of the total carbon footprint, and carbon compensation accounted for 0.3–1.9% of the total LCC. The method was proven to be applicable to the cost-optimal dimensioning of carbon-neutral energy system options and is recommended for use in further studies regarding carbon-neutral building energy systems.

Comparative study of greenhouse gas emission calculations and the environmental impact in the life cycle assessment of buildings in China, Finland, and the United States

The building sector is considered a leading contributor to global greenhouse gas (GHG) emissions. With the implementation of China's 2030 carbon peak and 2060 carbon-neutral strategy, significant quantitative research regarding low-carbon buildings is crucial. However, a considerable discrepancy remains between the low-carbon building development in China and other advanced countries; the calculation method of GHG emissions lacks international integration. Based on the life cycle assessment (LCA) theory, a comparative empirical analysis was conducted among residential and public building sets in China, Finland, and the United States considering the life-cycle GHG emissions, which demonstrated notable differences in the Product stage (A1–A3), Maintenance and material replacement stage (B1–B5), and Energy use stage (B6) between each building set. Different building retrofit scenarios were then established to study the emission reduction methods. The results suggest that clean energy sources, materials with low global warming potential, engineered wood structures, and steel structural beams in long-span buildings are conducive to reducing GHG emissions throughout the life-cycle of buildings.