Renovation Of Buildings Research Articles

Energetic and financial evaluation of a district heating network under varying supply temperatures and booster technologies

Low-temperature district heating (LTDH) enables the use of various renewable energy sources, reduces heat losses and increases the energy efficiency of the distribution network. LTDH is especially applicable in energy-efficient buildings as the supply temperature for space heating can be reduced. However, urban areas consist of energetically refurbished and non-refurbished buildings. In these scenarios a LTDH network with a central heat pump (HP) and decentral booster units, such as a booster HP or electrical heater, can be a solution. This study investigates and compares the energetic performance and levelized cost of heat (LCOH) of eight concepts for refurbished and non-refurbished buildings for a district heating network in the city of Ghent, Belgium. The simulations consider supply temperatures ranging from 10 °C to 75 °C. Results show that the primary energy use is lowest when using booster HPs, for both refurbished buildings (402 MWh/year) and non-refurbished buildings (139.6 MWh/year). The LCOH, however, is lowest when booster units are not necessary as the LCOH is mainly driven by the high investment cost of the network and the booster units. This results in a LCOH of 213 €/MWhth for non-refurbished buildings at a network temperature of 75 °C and 297 €/MWhth for refurbished buildings at 55 °C.

Spatial virtual recovery design technology of ancient buildings based on 3D laser scanning technology

Due to the persistent advancements in science and technology, the implementation of digital technology in the preservation of cultural heritage is progressively expanding. One of the focal points of research lies in the spatial virtual restoration design technology of ancient edifices, which is based on three-dimensional laser scanning technology. The study initially outlines the process of obtaining point cloud data via 3D laser scanning technology and subsequently executes denoising, splicing, and simplification processing on the point cloud. Subsequently, the pre-processed data undergo 3D mesh model construction. Finally, an effective repair technique is implemented to address the void phenomenon present during the modeling process. To construct the implicit surface, the RBF method is employed and new vertices are adjusted, resulting in a more accurate spatial virtual restoration of ancient buildings (ABs). The study found that using the radial basis function based void repair method resulted in a mean void repair accuracy of 92.38% in the west wall, an improvement of 3.08% compared to the Liepa-based method. In addition, this method achieved the highest accuracy of 98.94% on the north wall, improving by 6.37% compared to the Poisson grid editing algorithm. Meanwhile, the RBF-based method repaired cavities in the west wall model with an average runtime of only 20.613 s, resulting in a 19.16 s reduction compared to the Liepa-based method. In addition, the method’s average repair time for the north wall was only 5.364 s, a decrease of 13.28 s compared to the Poisson grid editing algorithm. This shows that combining 3D laser scanning technology and cavity repair technology can acquire high-quality point cloud data of historic structures, create precise 3D models, and achieve spatial virtual restoration. This offers a new and efficient technological approach to preserving and passing down ABs.

Improving non-destructive testing methods for detecting cavity damage and internal defects in stone cultural relics: A focus on ultrasonic testing and acoustic tapping technology

This study employs advanced ultrasonic tomography and Grasshopper software to investigate the internal anomalies within stone materials. We aim to enhance the non-destructive testing (NDT) methods with potential applications extending to modern architecture and stone engineering. Cavity damage and internal defects threaten the structural stability of stone cultural relics. Traditional non-destructive testing methods, while practical, have limitations in assessing these relics comprehensively. This paper proposes an enhanced ultrasonic testing method based on mathematical analysis to accurately detect cavity damage in stone cultural relics. We also investigate imaging techniques for internal defects, combining ultrasonic testing with Grasshopper software for efficient and accurate defect characterization. Additionally, we introduce an acoustic tapping method for detecting internal defects in ancient building stones. Verified through field tests and data analysis, this method is non-invasive, accurate, and fast. The process of detecting stone defects using this technology, along with data analysis methods, experimental results, and application effects, are detailed. This research contributes to the improved preservation and restoration of ancient buildings and extends to other fields, such as modern architecture and stone engineering, highlighting its significance in cultural heritage conservation.

The role of policy and regulation in promoting green buildings

Green buildings play a crucial role in sustainable development by reducing energy consumption, minimizing environmental impact, and enhancing occupant health and well-being. This review explores the role of policy and regulation in promoting green buildings, highlighting the importance of government intervention in driving sustainable building practices. Government policies and regulations play a pivotal role in shaping the adoption of green building practices. Through a combination of mandates, incentives, and standards, governments can encourage the construction and renovation of buildings that prioritize energy efficiency, water conservation, and environmental sustainability. Mandatory building codes and standards are among the most effective tools governments use to promote green buildings. These codes set minimum requirements for energy performance, water efficiency, and indoor environmental quality, ensuring that new constructions and major renovations meet established sustainability criteria. In addition to mandatory standards, governments also use financial incentives to encourage green building practices. These incentives may include tax credits, grants, or subsidies for building owners and developers who incorporate sustainable design features or achieve green building certifications. Furthermore, governments can influence the market through procurement policies that prioritize green buildings for public projects. By leading by example, governments can create a ripple effect in the private sector, encouraging more developers and building owners to embrace sustainable building practices. Overall, the role of policy and regulation in promoting green buildings is essential for advancing sustainable development goals. By setting clear standards, providing incentives, and leading by example, governments can create an environment where green buildings are the norm rather than the exception, leading to a more sustainable built environment for future generations.

Optimizing the Building Refurbishment Process Using Improved Evolutionary Algorithms

An optimization model that may be applied to analyze building retrofit strategies is presented in this research. The aim of this research paper is to identify the optimal thermal envelope configuration that will assure the minimum energy requirement for heating in the case of a residential building, while also considering price restrictions obtained through a specific market survey. To achieve this, several values for the following parameters are considered: thermal insulation materials’ conductivities and thicknesses, windows’ overall heat transfer coefficients and total solar energy transmittance and doors’ thermal proprieties. Additionally, this paper presents a method used to find the best option from among the available heat pumps that could cover most of the energy requirements for heating and domestic hot water systems, also considering the products’ prices. The proposed method is based on a Non-dominated Sorting Genetic Algorithm II (NSGA-II) model developed in the Pymoo (Multi-Objective Optimization in Python) library. The result shows that the energy requirement for heating can be reduced by up to approximately 75% compared to that obtained in the case of a non-insulated building by using suitable insulation materials and doors and windows with superior thermal proprieties chosen by the NSGA-II.

Experimental Study on Erosion Modeling of Architectural Red Sandstone under the Action of the Natural Environment

When buildings are exposed to erosion from the natural environment, erosion behaviors such as surface damage and structural instability occur, which greatly affect the aesthetic value and service life of the buildings. The study of erosion behaviors and the establishment of a suitable erosion model are constructive references for the protection and restoration of buildings. In order to establish a suitable erosion model for architectural red sandstone, two types of red sandstone specimens were selected in this paper to carry out dry and wet cycle tests. Combining the theoretical analysis and the actual erosion situation, a unidirectional corrosion model is proposed to describe the erosion of buildings by the natural environment. In this model, it is assumed that only the outer surface of the building is in contact with external erosion factors for a long period of time, so this situation can be considered a unidirectional erosion process. The paper uses XRD, SEM, and ultrasonic methods to record changes in the properties of the red sandstone samples. Finally, the rationality of the unidirectional erosion model was verified numerically. The test results show that the red sandstone specimens subjected to erosion by the natural environment will be accompanied by the development of defects, such as cracks, fissures, and holes, as well as the generation of fresh material. The demarcation point of different erosion stages exists in both the in-service red sandstone specimens and the fresh red sandstone specimens, which is consistent with the results of the unidirectional erosion model. In this paper, a calculation model for the demarcation point of different erosion stages is established, and the model estimation shows that the demarcation point of different erosion stages of the in-service red sandstone sample is 1.1528 cm from the erosion surface, and the demarcation point of different erosion stages of the fresh red sandstone sample is 1.67 cm.

Field Testing of an Acoustic Method for Locating Air Leakages in Building Envelopes

Maintaining the airtightness of building envelopes is critical to the energy efficiency of buildings, yet leak detection remains a significant challenge, particularly during building refurbishment. This study addresses the effectiveness of the acoustic beamforming measurement method in identifying leaks in building envelopes. For this reason, an in-field study employing the acoustic beamforming measurement method was conducted. The study involved testing over 30 rooms across three different multi-story office buildings of varying ages and heterogeneous envelope structures. Numerous leaks were located in the façades, which were subsequently visually confirmed or even verified with smoke sticks. The data, captured using an acoustic camera (a microphone ring array), revealed distinct spectra that indicate the method’s potential for further research. The basic functionality and the significant potential of this methodology for localizing leakages in large buildings were proven.

Research on the Indoor Thermal Environment of Several Traditional Chinese Residential Buildings

To study the indoor thermal environment characteristics and influencing factors of traditional Chinese residential buildings, the existing research studies on the indoor thermal environment of traditional residential buildings were collected and organized, and the relevant measured data was extracted using GetDate software. After data analysis, the construction characteristics of brick and wood structures, wood structures, and raw soil structures were summarized. The indoor and outdoor temperature changes of the residential buildings in summer and winter were revealed. Finally, the indoor thermal environment characteristics and influencing factors of three types of traditional residential buildings were summarized. The research results can provide a reference for the construction and low-carbon renovation of traditional residential buildings.

A Brief Discussion on Technical Points in the Restoration of an Ancient Building in Lanzhou City

With the change and development of The Times, the existing buildings are gradually aging and damaged, coupled with external objective factors and human factors, many building structures are seriously damaged or difficult to maintain the original architectural style. This paper will adopt Revit modeling and combine the principles of ancient building restoration and protection, take the restoration project of Tianqi Temple in Chengguan District of Lanzhou City as an example, analyze the damage of ancient buildings, discuss the reasons for the damage, focus on the analysis of ancient building restoration technology, simulate the construction process of ancient buildings, and provide reference for the future restoration and protection measures of ancient buildings.

Parametric simulation tool for the enviro-economic evaluation of energy renovation strategies in residential buildings with life cycle thinking: PARARENOVATE-LCT

The EU regulations require long-term renovation strategies (LTRS) for the energy transition of the existing building stock, emphasising the importance of the whole-life carbon evaluation and the cost-effectiveness of the processes. The building performance simulation (BPS) tools combined with the integration of the life cycle thinking (LCT) are considered a promising approach for evaluating the renovation of buildings. Besides, the performance gap due to occupant behaviour (OB) and the uncertainty of the economic scenario is an essential barrier to the accurate assessment of renovation strategies in residential buildings. The objective of this study is to develop a simulation tool to evaluate the environmental and economic sustainability of energy renovations in residential buildings based on LCT, considering the OB diversity and economic uncertainty. For this, the study develops the PARARENOVATE-LCT tool. This script-based tool combines the dynamic BPS and the integration of the environmental life cycle assessment (LCA) and the economic life cycle cost (LCC), evaluating different renovation strategies in multiple scenarios based on the combination of multiple variables of archetype, climatic zone, OB patterns, economic scenario and orientation. The methodological tool is applied in a case study of the most common archetypes of single-family and multi-family residential buildings of the Basque Country, in northern Spain. The results show how the tool can prioritise strategies, analyse the significance of baseline scenario parameters, and measure the influence of the LCT application. This way, the study provides a methodological tool as a new approach towards developing policies and plans to answer the EU requirements.

A Final Cost Estimating Model for Building Renovation Projects

The construction sector in Greece has been developing radically in the field of building renovations. The foremost problem for projects in the building construction industry is producing an accurate and reliable cost estimate at the onset of construction. The artificial neural network (AΝΝ) approach, using data available at the early stages of the project, can help resolve or prevent any kind of difficulty that could make the successful completion of a building less likely. ANNs have been highly efficient in gaining results which could prevent the failure of building constructions projects. The ultimate goal is to highlight the usefulness of the adoption of ANNs models to predict the final cost of a building renovation project. Thus, construction companies could avoid financial failure, provided that the gap between cost prediction and final cost for renovation projects is minimized. This paper presents an artificial neural network (ANN) approach for predicting renovation costs in Greek construction projects. The study, based on a comprehensive literature review and real renovation data from construction companies, employs IBM SPSS Statistics software to build, train, and test the ANN model. The model, which uses initial cost, estimated time, and initial demolition cost as inputs, is based on the radial basis function procedure. The model presents high performance with up to 2% sum of squares error and near zero relative error, demonstrating the ANN’s effectiveness in estimating total renovation costs.

A Feasibility Analysis of Energy Retrofit Initiatives Aimed at the Existing Property Assets Decarbonisation

In light of the growing demand for sustainability in the construction sector and real estate market, the European Community (EC) has recently begun incentivizing renovations of private and public European buildings. This aligns with the EC’s aim to reduce harmful emissions by 55% by 2030 compared to 1990 levels, and to achieve complete decarbonization of buildings, i.e., zero harmful emissions in this sector, by 2050. Given this framework, this study aims to verify the financial viability associated with the construction of “green” buildings, as well as the associated monetary benefits related to the efficient nature of these buildings and the resulting reduction in energy consumption. Lastly, an investigation is conducted to determine the economic feasibility of energy retrofit initiatives on existing building assets by comparing the required costs to retrofit against the potential increase in market value of a retrofitted residential unit. Along with assessing the undisputed environmental advantages for the community and all building users, this research aims to assess the financial and economic feasibility of sustainable construction initiatives, providing insight into how best to pursue the EC’s aims.

Characterisation of Adobe and Mud-Straw for the Restoration and Rehabilitation of Persian Historical Adobe Buildings.

In the restoration or rehabilitation of traditional buildings, compatible materials with known characteristics must be used. However, the existing literature lacks comprehensive studies on the characterisation of Persian mud-straw plaster, focusing primarily on Persian adobe. Moreover, previous research on Persian adobe has primarily employed XRF and XRD tests, neglecting ion chromatography, moisture sorption isotherm determination, and thermogravimetric analysis with differential scanning calorimetry. Consequently, there is a shortage of information regarding the elemental composition, mineralogical characteristics, moisture sorption behaviour, and thermal properties of Persian mud-straw plaster, as well as Persian adobe bricks. This paper aims to address this research gap by examining historical and new adobe bricks and mud-straw plaster used in Iran, utilising a comprehensive array of analytical techniques. The results from XRF analysis reveal relatively similar chemical compositions across all samples, while XRD analysis indicates predominantly similar mineral phases. Ion chromatography results demonstrate higher conductivity and chloride concentrations in the mud-straw samples than the adobe samples, with higher values for new samples than historical ones. Freshly used straw, clay, or soil may have higher chloride concentrations caused by the arid climate and soil salinisation in the area. Additionally, moisture sorption isotherm determination results show that adobe and mud-straw plaster with a higher salt load of chlorides have significantly higher moisture absorption. The increased straw quantity in the samples increases the moisture content. Furthermore, thermogravimetric analysis and differential scanning calorimetry indicate that, at low heating, adobe and mud-straw plaster lose water due to dehydration, and at high heating, they lose carbon dioxide due to decarboxylation. The comprehensive characterisation of Persian adobe and mud-straw plaster in this study fills a significant gap in the literature and offers invaluable insights for informing restoration and rehabilitation processes, ensuring the compatibility of the materials used.

Hot Summers in Nordic Apartments: Exploring the Correlation between Outdoor Weather Conditions and Indoor Temperature

As the incidence of extended hot summers in the Nordic climate increases due to climate change, non-mechanically cooled apartments face high risks of overheating. Hence, this study aimed to investigate the temporal effects of heatwaves on indoor temperatures and examine the correlation between outdoor weather conditions and indoor temperature levels. A comprehensive field study was conducted across over 6000 apartments in the Helsinki region during the hot summer of 2021 and its heatwaves. Results indicated that nearly half of the apartments experienced indoor temperatures above 27 °C for over 7 consecutive days. It was found that an outdoor daily average temperature of 19 °C could cause indoor daily average temperatures higher than 27 °C. Further, the study revealed a strong correlation between indoor temperatures and outdoor 5-day moving average temperature, allowing occupants time to take preventative measures. Additionally, a linear relationship was found between the indoor average temperature, the outdoor 5-day moving average temperature, and the 7-day moving average solar radiation. The strength of the correlation and the magnitude of the effects of outdoor temperature and solar radiation varied depending on the duration of heatwaves. This highlights the importance of considering heatwaves in the design and renovation of residential buildings in the Nordic climate.

Economic optimization of exterior wall insulation in Chinese office buildings by coupling artificial neural network and genetic algorithm

Envelope insulation is an essential measure to reduce building energy consumption and is the focus of many building energy codes. In China, the current standard (GB 55015-2021) only specified limit values for the thermal conductivity (U) of the exterior walls, and it ignored variations in building characteristics and internal parameters. Therefore, it is difficult for architects to quickly determine the exterior wall U-value in building design and retrofit. To address this issue, the exterior wall U-values of office buildings in China were economically optimized by TRNSYS, ANN, and GA. To begin with, the effect of enhancing exterior wall insulation on the heating and cooling energy consumption of office buildings was investigated by TRNSYS software, taking into account variations in building characteristics. Moreover, the exterior wall U-values of office buildings were optimized by coupling ANN and GA. The results showed that the design values of the GB 55015-2021 did not achieve the optimal results in China, and the most economical exterior wall U-value was 0.24 W/(m2·K) in Harbin, 0.24 W/(m2·K) in Beijing, 0.42 W/(m2·K) in Changsha, 1.82 W/(m2·K) in Guangzhou, 0.66 W/(m2·K) in Kunming. Compared with the pre-optimization, the annual life cycle cost of building heating and cooling reduced by 0.96 % in Harbin, 2.07 % in Beijing, 1.44 % in Changsha, 1.68 % in Guangzhou, and 7.37 % in Kunming. In addition, variations in building parameters should be considered in the design phase of new buildings or in the renovation of old buildings, such as internal heat gain, which may lead to different optimal results.

Optimising construction waste management in Sri Lanka through Circular economy strategies: a focus on construction and renovation and use and operate stages

PurposeConstruction and Demolition (C&D) Waste Management (WM) poses significant challenges in Sri Lanka, contributing to environmental degradation and resource depletion. To address these issues, this study explores the application of Circular Economy (CE) strategies in minimising waste generation and optimising resource utilisation in Sri Lankan construction industry. The research focuses on the construction and building renovation and use and operate stages of the building project life cycle, recognising their significance in waste generation and resource consumption.Design/methodology/approachThe research employed a qualitative approach, utilising the Delphi technique through three rounds of expert interviews. Seventeen experts were involved in the first round, followed by fifteen in the second round, and twelve in the final round. The collected data was analysed using manual content analysis methods.FindingsThe research findings revealed fifteen C&D WM issues in the construction and building renovation stage in Sri Lanka, along with suitable strategies to overcome each of them. Similarly, eight C&D WM issues were identified for the use and operate stage of the building, and corresponding strategies were provided to address each issue. By adopting CE strategies such as modular design and material reuse, construction projects can optimise the project's timeline, cost, and quality factors. These strategies enable efficient resource allocation, reduce waste generation, and contribute to the overall sustainability of the project. The impact of CE strategies on mitigating these issues within the project management iron triangle was also discussed.Originality/valueThis paper entails delving into how construction, building renovation, and operation stages of a building's life cycle intersect with CE strategies, which profoundly influence operational efficiency and long-term sustainability. By incorporating principles such as energy efficiency, water conservation, and circular product design, the paper illuminates how these strategies facilitate decreased energy usage, enhanced resource management, and diminished waste production throughout the building's lifespan.

RESIDENTIAL BUILDINGS BUILT BEHIND THE STATE INDUSTRY BUILDING (DERZHPROM) IN THE LATE 1920S AND EARLY 1930S: BLOCKS EAST OF NAUKY AVENUE

The article is devoted to residential buildings built in the late 1920s and early 1930s in the metropolitan Kharkiv, in the area behind the State Industry Building (Derzhprom) east of Nauky Avenue. The design andconstruction of these residential neighbourhoods, which took place between 1926 and the late 1930s and had their peculiarities and diversity, are not sufficiently covered in scientific works and require a dedicated study. The preservation, documentation, and restoration of modernist buildings and complexes in eastern Ukraine, especially in the Kharkiv region, require the creation of a periodisation and systematisation of buildings belonging to this glorious period of architectural development. Residential districts created in the 1920s and 1930s in Soviet Ukraine, particularly in the metropolitan Kharkiv, are objects of cultural and historical value subject to documentation and analysis. The tendency to highlight the most outstanding examples leaves out the contextual buildings, which formed the basis of the development of the residential area behind Derzhprom and created a coherent architectural and temporal background of the urban landscape of the new administrative centre of the metropolitan Kharkiv. Meanwhile, the contextual buildings created an architectural setting for more famous examples, such as the Slovo House. When studying the scientific works of Kharkiv architecture researchers, one can pay attention to the coverage of residential blocks to the west of Nauky Avenue, an area with a radial-ring structure, and the almost complete absence of research on residential blocks in the part of the district to the east of the avenue. This fact is quite unfortunate, as the architectural landscape of the blocks in this part of the residential area is notable in its spatial, functional, and stylistic structure. In addition, these blocks are rich in ‘red’ residential buildings, raised in the second half of the 1920s in various cities of Soviet Ukraine, which became a kind of visiting card of life in the Soviet Union then. Keywords: Kharkiv, Derzhprom, residential buildings, Chervonyi Donets, Slovo, KofOk, Chervonyi brodylnyk.

Circular Economy Strategies in Densification and Refurbishment of Residential Buildings – State of Application and Future Directions

The fast population and economic growth put tremendous pressure on the planet’s resources. In this context, the building sector is recognized as one of the most significant contributors to greenhouse gas emissions and the use of raw materials. The Circular Economy (CE) is expected to contribute to a reduction of waste landfills, extraction of raw materials, and greenhouse gas emissions. This study aims to understand to what degree and how CE strategies can be applied to the refurbishment and densification of residential buildings. Using a qualitative approach, this study examines the application of CE strategies in the building sector through five semi-structured expert interviews. The literature identifies five CE principles for buildings: building in layers, designing-out waste, designing for adaptability and flexibility, designing for disassembly, and selecting materials. From the interviews, designing-out waste was the most common approach for refurbishment and densification of residential buildings. Nevertheless, the implementation of CE strategies within the building sector is still limited and challenging due to various barriers and little encouragement. More stimuli from governments through regulations and guidelines, increased collaboration between stakeholders, and technological advancements are expected to reduce the obstacles to implementing CE strategies in refurbishment and densification.

Visual Renovation of Cultural Heritage Buildings through Advanced Construction Materials - 2D-Printed Protective Cladding on Facade Scaffolds

Industry 4.0 has created models of thinking in education, which focus on developing skills through digital creative learning. This is increasingly being applied to the solution of multidisciplinary problems of great importance to societies. The preservation of Bulgaria's cultural heritage is a task that requires such approach. This paper proposes to combine technical experience with technological advancements and, as a result, to cater for elements of the life cycle of heritage buildings and cultural monuments that are at risk.

Dating of oak timbers from Anadolu Hisarı (Anatolian Fortress), İstanbul-Türkiye

Anadolu Hisarı, or the Anatolian Fortress, is a prominent historic building located on the Anatolian side of Bosphorus, Istanbul, right across the well-known Rumeli Hisarı (the Rumeli Fortress). The fortress is known to have been built during the reign of the Ottoman Sultan, Yıldırım Bayezid, in 1395. In 2022 during the restoration of the fortress we collected a group of stem discs from six timbers stored in its garden for dendrochronological dating. The timbers were dated to 1395 after standard dendrochronological methods were applied. This result is consistent with the completion dates of the construction, 1395-1396, mentioned in historical records. The part of the walls from which the sampled timbers had been removed are from the original construction and were replaced during the recent restoration work. Our study shows that identifying the exact context of architectural wood removed during restoration of such historical buildings in Istanbul can help identify their original parts and the time of restoration activities that may have taken place in the past.