Rehabilitation of Heritage Buildings in Conflict Zones: A Case Study of Al-Khader Library in Gaza Strip and Its Impact on Sustainable Development

Abstract

Rehabilitating heritage buildings is a common practice in developed countries. In contrast, developing countries experiencing conflict lack the financial support and qualified experts to restore heritage buildings. This article focuses on the restoration of the al-Khader building in the Gaza Strip, part of a UNESCO project aimed at preserving historical buildings. This study aims to explore the challenges and impacts of the adaptive reuse of the al-Khader building as a children’s library for the local community and to explore the impact of this project on sustainable development and its importance locally, as well as the role of this building restoration and rehabilitation through Quintuple Helix dimensions. Qualitative methodology was used, including field observation and interviews, to present the project stages during restoration in 2016. The interviews were conducted with library users, employees, and visitors to evaluate their experience in 2019. The research revealed that the restoration process faced several challenges, including a lack of experience and professional workers in conservation work. Despite challenges, the building’s transformation positively affected heritage preservation and the local community, aligning with 11 Sustainable Development Goals—directly with 7 goals (SDGs 4, 7, 8, 11, 12, 16, and 17) and indirectly with 4 goals (SDGs 1, 5, 9, and 13). The findings emphasise the role of the library’s rehabilitation in contributing to the success of the Quintuple Helix in economic and civil society systems and the need to enhance the consideration of government, education, and environmental systems. Finally, this project, which external donors funded, increased awareness among local people of the importance of heritage buildings. Unfortunately, due to the ongoing conflict in Gaza, the current status of the building is unknown. This study, therefore, serves as necessary documentation of the building as it was in 2023 and prior.

1. Introduction

Heritage buildings are essential in reflecting history, society, culture, and tradition, increasing people’s awareness about themselves and their identity [1]. The rehabilitation of these buildings goes beyond simple preservation; it involves adapting them for contemporary use while respecting their historical significance [2]. Rehabilitation and adaptation efforts often include structural repairs, the use of traditional materials and techniques, and the incorporation of modern amenities to make these buildings functional in today’s context [3]. Heritage building rehabilitation plays a crucial role in cultural sustainability by maintaining the physical manifestations of a community’s history and values. These buildings serve as tangible links to the past, fostering a sense of belonging and continuity [4]. Therefore, many conservation guidelines have been established in the four decades since the Venice Charter was adopted in 1964. These guidelines, which take the form of charters, principles, and recommendations, have meticulously defined the scope of heritage and its broader definitions [5,6,7].

1.1. International Considerations

International entities such as UNESCO and ICOMOS are dedicated to preserving cultural property. This preservation includes historic structures, monuments, architectural buildings, sites, and cities worldwide, which they strive to safeguard from various risks [8,9,10,11,12]. The United Kingdom Institute of Conservation UKIC (1983) defines conservation “as preserving an object’s true nature, the true nature of an object includes a demonstration of its origins, its original construction, the materials of which it is composed, and information on the technology used in manufacture” [13]. Conservation is a process undertaken to extend the life of historic structures. This process involves a range of measures such as restoration, preservation, reconstruction, rehabilitation, and adaptation [14].

As mentioned previously, UNESCO plays a significant role in conserving heritage buildings. UNESCO encourages the identification, recognition, protection, and preservation of natural and cultural heritage worldwide, considered of remarkable value to humanity [15,16]. The principle of conservation is embodied in an international agreement known as the Convention Concerning the Protection of the World Cultural and Natural Heritage, which was instituted by UNESCO in 1972 [17]. UNESCO’s guidance on the Historic Urban Landscape also underscores the importance of implementing a ‘transformation through conservation’ strategy. This approach emphasises the management of changes within the historic urban area [18]. Thus, conservation and rehabilitation practices have been employed to sustain or enhance the functionality of heritage buildings. Beyond their impact on the buildings’ characteristics, these interventions contribute to the residents’ quality of life, coinciding with the development of the surrounding area [19].

1.2. UNESCO’s Role in Palestine

In the Middle East, UNESCO plays a significant role in conserving heritage buildings. The region of the Arab States, comprising 19 member countries that have ratified the Convention Concerning the Protection of the World Cultural and Natural Heritage, is home to 88 sites that are currently recognised on the World Heritage List. This region is recognised for its valuable cultural and natural heritage, showcasing diverse values and characteristics. It contains various historical periods, from prehistoric to contemporary [20].

In the case of Palestine, the conservation of historical buildings takes on an essential role due to the presence of the occupation to protect Palestinian national identity [1]. In 2012, UNESCO and Sweden launched a project to restore and protect the built cultural heritage in Palestine. The project, which lasted nearly a decade and cost USD 18 million, aimed to revive sites that no longer serve their communities or contribute to local development. Throughout the project, UNESCO and its partners rehabilitated and restored 75 sites in the West Bank, Gaza, and Jerusalem. These sites are now successful structures that serve their local communities in many ways [21]. The project has positively promoted local development by rehabilitating and restoring the historic built environment in Palestine [22].

On the other hand, the ongoing conflicts in Palestinian areas have increased the value of heritage buildings and emphasised the importance of conserving them and ensuring their sustainability. In the case of the Gaza Strip, as an area experiencing a full blockade and repeated aggression, this importance is essential to protect and conserve its culture and heritage buildings. This conserved project, al-Khader, is considered the second project funded by UNESCO for restoration in the Gaza Strip. The first project was the al-Sakka residential house, which was transformed into a women’s centre for ten years before returning to its owners according to the conditions of the financing entity [21].

1.3. Contribution to Sustainable Development Goals

Consequently, in September 2015, the United Nations established the 17 Sustainable Development Goals (SDGs) with a global transformation goal set for 2030 [23]. Before this, in 2013, UNESCO underscored the significance of culture in sustainable development policies [12], integrating the Sustainable Development Agenda with cultural heritage. In November 2015, the 20th General Assembly of the States Parties to the World Heritage Convention adopted a policy to incorporate sustainable development into its processes [24]. Subsequently, UNESCO launched the Culture for Sustainable Urban Development programme [25], emphasising the role of culture in sustainable development and explaining the connection between implementing the UNESCO Culture Conventions and achieving the SDGs. This association makes cultural heritage a vital component of sustainable development, as reflected in the SDGs, either directly or indirectly [26,27].

There is a general consensus, in Lerario’s 2022 study, that culture and heritage are connected to various SDGs, though the full extent of these links is not completely traced. For example, De Vries identifies connections with SDGs 4, 8, 11, 13, 16, and 17, while the British Council sees links with all 17 SDGs. Petti et al. specifically note cultural aspects in SDGs 4, 8, 12, and 16 [2]. Specifically, rehabilitation projects for heritage buildings offer a unique opportunity to contribute to the SDGs [26]. For instance, by ensuring the structural integrity and usability of heritage buildings, such projects support SDG 11, which aims to make cities inclusive, safe, resilient, and sustainable—precisely target 11.4—and Goal 8, target 8.9. Moreover, the use of traditional materials and methods in rehabilitation supports SDG 12 by promoting sustainable practices and reducing waste [15,27]. Despite this, they have not been directly addressed in the other Goals; these projects often require collaboration between governments, private sector entities, and local communities, thereby fostering partnerships as envisaged in SDG 17 [2]. Finally, numerous obstacles and challenges exist in obtaining sufficient data and creating systematic methodologies for cultural heritage to realise and measure the progress of the SDGs [28].

1.4. Application of the Quintuple Helix Model in Heritage Building Rehabilitation

The call to action for a more sustainable, secure, and prosperous planet is important for humanity. It necessitates the collaborative efforts of individuals, businesses, and governments, which are vital for achieving the SDGs [29]. This shared commitment among various actors and stakeholders is key to creating lasting value for society and business. The Quintuple Helix Model’s analytical framework illustrates the interplay among societal actors attempting to progress. It comprises education, government, civil society, and economic and environmental systems. These components of the Quintuple Helix Model and their knowledge subsystems are interconnected at national, regional, and global levels [30]. Moreover, scientific studies assert the role of the Quintuple Helix Model in integrating these systems for the SDGs’ sustainable development to extend its applicability to addressing societal challenges [31]. This model emphasises the importance of sustainable development and the integration of societal and environmental concerns into the innovation process. It recognises that innovation and knowledge production are deeply intertwined with societal and ecological contexts, making it particularly relevant for addressing complex, multi-dimensional challenges [32].

Heritage building rehabilitation is a complex process that benefits from the comprehensive perspective provided by the Quintuple Helix Model. Including civil society and the natural environment in the rehabilitation process ensures that these projects are economically viable and technically sound, socially inclusive, and environmentally sustainable [33]. The model facilitates collaboration among diverse stakeholders, including local communities, governments, academic institutions, private sector entities, and environmental groups, leading to more innovative and sustainable rehabilitation outcomes [32].

In the Gaza Strip, the study area faces significant challenges due to the ongoing conflict. The region’s infrastructure and heritage sites have been severely impacted. The al-Khader Library, a historically significant building, has deteriorated over the years. The restoration and rehabilitation of this library presents a unique opportunity to explore the intersection of heritage preservation and sustainable development in a conflict-affected area. The goal of rehabilitating the al-Khader Library is to integrate traditional construction techniques with modern sustainable practices to preserve its historical integrity while improving its functionality and resilience. This project aligns with several SDGs and is aimed at assessing its broader impact. The study will focus on the methods and materials used, challenges encountered, and outcomes achieved during the restoration and rehabilitation process. Additionally, it will evaluate the project’s impact on sustainable development in Gaza, considering community engagement, cultural preservation, and economic revitalisation. By documenting and analysing this case study, this research aims to provide insights and recommendations for similar initiatives in other conflict zones, contributing to the global dialogue on heritage preservation and sustainable development.

2. Materials and Methods

2.1. Research Aim, Objectives, and Significant

This study focuses on the al-Khader building as a case study for rehabilitating heritage buildings. The study aims to highlight the role of building restoration and rehabilitation as a vector for sustainable development within the local community. This aim is achieved through two objectives:

(1)

Evaluating the restoration process and users’ experiences within the building rehabilitation.

(2)

Assess how the library function aligns with the SDGs.

The significance of this research is emphasised by its exclusive evaluation of the al-Khader building, one of the first restoration and rehabilitation projects within the Gaza Strip. This case study is a practical model for preserving heritage buildings, offering valuable insights into best practices. Furthermore, this research contributes significantly to the existing body of knowledge by filling a gap in the literature on heritage conservation studies in Palestinian cities.

2.2. Research Method and Data Collection

This research employed a case study methodology to collect, interpret, and analyse relevant data to convey the research findings. The case study approach is used within the field of heritage conservation, as evidenced in prior studies [34,35,36,37,38]. This research involves purposeful sampling and selecting information-rich cases for in-depth study [39].

Several qualitative research methods were utilised in this study. These methods involved case study analysis, interviews, field observations, and architectural and photographic documentation. The case study analysis primarily relied on field observations to gather detailed information regarding the building’s physical characteristics, including its exterior structure, interior condition, spatial layout, and finishes before restoration. After the rehabilitation, a comprehensive follow-up evaluation was conducted, which included additional field observations and post-occupancy evaluation to assess the users’ experience with the building’s new function. Interviews were also conducted to understand the transformation’s impact on both users and visitors. It is important to justify the number of observations and interviews conducted. Despite the limited number of visits and interviews, the observations were thorough and provided a comprehensive understanding and evaluation of the place. Regarding the interviews, the responses were consistent and repetitive, indicating that the number of interviews conducted was sufficient to capture all the necessary details and insights. This approach aligns with previous research, demonstrating that in-depth observations and fewer interviews can be effective in qualitative research, especially when the data becomes saturated, meaning no new information is obtained from additional interviews [40].

Table 1. A summary of the qualitative research methods employed in the case study.

Research Methods	Field Research and Stages
	Pre-Restoration	During Restoration	Post-Restoration
	2016		2019
Field Observation	Survey site observation Damage evaluation	Field observation on treatments and supervision	Field observations and occupancy evaluation (4 h) visit after occupancy in February 2019
	The second author’s supervision during the restoration work (From March to December 2016)
Interviews Face-to-face semi-structured interviews	The second author was an active participant in the restoration process. 1 project supervisor (1 h)		With users in February 2019 3 employees (1.5 h) conducted by the IWAN team 16 children + 8 parents (5 h) conducted by the library supervisor from the same field
Photographic documentation (exterior, interior)	Field visit	Field visit	Field visit (4 h) visit after occupancy
2D modelling plans	Existing plan—Architectural drawings	1- Proposed plan. 2- Adjusted developed plan/sections to the final plan—Architectural drawings

provides a detailed summary and description of the qualitative research methods used in the case study.

(1)

Observation

The second author conducted field observations at the al-Khader building before and during its restoration from March to December 2016. The restoration process was divided into two main stages: assessment and treatment. During the assessment stage, an architectural survey of the building was conducted, its problems were identified through field observations and photographs, and damages were assessed for proper treatment. The information gathered was then used to determine any restrictions on adaptive reuse and allowable alterations to the building’s physical characteristics and surrounding environment. The treatment stage focused on adapting the building to meet the contemporary requirements of its new function without affecting its traditional character. The solutions and treatments included studying the spatial layout, using local materials and adding new spaces as needed for new functions. Following the restoration, a post-occupancy evaluation was carried out in February 2019 through a comprehensive 4-h site visit by the IWAN team to assess user perceptions regarding the new functionality of the building.

(2)

Interviews

A total of 28 face-to-face semi-structured interviews were conducted with the project supervisor, employees, child visitors, and their parents to gather their opinions and perceptions towards the building restoration and library. The interviewees were selected based on their ability to contribute to the study. These interviews were carried out in February 2019 and completed within a month. The second author and IWAN Cultural Heritage Centre employee interviewed three library employees. Additionally, one of the library supervisors interviewed 16 children between the ages of 10 and 15 who regularly visited the library, in addition to 8 parents. All these interviews were conducted at the same location, the case study building.

The questions posed to the employees aimed to assess how the adaptive reuse of heritage buildings promotes social and cultural sustainability. Furthermore, they sought to identify challenges or opportunities that may influence cultural sustainability within the surrounding community. On the other hand, the questions directed towards the young visitors aimed to evaluate their perceptions of how well the building serves its new purpose as a library based on their experiences over the past two years. In addition to these interviews, insights were gathered from eight parents regarding their perceptions of the library.

2.3. Data Analysis

Narrative analysis was used as the primary technique for analysing the collected data. The researchers analysed the text from the interviews and the observation notes to develop a deep understanding of the outcomes. This process effectively facilitated the achievement of the study’s objectives. Furthermore, recent cultural heritage studies have incorporated the Quintuple Helix Model in their assessments of heritage buildings [4,41]. Consequently, this research utilises the Quintuple Helix Model as an analytical framework to explain the interaction between the five systems (government, education, economics, civil society, and environment) with the influence of the direct and indirect goals and targets of the SDGs in the al-Khader building, as demonstrated in prior studies [4,30].

3. Case Study Background

3.1. Case Study Area

The al-Khader traditional building in Deir el-Balah lies in the middle of the Gaza Strip in the southern part of Palestine (Figure 1). According to the Palestinian Central Bureau of Statistics, the Gaza Strip has a total area of 365 km² and a population of around 2.1 million distributed between five Governorates. Deir el-Balah is a city in the middle of the Gazan Governorate ‘Alwosta’, which is one of 16 Governorates of the Palestinian territories. It is in the centre of the Gaza Strip, with a total land area of 17.4 km² and a population of 302,507 inhabitants [42]. The city of Deir el-Balah is recognised for its abundant date palms, which have inspired its name.

3.2. Overview of the Al-Khader Historical Building

In Gaza, the formerly dilapidated edifice of the al-Khader Monastery is believed to date back to 1700 BC, making it one of the oldest (if not the oldest) sites in the Gaza Strip [21].

Al-Khidr Mosque, also known as Maqam al-Khader, was constructed on the grounds of a former Byzantine monastery. Its north and south walls are reinforced with buttresses, and the east wall features three apses. The Survey of Western Palestine, conducted in 1875, noted the discovery of Greek inscriptions on one of the steps leading to the southern wall’s door and a broken stone slab marked with two Maltese crosses on the floor, resembling a tombstone. More slabs and Greek inscriptions were found in the mosque’s eastern section and its courtyard. At the mosque’s centre lies a tomb built from modern masonry, traditionally believed to be the tomb of Saint George, or al-Khidr in Arabic [43].

The al-Khader Monastery building is situated at the heart of a residential neighbourhood and can be accessed from a local street in the northern part of the city centre. The building showcases a unique architectural style reflecting Christian and Islamic cultural heritage. It is divided into two sections: the old section, which dates to the Roman period, is located below ground level, while the other section above ground level was constructed as a prayer area during the Islamic era following the Crusades. The building had been abandoned and neglected until it was rehabilitated.

In March 2016, the Ministry of Tourism and Antiquities in the Gaza Strip initiated the restoration of the al-Khader Mosque with financial support from UNESCO and the Nonprofit Association of Washington (NAWA) Foundation. The building was aimed to transform the mosque–tomb into a children’s cultural library [44]. This new function was defined according to the community’s needs and paralleled the main concept of many restored buildings worldwide [45]. The al-Khader traditional building was rehabilitated in cooperation with the IWAN Cultural Heritage Centre at the Islamic University of Gaza and the RIWAQ Centre for Architectural Conservation in the West Bank. The Swedish Government funded this project through UNESCO and the Belgian Wallonia Foundation proximately for USD 88,000 [46].

4. Al-Khader Building Restoration Analysis

In March 2016, the restoration process was carried out and analysed in two main stages: pre-restoration and during restoration:

4.1. Pre-Restoration Conditions

A. 

Preliminary Assessment

• Site analysis and historical research:

The initial observations revealed that the building features load-bearing walls constructed from thick, locally sourced stone, specifically sandstone, which is popular in Gaza City heritage buildings [47]. These walls are integral to the structure, providing essential support for the ceiling. The front area’s ceiling is characterised by three hemispherical domes crafted using traditional masonry techniques and a flat ceiling in the rear. Sand mortar, a traditional material made from a mixture of lime and sand, is used to bind the stonework. This mortar holds the stones together and enhances the building’s longevity and resilience, maintaining a connection to historic construction practices that were used in Gaza City for many historical buildings [47]. The building includes two main areas: the first area is the outdoor area (L-shaped courtyard), which has the main entrance with a simple wooden door on the southern side (Figure 2A). A small area called ‘Azeer’ beside the entrance was traditionally used to store water (Figure 2B). The main door leads to an open courtyard with an area of approximately 85 m² (Figure 3; C1). The second area is the building area, with a total area of approximately 116 m², with two levels. The upper-ground level is in an L-shaped structure and has three spaces (Figure 3; R1, R2, and R3) with hemispherical domes and two stone facades with pointed arches on their western and southern sides; they are built from regular sandstone from the early Islamic era (the Ottoman era) (Figure 2C). Space (R1) has a sizeable semi-circular niche called ‘Mihrab’ for Muslim prayer. The underground level is the oldest part of the space (R4), a rectangular chapel that extends from east to west; it is built from irregular sandstone from the Byzantine era with grain/cross-vaulted ceilings (Figure 3). In space R1, three hemispherical domes were discovered, constructed using clay pottery pots bonded with mud mortar, a technique traditionally employed in dome structures found in Ottoman architecture [48]. Traditionally, and even today, clay pot-making has been widely practised in the Gaza Strip [46]. The pots were placed in the dome radially as the vertical axis of each pot is directed towards the central point of the concave dome form. These pots, with a depth of 30 cm and width of 25 cm and a top opening diameter of approximately 7 cm, not only add a practical aspect to the building but also offer several advantages. These pots effectively contribute to thermal conditioning, reduce the structure’s overall weight, provide sound insulation, and represent an economical choice as they use available natural materials from the local environment [48]. As the project supervisor revealed, two of these domes have pottery in one part and clay stone in another, suggesting they were from different ages. The third dome is composed entirely of pottery from the inside (Figure 2D,E).

• Identification of degradations and damages:

The identification was conducted to ensure the compatibility of the properties of these materials with those of the original building materials, as recommended in [49]. Professionals use tools such as the “Illustrated Glossary on Stone Deterioration Patterns” by ICOMOS-ISCS to identify and categorise the present types of decay. Several types of decay were observed in the sandstone structure and classified according to ICOMOS-ISCS (2008) [50], as shown in Figure 4:

• Cracking: Hair cracks (minor) were identified in several structural elements, likely caused by thermal expansion, freeze–thaw cycles, or mechanical stress, especially in the older parts as in Figure 4B. Some cracks were superficial, while others appeared to penetrate deeper, splitting and fracturing the stone in the L-shaped area as in Figure 4C.
• Scaling: Extensive scaling was observed, particularly on vertical and dome surfaces. This form of decay manifests as the detachment of stone layers, often due to thermal stress or moisture infiltration, leading to the loss of surface material.
• Biological Colonisation: The presence of lichens, moss, and other biological organisms was noted on the shaded and moisture-retentive areas of the sandstone. This type of decay can lead to the biochemical deterioration of the stone surface (Figure 4E,F).
• Efflorescence: White, powdery deposits were observed on the surface, indicating the presence of soluble salts. This decay pattern is particularly problematic as it can lead to further deterioration, which leads to extensive scaling and peeling patterns, major disintegrations, and splintering (Figure 4B).

B. 

Diagnosis:

• Condition assessment:

A detailed assessment of the site was conducted to understand the extent of its deterioration, including structural integrity and material degradation factors:

• Exterior condition assessment:

According to the observation and the interview with the project supervisor, a large part of the northern wall collapsed in the winter of 2011, which affected the building’s structure. Several cracks in the chapel room weakened and dampened the remaining part of the wall. Some stones also collapsed and gradually fell off. In addition, the eastern wall of the building was damaged during the aggression on the Gaza Strip in 2014, which caused some stones to fall off the wall. However, this damage did not constitute a structural danger to the building.

An inspection was carried out to assess the existing damage. The damages identified include the growth of plants between the wall stones and, on the roof, multiple cracks in certain areas of the building; the application of cement plastering and painting; and a collapsed section of the northern wall of the building (Figure 5A–C).

2.

Interior condition assessments:

Inspecting the building’s interior spaces reveals structural damage, including numerous cracks in certain areas. Scaling and old cement plaster and paint on the walls and domes were also noted, as these were applied in previous uses of the building to cover up the original limestone. Increased humidity has a significant impact on the underground structure, resulting in the growth of lichens, moss, and other biological organisms in shaded, moist areas of the sandstone. Additionally, white, powdery deposits have been observed on the surface, indicating the existence of soluble salts (Figure 5D,E). Scaling and deposits were observed over the three hemispherical domes, where clay pottery pots attached to mud mortar were revealed. Some of the pots were broken at the base, and the detached material from the sandstone blocks had accumulated as deposits (Figure 5F,G).

4.2. During Restoration

A. 

Planning:

• Conservation Plan Development:

This phase contained two main steps: The planning process involved implementing conservation interventions and actions. This included forming the design and conservation teams and proposing necessary additions and interventions to suit the building’s new function. The following step focused on executing restoration treatments, which were determined based on the identified damages to the building and its new function.

The restoration treatment process also considered various sub-elements, including building facades, openings, and construction and finishing materials. Furthermore, the evaluation assessed whether the new elements were distinguishable from the old ones and if the new function was compatible with the building’s structural durability; this was clarified in the study by Alhojaly, Alawad, and Ghabra [51].

• Stakeholder Consultation:

The stakeholders’ and design/conservation teams’ approach to the restoration process was guided by the regulatory frameworks established by UNESCO (2011) [11]. These frameworks highlight the significance of respecting local conditions and integrating environmental, social, and cultural values into the regulatory measures for managing heritage buildings. The stakeholders, whose involvement is crucial for the success of the project, ensured the conservation plan aligns with broader societal and cultural goals, meeting their needs and preferences in the surrounding neighbourhood.

B. 

Intervention:

• Execution of Restoration Works:

The implementation of the building’s conservation and restoration began with a detailed process. This involved taking all measurements manually, drawing them using AutoCAD, and preparing the complete layouts for the sections and interior facades. Restoration was then conducted according to the assessment, and damage identification was carried out, providing a clear understanding of the project’s progression.

The restoration process began with site preparation and cleaning, which involved completely removing cement plaster from the walls and ceilings and eradicating its remnants from the natural sandstones. This was followed by reinforcing external walls and injecting cracks with a traditional mortar made from lime and sand. Traditional plaster, also made from lime and sand, was applied to the surfaces, and mortar was inserted between the stones as a sustainable material. Necessary electrical and drainage networks were installed within concealed spaces to keep them hidden.

A significant discovery was made in this building during the excavation and cleaning phase while removing the cement plaster on the western chapel facade of the underground space (R4) (Figure 3): a large gate with a pointed arch, previously closed with irregular sandstones, was uncovered (Figure 6). This important discovery requires additional work and requires the stakeholders to make a final decision.

The stakeholders and the restoration team agreed to start the excavation work. This involved making changes to the original project design with a new layout and working on removing irregular sandstones that were blocking the gate. During this process, they uncovered a rectangular void (spaces of C3 and C2) (Figure 7). This void was enclosed by a wall approximately 1.7 m high, constructed from irregular sandstone on clay soil. Following the decision to preserve this newly discovered section, this unexpected finding necessitated additional modifications and developments to the proposed project design, including architectural and structural drawings and adjustments to the project timeline and budget.

The discovered gate is shaped like a pointed arch leading from the chapel on the western side. The discovered space is enclosed by four ancient walls with varying heights, constructed from irregular sandstone on clay soil. To access the lowest level of space (C3) (Figure 7A) in the underground area, a retaining wall of 25 cm thickness and varying heights between 70 and 100 cm was erected to support the clay area for the southern and western walls. Above these retaining walls, the old irregular sandstones were preserved in space (R5), as illustrated in sections A-A and B-B (Figure 7B,C). These retaining walls were created to strengthen the underground space, potentially reusing it as a gallery. The eastern and southern space walls (R5) were plastered, while the western wall was left un-plastered. In the upper-ground space (C2), the old irregular sandstone on the eastern wall extends to the ceiling of the upper space’s roof. However, there was a need to construct concrete blocks over the irregular sandstones for the other walls, potentially reusing this area as an art room. Six piles were constructed to support the roofs of both the gallery and the art room (Figure 7A,B). An iron staircase was installed in space (C3), providing access from the underground part (R4) to the art room above space (C2). On another note, the eastern wall of the chapel (R4) features a large semi-circular niche (apses) centred between two smaller niches, with an additional niche found in the northern wall.

Additional interior spaces were necessary to construct new areas using concrete to optimise the available space and accommodate the building’s new function. Cement was used exclusively for these new sections, ensuring that the restoration of the old building remained unaffected (Figure 7). This includes the following:

• The discovered lower space was repurposed as a gallery, utilising a concrete structure.
• The upper space located in the western area above the gallery was used as an art room. The eastern stone wall of the art room was repaired, while the remaining walls were constructed from concrete.
• Additional facilities, including toilets and a small kitchenette, were combined using concrete construction, which was only used for the new part.

1. Exterior work treatments:

• Plastering Works: The old cement works and plants were removed, and traditional plastering from lime (hydrated lime) and sand was applied to the domes to fill the cracks between stones. Grouting from lime and sand was utilised on the exterior walls to maintain the stone appearance. The damaged section of the northern wall was reconstructed using traditional methods, incorporating imported sandstone from the West Bank, Palestine (Figure 8A). This approach ensured that the new structure closely matched the existing one, thereby enhancing its sustainability.
• Arch Construction: A semi-circular arch was constructed to recognise the art room in the new area from the pointed arches that were originally present in the old part of the building (Figure 8B). This arch was designed in a different style to showcase the contrast between the current and old styles.
• Ceiling Steel Structure: A steel mesh structure was integrated to enclose the courtyard and the building, preserving both. Portions of the ceiling were installed with vibrant plastic decorations, adding a touch of colour. This architectural addition has transformed the space into a communal area for shared use (Figure 8C). A system of solar panels was installed on the roof to enhance energy efficiency and support environmental sustainability (Figure 8D).

2. Interior works treatments:

• Ceiling Work: In the three hemispherical domes, these potteries were filled with plaster and painted with lime to blend in seamlessly with the walls. The domes underwent structural consolidation in various areas with traditional plastering techniques employed to fill in the scaled and cracked sections, ensuring the integrity and continuity of the surface (Figure 9A,B).
• Plastering Work: The old cement work and scaling sections were removed, and traditional plastering using a mixture of hydrated lime and sand was applied to the interior walls and ceiling, effectively filling the joints and cracks between the stones. The conservation team diversified the appearance of the stones in the interior walls. Stones in good condition were maintained without plastering, and those in poor condition were maintained and plastered, especially on the upper level. The stones on the lower part were cleaned of lichens, moss, and other biological organisms, while the efflorescence was removed mechanically using a sponge with distilled water.
• Tiling Works: The upper spaces of the building and the courtyard were paved, while the tiles in the underground part were preserved.
• Electrical and Sanitation Work: Electrical systems were embedded in the stone walls before plastering and filling the joints to provide suitable lighting for all spaces. Plastering and filling joints also concealed air conditioning and solar energy installations.
• Drainage Work: Drainage work was primarily performed for specific service areas, such as the kitchen and toilets. A rainwater drainage system was installed in the courtyard and on the building’s roof.

3. The New Spatial Planning/Functions:

The building interior is divided into two main levels: The upper-ground level, which consists of three main spaces, has been transformed into reading zones. These zones are furnished with visually appealing bookshelves tailored for children. Architectural features such as wall arches and niches have been creatively utilised as accent bookshelves (Figure 10A). The Mihrab space is embellished with Arabic calligraphy, adding a cultural essence (Figure 10B).

The underground level is accessed by a staircase leading to a lower hall, designated as a narration and storytelling hall (R4) (Figure 10C). To preserve a glimpse of the Byzantine era in space (R4), a section of this hall’s front wall has been encased in glass and left unrestored (Figure 10D). The lower space, revealed during restoration, is a gallery area for archaeological artefacts discovered on site (Figure 10E). A metal staircase connects the underground spaces and those on the western side above ground (Figure 10F). Above this area, a space has been designated as an art room (Figure 10G). Both levels are reinforced with concrete. For the service area’s exterior facade in the front courtyard, decorative stones were selected to harmonise with the adjacent stones. The courtyard function is a communal area for activities (Figure 10H).

5. Post-Restoration: Al-Khader Building Rehabilitation Evaluation

5.1. Post-Restoration Evaluation: The Building

The al-Kader building underwent treatments tailored to its specific damage and requirements. To preserve its unique character and remain in the Venice Charter in accordance with its stipulations, the original materials were conserved. The Venice Charter of 1964, in Article 9, emphasises that “restoration is a highly specialised operation” [8], and any necessary additional work “must be distinct from the architectural composition and bear a contemporary stamp” [49]. This principle was duly followed in the restoration of the traditional al-Khader building. According to the supervisor of the al-Khader project, the donors of these projects demand that the buildings they finance be reused for the community’s benefit. Once the donor consents to provide funding, the design team and beneficiary associations collaborate to determine the best way to reuse these traditional buildings. They attempt to present architectural layouts that, as much as possible, respect the traditional spaces while accommodating new requirements. Accordingly, adapting a building for reuse often necessitates the addition of spaces such as toilets and kitchens and incorporating modern materials. While the concrete structure of the al-Khader building may not be immediately noticeable from the exterior, its distinctive qualities become apparent upon viewing the interiors.

Post-restoration field observations reveal that the building’s outdoor area, or courtyard, is now utilised as a gathering and activity space for library visitors. The interior of the building is divided into three main sections: 1—the study and reading area, located in the Islamic section; 2—the narrative area, situated in the Byzantine section; and 3—the gallery and art room, in the newly discovered section. As one employee declared, the building welcomes approximately 70 young visitors daily. The restoration and rehabilitation of this structure prioritises its efficient use by incorporating new facilities and equipment that cater to the needs of its visitors and users.

This project faced several challenges, the biggest of which was modifying the design, project schedule, and cost after discovering underground spaces during excavation. Other challenges include the lack of experience of workers and contractors in restoration. Many researchers highlighted that heritage building restoration projects have several difficulties, such as a lack of experience, qualified craftsmen, and necessary materials, which can impact the project, as mentioned in the study of Bullen and Love (2011) [52]. In addition, the closure and siege of the Gaza Strip also resulted in the delayed delivery of building materials, and some people from neighbouring areas intervened in the project.

5.2. Post-Occupancy Evaluation: User Experience

The al-Khader building has been thoughtfully rehabilitated as a children’s library, a function that aligns with the local community’s needs and surroundings, particularly in serving children, a vision that UNESCO underscored. Various researchers have underscored the significance of the heritage buildings’ new function aligned with the local community’s needs. The library’s mission is to foster cultural, artistic, and educational growth within the local community. It provides non-formal education programmes and library services to hundreds of children daily. The goal is to enhance their knowledge and information access through various activities, including reading, writing, scientific research, arts, and environmental studies. This daily engagement aims to cultivate a love for learning and exploration among the children. As the director of NAWA Culture and Arts Association, Reem Abu Jaber, stated about the al-Khader restoration and rehabilitation [21],

“The library is the jewel of our work at NAWA. Despite the difficult context in Gaza, it is spreading hope and positively impacting children’s learning and well-being. It is changing lives”.

This perspective aligns with the financier’s objective to support a comprehensive project that benefits the local community. As the supervisor of the al-Khader project expressed, “The financier aims to support a holistic project, especially since parts of it are in a conflict zone and at risk of collapse.” Moreover, the restoration was carried out to serve the community and was executed by a highly skilled restorer.

In the post-occupancy evaluation, the second author interviewed library employees for their opinions on reusing the al-Khader building as a children’s cultural library. The interviews were aimed to evaluate the project’s success and measure its impact on the children and surrounding community. The employees were also asked about the value of the project, and they responded that repurposing the building as a library was more valuable than using it as a tourist site, especially given the lack of a library in the area. One employee stated the following:

“The surrounding neighbourhood does not have a public library. Reusing the building for a library is a successful decision and a local community need”.

This new function also allowed the children to learn more about traditional buildings. In this way, this new function increased the value of this abandoned building. All the interviewed employees shared that the common feelings among the children while using the library are comfort, enjoyment, and harmony. Concerning the impact of the library on the surrounding neighbourhood community, another employee shared that the library in its early opening was not known to the nearby neighbourhoods; she mentioned one parent, saying,

“I am not optimistic that this building’s new function as a children’s library will really help and serve the community.”

However, after the awareness sessions, the children’s participation in activities, and leisure trips, these parents started to accept the new function of this traditional building. An employee noted that the shift in perception was mainly due to the positive feedback conveyed by the child visitors and their families about the new library. Furthermore, there has been a noticeable increase in children’s attendance since the library opened three years ago. Another parent respondent identified the nearby location as an important feature of the new library. Some parents also participated in library activities and even started parents’ clubs. When asked about the differences between using a library in a traditional building or a new concrete building, the employees generally preferred the traditional setup as it gives a feeling of oldness, originality, and pride in one’s identity and history. The traditional building also evokes elegance and enhances children’s knowledge about their culture and previous civilisations.

In the second part of the post-occupancy evaluation, the second author supervised interviews conducted by one of the library employees with children who were visitors. The interviews were conducted with 16 children who used the library, and all reported visiting the library once a week for leisure. For example, one of the children said the following:

“I love the place. I feel happy coming here with my friends to read, learn new things, and play in a friendly and safe environment”.

Most of the children loved the traditional arches and domes in the building, which made the library look distinguished and beautiful. They expressed their happiness when returning to their homes after visiting the library. In general, the interviews showed a high impact on the user’s perceptions of the effect of the adaptive reuse of the building as a library, its cultural and social sustainability, and its value to the surrounding community.

6. Results and Discussion: Project Goals Evaluation (Level of Success)

Generally, cultural heritage conservation projects align directly with Goals 11 (Sustainable Cities and Communities) and 8 (Decent Work and Economic Growth) [15,27].

Specifically, the UN-Palestine website states that the al-Khader project is supported through an initiative that aligns directly with Goal 4 (Quality Education) and Goal 17 (Partnerships for the Goals) of the SDGs [53]. In this study, the al-Khader building is connected directly and indirectly to 11 of the SDGs—directly with 7 goals (SDGs 4, 7, 8, 11, 12, 16, and 17) and indirectly with 4 goals (SDGs 1, 5, 9, and 13). The UN introduced targets for each goal to uncover the achievement of the SDGs in the local communities [54].

Table 2. Summary of the SDGs and their targets for the al-Khader building (Authors).

Link to SDGs	SDG Number	SDG Target	Summary of the SDG Targets
Directly	4	4.7	By 2030, ensure all learners acquire skills to promote sustainable development through education on sustainability, human rights, and cultural diversity.
	7	7.b	By 2030, enhance infrastructure and technology to deliver sustainable energy services to all developing countries, especially the least developed, small island, and land-locked states.
	8	8.9	By 2030, devise and implement policies to promote sustainable tourism that creates jobs and promotes local culture and products
	11	11.4	Strengthen efforts to protect and safeguard the world’s cultural and natural heritage.
	12	12.b	Develop and implement tools to monitor sustainable development impacts for sustainable tourism that creates jobs and promotes local culture and products
	16	16.7	Ensure responsive, inclusive, participatory, and representative decision-making at all levels.
	17	17.17 17.19	Encourage and promote effective partnerships among the public, private, and civil society sectors by leveraging their experiences and resources. By 2030, develop sustainable development progress measures beyond GDP and support statistical capacity-building in developing countries.
Indirectly	1	1.4	By 2030, ensure equal access to economic resources, services, and property for all, especially the poor and vulnerable.
	5	5.5	Ensure women’s full participation and equal leadership opportunities in all decision-making levels.
	9	9.1	Develop sustainable, resilient infrastructure to support economic growth and equitable access for all.
	13	13.b	Enhance climate change planning and management in vulnerable countries, focusing on women, youth, and marginalised communities.

demonstrates the relevant targets to achieve these goals in the case of the al-Khader library. Additionally, the project’s restoration and rehabilitation success and challenges have been evaluated in the context of the Quintuple Helix within the five social systems of the Quintuple Helix Model. This evaluation is relevant to the SDGs, both directly and indirectly, as follows:

• Government System: First, the restoration and rehabilitation decision-making included the needs of the surrounding local community for the new function. Second, the financer requested an integrated project to serve more locals and benefit from this new function of the al-Khader building. Third, the financial support comes from an external sponsor that covers the building restoration. However, the Ministry of Tourism and Antiquities has approved and overseen the restoration project. Fourth, the library management team is active and works on improving educational activities according to the needs of the children and the local community. However, these demands must be considered more to comply indirectly with Goal 9 (Industry, Innovation, and Infrastructure) and directly with Goal 12 (Responsible Consumption and Production).
• Education System: The new function of the building is to focus on the educational part involved in the non-academic learning process for school children. The new function as a library plays a significant role in promoting sustainability development and heritage preservation, which is directly connected with Goals 4 (Quality Education) and 17 (Partnerships for the Goals).
• Economic System: Generally, the cultural tourism industry has a positive effect on local communities by generating new employment opportunities, businesses, events, and attractions. This beneficial impact aids in diversifying the local economy and fostering growth. In the case of al-Khader, it provides a limited number of jobs, events, and local attractions. However, considering that the Gaza Strip is a conflict zone with complete blockade restrictions, it does not attract foreign tourists from other cities or countries. Nevertheless, this project offers supplementary services to the local community. This effort directly aligns with Goal 8 (Decent Work and Economic Growth), Goal 11 (Sustainable Cities and Communities), Goal 12 (Responsible Consumption and Production), Goal 16 (Peace, Justice, and Strong Institutions), and Goal 17 (Partnerships for the Goals).
• Civil Society System: The importance of reusing cultural heritage buildings had limited awareness at the beginning, showing the lack of community support and the lack of community engagement with library activities. Accordingly, the library management has hosted several community events and activities to promote the library. Furthermore, the library supports various activities and lectures and fosters parental involvement in decision-making. Also, the centre established a parent club to enhance the library’s programmes and activities for children. The centre has a substantial role in engaging with local communities. While the centre does not focus on empowering women and supporting local communities financially, it is not directly dedicated to these causes. These actions are aligned indirectly with Goal 1 (No Poverty) and Goal 5 (Gender Equality) and directly with Goal 8 (Decent Work and Economic Growth).
• Environmental System: The conservation of heritage buildings, such as the al-Khader building, can have a positive environmental impact by reducing pollution and preserving local materials and resources. Moreover, environmental considerations, such as energy efficiency, are considered during the conservation and maintenance process. For instance, the building utilises solar panels to conserve energy and lower electricity expenses. The al-Khader building has a beneficial environmental effect, directly contributing to achieving Goal 7 (Energy) and indirectly to Goal 13 (Climate Action).

In conclusion, this restoration and rehabilitation experience with this case study revealed several key points which can benefit future projects:

• Restoration process: Any additions, materials, utilities, or technical systems added to a traditional building must not detract from its appearance and perception of it. The conservation team, including workers, designers, and professionals, must be knowledgeable about the rules and techniques of conservation.
• In the context of building rehabilitation, a vital focus has been placed on meeting the social needs of the neighbouring communities. This emphasis on addressing these needs has added significant utility to these structures and firmly secured their long-term viability and endurance. Reusing these buildings for public use has produced a dual benefit—not only has it enriched the quality of life for local residents, but it has also played an essential role in elevating awareness regarding the critical importance of heritage conservation among local communities.
• Meeting the goals: This project shows uniqueness as buildings that enhance cultural sustainability by considering the community’s cultural and social needs, educating the local community’s children, and instilling positive values in them. The centre can create a positive effect that benefits the families and progressively influences the wider society. The al-Khader Library had a significant impact by directly and indirectly meeting the 11 goals of the SDGs.

7. Conclusions

The rehabilitation of heritage buildings in conflict zones presents numerous challenges, yet it also offers significant opportunities for sustainable development and cultural preservation. This study focused on restoring the al-Khader building in the Gaza Strip, a UNESCO-led project to preserve historical buildings and reuse them for community use. The al-Khader building rehabilitation significantly contributed mainly to social and cultural sustainability as one of the first preserved sites in Deir el-Balah, Gaza Strip.

Despite facing substantial obstacles, such as the lack of financial resources and skilled conservation professionals, the project transformed the al-Khader building into a vibrant community asset. Its restoration and rehabilitation have positively impacted heritage preservation and the local community, contributing to several Sustainable Development Goals (SDGs). Directly, the project aligned with SDGs 4 (Quality Education), 7 (Affordable and Clean Energy), 8 (Decent Work and Economic Growth), 11 (Sustainable Cities and Communities), 12 (Responsible Consumption and Production), 16 (Peace, Justice, and Strong Institutions), and 17 (Partnerships for the Goals). Indirectly, it supported SDGs 1 (No Poverty), 5 (Gender Equality), 9 (Industry, Innovation, and Infrastructure), and 13 (Climate Action). However, the project highlighted the need to improve alignment with these goals, which requires more consideration from the government and better management practices to ensure sustained success and impact.

The findings underscore the critical role of heritage building rehabilitation in fostering economic and social development within the framework of the Quintuple Helix Model, particularly in enhancing economic and civil society systems. However, to maximise the benefits of such projects, the contributions of government, education, and environmental systems need to be strengthened.

The al-Khader Library project, funded by external donors, has raised local awareness about the importance of preserving heritage buildings. Although the building’s current status remains uncertain due to ongoing conflict in Gaza, this study provides essential documentation of its condition as of 2023. The insights gained from this research highlight the potential of heritage rehabilitation projects to contribute to sustainable development in conflict-affected areas and underscore the need for continued support and investment in such initiatives.

By documenting and analysing the case study of the al-Khader Library rehabilitation in the Gaza Strip, this research provides valuable insights and recommendations for similar initiatives in conflict zones. Key findings highlight the importance of stakeholder engagement, local expertise development, cultural sensitivity, innovative funding methods, adaptive reuse, and sustainability integration. These elements are crucial for overcoming challenges such as limited resources and expertise and for ensuring the long-term viability and success of heritage rehabilitation projects. By fostering international collaboration, implementing strong monitoring and evaluation systems, promoting awareness and education, documenting success stories, and enhancing policy support, stakeholders can significantly contribute to the global request for heritage preservation and sustainable development, thereby aligning with several Sustainable Development Goals (SDGs).