## 1 Introduction
### Virtual Reality to Support the Design of Accessible Housing  
In recent years, virtual reality (VR) has emerged as a powerful tool across various fields of knowledge, enabling users to interact with three-dimensional computer-generated environments through immersive devices such as VR headsets, sensors, and haptic controllers [11,12]. This technology allows the recreation of realistic and controlled scenarios, where it is possible to simulate events, experience environmental conditions, and make informed decisions based on the visualization and immersion in these spaces [13,14]. In the field of Architecture, Engineering, and Construction (AEC), VR has proven effective in reducing the time and cost associated with design iteration phases, facilitating early project visualization and promoting collaboration among diverse stakeholders [15,16]. Virtual housing prototypes can be evaluated by professionals, users, and experts, allowing early feedback and significant improvements in quality and functionality [17]. Traditional design review processes often rely on 2D orthographic projections and renderings, which can be abstract and fragmented, requiring expert interpretation and potentially leading to miscommunication and rework [18]. Extended Reality (XR) technologies, such as VR and Mixed Reality (MR), offer a more intuitive means of design comprehension. For instance, studies using MR have shown effective communication of 85% of design information compared to 70% with 2D media, alongside enhanced understanding of material aesthetics [19]. Specifically, in the design of accessible housing, VR offers a valuable opportunity to experience spaces from the perspective of a person with a disability prior to construction [20,21]. By integrating three-dimensional architectural models into immersive environments--many of them developed using Building Information Modeling (BIM) tools--it is possible to validate both regulatory and functional aspects of accessibility, going beyond mere dimensional verification [22]. This capability is crucial as research in VR accessibility actively explores novel interaction techniques tailored to users with specific needs, considering trade-offs between accessibility, realism, and spatial awareness [23,24]. The inherent advantages of VR, including a wide field of view, high customizability, and an immersive sense of presence, make it a suitable platform for simulating how individuals,such as wheelchair users, experience and navigate designed spaces [25]. Moreover, the integration of XR with BIM is a significant and growing trend in the AEC sector. VR, in particular, is frequently paired with BIM in design and engineering case studies to enhance stakeholder collaboration and design understanding, thereby supporting more informed decision-making [26; 27; 28]. This allows for the simulation of assistive device maneuvers, identification of mobility barriers, and early detection of specific adaptation needs before project execution [29]. Additionally, virtual reality can facilitate co-design processes, enabling the active participation of people with disabilities in the evaluation and refinement of housing designs. Such early inclusion not only captures specific accessibility requirements but also promotes the development of personalized solutions that effectively address diverse individual needs and contexts [16; 30]. From this perspective, VR becomes not only a technical validation tool but also a means of empowering individuals who have historically been excluded from design processes, strengthening their sense of ownership and influence in decisions that affect their quality of life [19; 31]. Several initiatives aim to incorporate virtual reality as a method for evaluating accessible design. Immersive virtual environments stand out as an effective visual communication tool among designers, users, and AEC professionals [32]. However, technical, methodological, and implementation challenges persist, limiting the widespread adoption of VR in accessible design practices [33; 34].