Design Guidelines for Smart Nursing Homes in the Context of Aging

Abstract

With global aging accelerating, improving the efficiency and quality of elderly care is increasingly critical. This study proposes smart nursing home design guidelines to enhance care through smart device integration. The guidelines include two parts: smart device selection criteria, based on next-generation elderly needs identified via Japanese public surveys, and smart nursing home model templates, built upon existing Japanese housing standards. These guidelines provide practical recommendations on device usage, placement, and spatial optimization to improve accessibility and nursing efficiency. The study concludes by validating the effectiveness of the guidelines in addressing the requirements of the next generation of elderly people through a case study, which shows that although construction costs have increased by an average of 18.35%, the guidelines have ensured a safer, more comfortable, and technologically advanced nursing home environment.

1. Introduction

Aging is a global social phenomenon, and the health and well-being of the elderly in this context has become an essential social concern. Japan was one of the first countries in the world to enter an aging society. Japan’s aging situation has been on a long-term rapid rise since 1990. As of 2023, the number of elderly people aged 65 or older in Japan will be 36.23 million, accounting for 29.1% of Japan’s total population [1]. According to the data for 2021, there will be 25.809 million households with elderly people aged 65 or older, accounting for roughly half of the total of 51.914 million, and the proportion of these households is increasing year by year [2].

With regard to housing trends for the elderly in Japan, 82.1% of households with elderly people aged 65 or older live in owner-occupied housing, but the proportion of single elderly people living in owner-occupied housing is very low; most of the rest live in private rented housing. This characteristic, combined with the “Data on Annual Changes in the Structure of Households with Elderly People Aged 65 or Older”, shows that the number of single-person households in Japan has been increasing steadily since 1986 and, in general, the overall proportion of single elderly persons living as owners of owner-occupied housing has been high. However, trends show that the proportion of elderly people living as non-owners in other types of housing is increasing, particularly among households with people aged 65 and over. In the face of the global public crisis of aging, there is a necessity to safeguard the efficiency and quality of care of nursing homes for the elderly, in line with the trend of rising demand for such homes [3].

Japan’s existing design standards for housing for the elderly set out specific requirements in four main areas: barrier-free design, configuration of assistive facilities, optimization of interior layout, and design of toilets and bathrooms [4,5,6]. Barrier-free design emphasizes passageways and door widths suitable for wheelchairs, step-free designs, and ramps. Assistive facilities include the installation of handrails in corridors and bathrooms, non-slip floors, and switches and handles that are easy to operate. Interior layouts focus on the spaciousness of activity spaces and open-plan designs to enhance permeability and convenience, and in the toilets and bathrooms, non-slip floors, bathtubs of moderate heights, and other design elements are used to ensure the safety and comfort of the elderly. These standards aim to comprehensively improve the safety and convenience of the living environment for the elderly and to promote the improvement of their quality of life.

Japan proposes the “Next-Generation Elderly Home”, which refers to housing that can be used by the elderly with barrier-free design, taking into consideration their needs for “low-cost housing that emphasizes freedom of living and provides support” in order to achieve the next-generation development goal of “providing targeted housing for the elderly for 4% of the elderly population by 2040”. However, the demands of the elderly are not limited to “freedom of life” and “low-cost housing”. It is necessary to consider the “next-generation housing requirements” of the elderly on the basis of barrier-free design and to design the “Next-Generation Elderly Home” based on the fulfillment of these requirements [7].

Using smart devices from the Internet of Things (IoT) and Information and Communication Technology (ICT) in smart houses to solve housing problems is becoming more common, and the “smart care” model of employing smart devices in nursing homes is attracting attention [8,9,10,11]. The use of smart devices not only enhances the convenience of nursing facilities but also brings about significant improvements in four key categories of care: safety monitoring, health management, social interaction, and mobility assistance. First, smart sensors and remote monitoring systems enhance safety by detecting elderly activity, fall risks, and emergencies in real-time, ensuring rapid response [12]. Second, in health management, smart devices collect biodata, enable personalized care, and support preventive medicine [13]. Third, for social interaction, they facilitate remote communication, virtual companionship, and activity planning, reducing loneliness [14]. Finally, in mobility assistance, technologies like smart wheelchairs, walking aids, and voice control improve autonomy, lessen caregiver dependence, and enhance daily quality of life [15]. The use of smart devices in nursing homes not only improves the efficiency of care services but also responds to the “2025 problem” (super-aging society) [16] by providing innovative solutions to the strain on care resources and the shortage of healthcare workers, thus improving the quality of life of the elderly and promoting the development of smart aging.

In summary, although the existing design standards for elderly housing in Japan already have high requirements for accessibility and safety, there are still limitations, such as insufficient personalized adaptability, lack of smart devices, and insufficient attention to the design of soft environments (Figure 1). First, current standardized designs focus more on universality and less on adaptability for elderly people with different health conditions and lifestyles. Existing standards do not yet adequately take into account these individualized needs [17,18]. Second, although technologies have great potential for improving the quality of life of the elderly, current design standards pay less attention to the “smart care” model, failing to incorporate them into housing design specifications and restricting the application of smart devices in the elderly living environment [19,20,21]. Finally, existing standards focus mainly on the modification of hardware facilities, while less consideration is given to the design of soft environments, such as the psychological needs of the elderly, community support, and social interaction, which fails to effectively promote the social integration and psychological well-being of the elderly [22,23]. To ameliorate these limitations, Japan’s design standards for housing for the elderly should further expand adaptive design, enhance the application of smart technologies, and strengthen the creation of soft environments in order to build more comprehensive and adaptive age-friendly living environments [24,25].

At the same time, although the nursing-related industry promotes the use of ICT and other technologies, this is limited to the use of medical equipment and the like, and the specific design of smart nursing homes based on home devices remains an unexplored field, with no examples of existing regulations to which reference can be made [26]. Therefore, this study considers it necessary to propose guidelines for the design of smart nursing homes to remedy the shortcomings in Japanese design labeling.

Housing design standards for elderly people around the world usually include elements such as barrier-free design, health promotion, social interaction, and community support. In the United States, “A Guide to Aging in Place Design” emphasizes barrier-free design and supportive communities [27]; in the United Kingdom, “Housing for Older People Design Standards” and in Sweden, the “Swedish Social Services Act (Socialtjänstlag)” emphasize social interaction spaces [28,29]; in Germany, “Regulation on Personnel Requirements for Care Homes” puts forward the concept of aging in place [30] and China’s “Code for Design of Residential Building for the Aged” also pay attention to barrier-free design, the construction of health services, and the concept of aging in place [31]. Overall, the limitations of the standards in each country generally include insufficient individualized needs, insufficient application of smart technologies, and neglect of the soft environment. In addition to this, the difficulty of policy implementation is an issue that needs to be addressed due to the different aging processes in each country.

The smart nursing home design guidelines based on the Japanese design standards are more applicable to countries and regions where the problem of aging is becoming more serious (e.g., Germany, China, and some other East Asian countries), where there is an urgent need to improve and optimize the existing care and living facilities for the larger elderly population [32]. The concept of “aging in place” is also emphasized in the standards of these countries in order to reduce the pressure on society. Meanwhile, countries and regions such as China, India, and Singapore are vigorously promoting the development of smart cities and smart healthcare [33]. These countries have large investment and development potential in both infrastructure construction and smart technology. Smart nursing home design guidelines provide a reference for these countries, which can be combined with other construction projects of smart cities (e.g., smart health, smart community, etc.).

In this study, smart nursing home design guidelines that satisfy the design criteria for elderly housing are proposed. In this study, firstly, requirements for elderly housing are summarized based on the Japanese public awareness survey, and based on the requirements, smart device selection criteria and smart devices to meet the requirements are compiled. Then, floor plan examples of next-generation nursing home types in line with the design standards for elderly housing and the needs of next-generation housing are discussed, the problems and shortcomings solved by the existing design standards are clarified, and the smart nursing home model templates are formed. Finally, the smart device selection criteria are combined with the smart nursing home model templates to propose smart nursing home design guidelines, which clarify the devices used in next-generation housing for the elderly, the location of the devices, and how the devices are used (Figure 1). This study innovatively incorporates smart technology as a core element to move from reactive care to proactive and technology-assisted aging solutions.

This study promotes the application of smart building in nursing homes, makes smartness a core design element, and provides a systematic framework and design guidelines to help urban planners, architects, and policymakers optimize building standards for nursing homes. The research optimizes spatial layout, improves care convenience, and enhances the scientific and adaptive nature of building design, especially in the field of modular buildings, to provide feasible solutions. At the same time, the study promotes the deep integration of smart home technologies and health monitoring systems, facilitates cross-border cooperation among the architecture, technology, and healthcare industries, and assists in the construction of smart aging environments.

2. Theoretical Concept and Methodology

In order to meet the demands of the elderly in the context of aging, this study argues that the smart nursing home design guidelines contain two parts: the smart device selection criteria and smart nursing home model templates. In the study of smart device selection criteria, it is necessary to clarify the current requirements of the elderly and the smart devices applicable to elderly housing in a demand-oriented manner; the study of smart nursing home model templates is based on the existing design standards and the requirements of the next generation of nursing homes. After developing the smart nursing home design guidelines, this study was conducted to clarify the effectiveness of using the smart nursing home design guidelines through a case setting. The steps are as follows (Figure 2):

• Study of smart device selection criteria based on the next-generation elderly’s requirements: Awareness surveys of the Japanese public were conducted to comprehensively summarize the core needs of the elderly for housing, including safety, convenience, medical support, and psychological comfort. Based on the results of the survey, the smart devices required to satisfy these requirements were sorted out, and the types of devices with practical application value were screened and formed into smart device selection criteria. The smart device selection criteria were combined with the subsequent smart nursing home model templates to form the smart nursing home design guidelines.
• Study smart nursing home model templates based on the next-generation housing requirements: Explore the requirements for next-generation nursing home model types that satisfy the design standards for elderly housing, analyze the role of the existing design standards, the problems they solve and their limitations, and draw next-generation nursing home model types that satisfy both the existing design standards and the requirements for next-generation nursing home and serve as templates for smart nursing home model types. The smart nursing home model templates and the smart device selection criteria constitute the Smart Nursing Homes Design Guidelines. The next-generation nursing home model type serves as a template for the smart nursing home, and smart devices are incorporated into the house type to achieve the goal of smart nursing.
• Proposing Design Guidelines for smart nursing homes: Summarize the study results on the arrangement of household types and smart devices of next-generation nursing homes, clarify the templates of smart nursing home models and the criteria for the selection of smart devices (including the functional positioning, selection criteria, and matching with actual use scenarios), and formulate the guidelines for the design of smart nursing homes. The design guidelines will be used in subsequent smart nursing home design cases to validate the use of the smart nursing home design guidelines.
• Case study of smart nursing home design: Based on the smart nursing home design guidelines, the selected smart devices are combined with the house model templates to clarify the specific functions, placement, and usage of each device. By simulating the actual use scenarios, it verifies the matching degree and application effect between the smart devices with the house model design.

The research data used in this study are from the Dai-ichi Life Economics Research Institute’s publicly available Japan Public Awareness Surveys, including the February 2008, September 2012, December 2018, and September 2022 surveys. The surveys were conducted using the mail-in method and covered 1010 (2008), 1000 (2012), 1000 (2018), and 1000 (2022) men and women between the ages of 20 and 89 years old, respectively. The data were screened, and the average effective recall rate for the four surveys was about 94%.

This study uses descriptive statistical analysis to conduct a preliminary analysis of this research data in order to reveal the characteristics of the next generation elderly’s requirements. Based on the distribution pattern in order to determine the degree of concentration and tendency of the data, the requirements are summarized.

While many realistic constraints have been considered in this study in developing design guidelines for smart nursing homes, there are still some constraints that have not been adequately considered or need to be further explored in the future, including the following:

• Uncertainty of changing demand: As technology advances, lifestyle changes, and cultural differences occur, the demand for smart nursing homes for older adults will change. This study minimizes this uncertainty by using data spanning a period of about 12 years.
• Device Reliability and Maintenance Costs: The study focuses on device selection and configuration but does not delve into the stability, failure rate, and maintenance needs of the devices in long-term use, nor does it address the mechanism for updating the devices.
• Cross-country adaptation and policy and regulatory impact: Although the adaptation of smart nursing homes in different countries is considered, the impact of national aging policies and data privacy regulations on the construction of smart nursing homes is not explored in detail, especially health data management and privacy restrictions.

The Smart Nursing Home Design Guidelines ultimately aim to provide comprehensive guidance to relevant designers and decision-makers to help them rationally configure smart devices, optimize design solutions, promote the conceptualization of smart nursing homes from conceptualization to practice, and facilitate the comprehensive development of smart nursing homes.

3. Study on Smart Device Selection Criteria Based on the Next-Generation Elderly’s Requirements

Japan’s Next-Generation Elderly Home is a new housing model for the future of an aging society that aims to improve the safety, convenience, and comfort of elderly people [34,35]. The design combines the principles of accessibility and universal design, and uses facilities such as steplessness, wide doorways, and automatic doors to reduce mobility barriers and improve ease of living and medical support. The Next-Generation Elderly Home also features complex health and wellness functions. At the same time, the house type is designed to be flexible, and the furniture and space layout can be adjusted to suit the demands of the elderly at different phases of their lives in accordance with their changing physical conditions. The Japanese government and construction industry are promoting the standardization of this housing model to meet the challenges of an ultra-elderly society and to provide sustainable housing solutions.

In addition, considering the environment for end-of-life care for the elderly in 2040, public awareness surveys conducted in February 2008, September 2012, December 2018, and September 2022 show that 20–40-year-olds are more concerned about the place of end-of-life care and believe that a place where there are adequate medical and nursing care services and where elderly people have a close relationship with other people is the most suitable place for end-of-life care [36,37,38,39]. Therefore, in addition to the existing requirements of “daily care”, “privacy”, “safety and convenience”, “daily recreation”, “family care”, and “self-worth realization”, “next-generation elderly” also need to consider the requirements of “ family care” and “self-worth realization”. Therefore, when designing housing for the next-generation elderly, it is necessary to integrate the requirements of “next-generation elderly housing” with the programs needed for “designing end-of-life home care”.

Based on the compilation of the contents of the Japanese Housing Design Guidelines for the Elderly and the contents of hospice care, the study summarized the requirements of the elderly in the next generation based on the behavioral characteristics and living demands of the elderly population in the next generation (

Table 1. Next Generation Elderly’s Requirements.

Types	Content	How Requirements Are Satisfied
Family Care	Easy for family members to monitor the patient’s condition	Using smart devices (monitoring sensor devices, data transmission devices)
	Elders can spend more time with family members	Use of smart devices (communication devices, data transmission devices)
Daily Care	Efficient care	Rational floor plan, efficient care flow, use of smart devices
	Rapid access to physical data of elders	Use of smart devices (monitoring sensor devices)
	Care data recording and statistics	Use of smart devices (data analysis devices, data transmission devices)
Privacy and Security	Lifestyle can be maintained	Rational floor plan layout, layout of daily equipment
	Privacy is maintained when there are visitors	Rational floor plan layout, use of smart devices (smart curtains)
Safe and Easy Mobility	Easy access from the treatment area to the restroom	Rational floor plan layout
	Easy access from the treatment area to the outside	Rational floor plan layout
	Mobility safety is assured without steps or obstacles	Reasonable floor plan layout, use of smart devices (smart curtains)
	Activities of daily living can be accomplished in a small area	Reasonable floor plan layout, layout of daily devices, use of smart devices
	The function of the living room is maintained as a communal and reception space	Reasonable floor plan layout, use of smart devices
	Bathroom and toilet facilities are easily accessible	Reasonable floor plan layout, efficient life flow, use of smart devices
Daily Recreation	Daily recreation with other seniors, family members, etc.	Rational floor plan layout, use of smart devices (remote interactive devices, AR, VR, etc.), rational community planning
Achieving Value	Participation in creative activities and realization of the social value of elders	Use of smart devices (smartphones, AR, VR, etc.), rational community planning

Source: Self-organized.

).

In the housing for the elderly of the next generation, the use of smart devices in the mode of “smart care” can meet more housing demands of the elderly and solve the problems of housing the elderly. Therefore, the study will select the smart devices available in the market based on the elderly groups that are applicable to the Japanese serviced residences for elders and fee-based nursing homes. The fee-based nursing homes and serviced residences for elders are nursing homes that do not take into consideration the physical condition of the elderly residents. The fee-based nursing homes are suitable for all kinds of elderly people; the serviced residences for elders are suitable for singles or couples over or under 60 years of age who need care and attention. Therefore, when considering smart devices, one needs to consider the types of devices that are suitable for the majority of the elderly population.

The known smart devices on the market incorporate various elements based on their uses, which are broadly categorized into three types. First, sensors that detect human movement, which are used for human monitoring, and so on. Sensors acquire information in the following ways: (i) wearable devices worn by the user, (ii) communication devices operated by the user, and (iii) pre-installed devices.

The second is the transmission and sharing of user information. In recent years, the development of IoT technology and the popularity of smartphones have made it easier to share information with remote locations. The ability of smart devices to transmit information can be categorized into (i) real-time uploading of data and sharing them with other devices or services (real-time uploading), (ii) not actively uploading but available for the user to manually send or receive information (non-initiated uploading), and (iii) running independently without networking or only localized interaction (independent operation).

The third element is accessibility and operability, such as the incorporation of apps to improve the operability of common appliances and to improve the health of users, which includes health guidance utilizing AI and other health guidance installed in household appliances, as well as voice operation that is effective for users with impaired vision.

Considering the above 3 types of smart devices, their advantages in this study are divided into three main categories: security, convenience, and personalized demand. Based on the advantages of these three categories, the smart devices that can be used in the housing for the elderly of the next generation are summarized as shown in

Table 2. Device Selection.

Location	Name	Usage	Advantage
Bedroom	Ururu Sarara X AN22YRS-W (DAIKIN, Osaka, Japan)	Air conditioner (6 tatami mats)	Convenience (easy control)
	LDA9L-G/D-86AITG (Iris Ohyama, Sendai, Japan)	Light bulbs	Personalized demand (low blue light, eye protection design)
	CL8D-6.0AIT (Iris Ohyama, Sendai, Japan)	Ceiling light (8 tatami mats)	Personalized demand (low blue light, eye protection design)
	INTIME2000i (Paramount Bed Co., Tokyo, Japan)	Electric recliner bed	Safety (fall prevention design)
	CALM-LITE (Paramount Bed Co., Tokyo, Japan)	Mattress	Personalized demand (spinal support, breathable and anti-bedsore, model compatibility with electric recliner bed)
	Active Sleep ANALYZER (Paramount Bed Co., Tokyo, Japan)	Sensor	Safety (smart alarm system)
Living room	DOSITEL (HITACHI, Tokyo, Japan)	Monitoring service	Convenience (easy control)
	Google Nest Mini (Google, Mountain View, CA, USA)	Smart Speakers	Convenience (easy control)
	Chromecast (Google, Mountain View, CA, USA)	Streaming services	Safety (wide-area monitoring)
	4T-C43DN2 (SHARP, Osaka, Japan)	TVs	Convenience (easy control); Personalized demand (low blue light, eye protection design)
	Roomba i3+ (iRobot, Bedford, MA, USA)	Robot vacuum cleaners	Convenience (easy control)
	LCD light control film (Toppan Printing Co., Tokyo, Japan)	Smart window	Convenience (easy installation); Safety (seismic protection)
	Ururu Sarara X (DAIKIN, Osaka, Japan)	Air conditioner (6 tatami mats)	Convenience (easy control)
Bathroom and Dressing room	BD-SX110FL (HITACHI, Tokyo, Japan)	Washer/dryer	Personalized demand (automatic washing and drying, sterilization mode)
	GH-HK245ZW (PURPOSE, Numazu, Japan)	Water heater	Convenience (easy control); Safety (temperature control to prevent scalding)
	TC-921ZT-WID (PURPOSE, Numazu, Japan)	Remote controls for heat source units for water heaters and hot water heating	Convenience (easy control); Safety (temperature control to prevent scalding)
	FY-13UG7E (Panasonic, Osaka, Japan)	Electric bath ventilation dryer	Convenience (easy control); Personalized demand (warm air mode)
	HBF-228T (Omron, Kyoto, Japan)	Scales	Convenience (voice prompt)
Kitchen	AX-XW600 (SHARP, Osaka, Japan)	Microwave oven	Convenience (voice prompt); Safety (temperature control to prevent scalding)
	SJ-GA50E (SHARP, Osaka, Japan)	Refrigerator	Personalized demand (low energy consumption, quiet operation)
Entrance	VS-HC400K (Panasonic, Osaka, Japan)	Door camera kit with monitor	Safety (fraud prevention, smart alarm system)
	ES-F500D (EPIC, Seoul, Republic of Korea)	Smart locks	Safety (fraud prevention, smart alarm system)

Source: Based on publicly available information of DAIKIN (Osaka, Japan), Iris Oyama (Sendai, Japan), Paramount Bed Corporation (Tokyo, Japan), Hitachi (Tokyo, Japan), Google (Mountain View, CA, USA), SHARP (Osaka, Japan), iRobot (Bedford, MA, USA), Toppan Printing Co (Tokyo, Japan), PURPOSE (Numazu, Japan), Panasonic (Osaka, Japan), omron (Kyoto, Japan), and EPIC (Seoul, Republic of Korea).

. The safety and convenience advantages correspond to Safe and Easy Mobility proposed in Table 1, and the personalization demands include Family Care, Daily Care, Privacy and security, Daily Recreation, and Achieving Value proposed in Table 1.

The study concluded that the selection of housing devices for the elderly is based not only on the functionality of each smart device but also on its operability. However, with regard to the operability factor, the degree of difficulty in operating the device varies according to the user’s experience (especially if the user is an elderly person), and, therefore, an indicator is needed to evaluate the user’s ability to operate the device when selecting a smart device.

Therefore, before summarizing the smart devices used in the next-generation nursing homes, this study evaluated the devices using “operability” as the main evaluation index (

Table 3. Smart Device Operability.

Location	Name	Smartphone Controls	Speaker Controls	Other Controls
Bedroom	Ururu Sarara X (DAIKIN, Osaka, Japan)	⃝	⃝	Remote Controls
	LDA9L-G/D-86AITG (Iris Ohyama, Sendai, Japan)	⃝	⃝	Switch/Remote Controls
	CL8D-6.0AIT (Iris Ohyama, Sendai, Japan)	⃝	⃝	Switch/Remote Controls
	INTIME2000i (Paramount Bed Co., Tokyo, Japan)	⃝		Remote Controls
	CALM-LITE (Paramount Bed Co., Tokyo, Japan)			No other Controls
	Active Sleep ANALYZER (Paramount Bed Co., Tokyo, Japan)	⃝		Remote Controls
Living room	DOSITEL (HITACHI, Tokyo, Japan)	⃝		No other Controls
	Google Nest Mini (Google, Mountain View, CA, USA)		⃝	Main unit Controls
	Chromecast (Google, Mountain View, CA, USA)	⃝		No other Controls
	4T-C43DN2 (SHARP, Osaka, Japan)		⃝	Remote Controls
	Roomba i3+ (iRobot, Bedford, MA, USA)	⃝	⃝	Button Controls
	LCD light control film (Toppan Printing Co., Tokyo, Japan)			Switch
	Ururu Sarara X (DAIKIN, Osaka, Japan)	⃝	⃝	Remote Controls
Bathroom and Dressing room	BD-SX110FL (HITACHI, Tokyo, Japan)			Switch
	GH-HK245ZW (PURPOSE, Numazu, Japan)			No other Controls
	TC-921ZT-WID (PURPOSE, Numazu, Japan)	⃝		Switch
	FY-13UG7E (Panasonic, Osaka, Japan)			Switch
	HBF-228T (Omron, Kyoto, Japan)			No other Controls
Kitchen	AX-XW600 (SHARP, Osaka, Japan)	⃝		Voice Controls
	SJ-GA50E (SHARP, Osaka, Japan)	⃝		Commonly utilized
Entrance	VS-HC400K (Panasonic, Osaka, Japan)	⃝		Switch
	ES-F500D (EPIC, Seoul, Republic of Korea)	⃝		Commonly utilized

⃝ indicates available for control. Source: based on publicly available information of DAIKIN (Osaka, Japan), Iris Oyama (Sendai, Japan), Paramount Bed Corporation (Tokyo, Japan), Hitachi (Tokyo, Japan), Google (Mountain View, CA, USA), SHARP (Osaka, Japan), iRobot (Bedford, MA, USA), Toppan Printing Co. (Tokyo, Japan), PURPOSE (Numazu, Japan), Panasonic (Osaka, Japan), omron (Kyoto, Japan), and EPIC (Seoul, Republic of Korea).

). The selected smart devices have two or more control methods, and their operability is better than that of other smart devices of the same type on the market.

This chapter summarizes 3 categories of criteria for smart device selection in the smart nursing home, including a way to detect human movement, the capability of transferring and sharing user information, accessibility, and operability. These 3 categories of criteria constitute the smart device selection criteria. By combining them with the smart nursing home model templates proposed in the next chapter, they together constitute the smart nursing home design guidelines.

4. Study on Smart Nursing Home Model Templates Based on the Next-Generation Housing Requirements

Considering the design requirements for “next-generation housing for the elderly”(Next Generation Housing Requirements) in Japan, i.e., “accessibility and universal design principles”, “complex recreational functions”, and “flexibility in house type design”, this study proposes 2 different house type models (Figure 3 and Figure 4), taking into account the requirements for the scale of elderly housing in existing Japanese regulations.

The model shown in Figure 3 is named the “LDK-integrated model”, which combines the usual living space and bedroom area in the same space. The advantage of this model is that it facilitates care for the elderly. Even if they are bedridden, family members and caregivers can easily observe the condition of the elderly who need care.

In addition to this, the shorter distance between the dressing room and the bedroom also contributes to the living and effective care of the physically disabled elderly. The house model generally complies with the regulations and standards related to housing for the elderly in Japan, while the turning and steering spaces in the kitchen, living room, and dressing room make it dimensionally suitable for wheelchair users as well (meeting the design standards for housing for the disabled).

There are several disadvantages in the LDK-integrated model that hinder effective caregiving. First, a blind spot exists, preventing healthcare workers from providing timely assistance in emergencies; second, the lack of a wall between the bedroom and the living room compromises privacy; third, the long distance between the entrance and the bedroom makes movement difficult; and lastly, the lengthy flow of housekeeping services creates inconvenience for caregivers.

The house type shown in Figure 4 is the “LDK-continuous model”, which has a wall between the usual living space and the bedroom. The advantage of this model is that the bedroom and the living room are separate, which safeguards the function of the living room. The separation of the bedroom and the living room allows the elderly to live a more dynamic life, cope with visitors, and carry out daily activities (e.g., shortening the flow of housework). The presence of a dedicated therapeutic space also maintains privacy, while the proximity of the bedroom and the toilet has the advantage of preventing accidents, e.g., falls caused by walking at night.

However, similar to the LDK-continuous model, this model also has disadvantages. First, the living space is smaller; second, the bathrooms and toilets are located far apart; and third, the longer flow lines for caregivers make it more troublesome and difficult to attend to the elderly, especially when providing care.

Overall, the LDK-integrated model and the LDK-continuous model have multiple advantages over traditional nursing homes. The LDK model improves space utilization by combining living, dining, and kitchen into an open-plan space, which is particularly suitable for small apartment senior living facilities in Japan. The open-plan design enhances visibility between caregivers and the elderly, which contributes to social interaction and alleviates loneliness. The LDK-integrated model is particularly helpful for elderly people with limited mobility by shortening the flow of life and reducing long-distance mobility, facilitating their daily activities. The LDK-continuous model, on the other hand, is more suitable for the elderly who are bedridden for long periods of time, with a dedicated therapy space to protect privacy and a bedroom adjacent to the bathroom to reduce toileting difficulties.

To address the shortcomings of the currently identified LDK-integrated model and LDK-continuous model, the study considers remedying these shortcomings by incorporating the smart devices identified in Table 2 to meet the needs of “next-generation elderly housing” and “designing end-of-life home care”. The LDK-integrated model and LDK-continuous model can be used as templates for smart nursing home models, as they can satisfy both the existing design standards and the requirements for next-generation nursing homes. Combined with the smart device selection criteria, they form the Smart Nursing Home Design Guidelines, which guide the design of smart nursing homes on the one hand and the selection, installation, and use of smart devices on the other.

5. Design Guidelines for Smart Nursing Homes

The Smart Nursing Home Design Guideline combines the smart nursing home model templates (

Table 4. Design Guidelines for Templates in Smart Nursing Homes.

House Models	Overview	Space Layout Requirements	Aging-Friendly Design Rules	Disadvantages
LDK-integrated model	LDK-integrated models refer to integrated living room-dining room-kitchen (LDK) models, which are designed to optimize the use of space and improve living comfort.	Ensure that the living room, dining room, and kitchen areas are open and connected to improve mobility.	1. Channel width: ≥900 mm. 2. Barrier-free design: no height difference on the ground, with a gentle slope in the bathroom. 3. Safety handrails: handrails are installed in the bathroom, corridor, and bedside. 4. Bathroom, dressing room, and living room set rotary space diameter: ≥1500 mm. Bathroom interior space: ≥1500 mm × 1500 mm. 5. Toilet set rotary space diameter: ≥1400 mm. Toilet internal square space: ≥1500 mm × 1500 mm. 6. Door width: single door ≥ 800 mm, double doors ≥ 850 mm.	1. There is a blind spot in the room, which makes it impossible for healthcare workers to accurately assist the elderly immediately after an emergency occurs. 2. There is no wall between the bedroom and the living room, making it difficult to ensure privacy. 3. The distance between the entrance and the bedroom is far and not easy to move. 4. The long flow of housekeeping services makes it inconvenient for caregivers to work.
		Avoid narrow passageways to ensure wheelchair accessibility.
		Have at least one bedroom adjacent to the LDK area for easy access by the caregiver.
LDK-continuous model	LDK-continuous models refer to living room–dining room–kitchen (LDK) continuous models, which are designed to optimize the care environment for the elderly and improve the ease of living.	Keep the living room, dining room, and kitchen connected to form a smooth line of life and activity.		1. Smaller living space. 2. Bathrooms and toilets are far apart. 3. A long flow for caregivers to take care of the elderly, which may be troublesome and difficult.
		Adjustable partitions to enhance spatial flexibility.
		Provide barrier-free access for wheelchairs and walkers.

Source: Self-organized based on the Elderly Welfare Law, Elderly Housing Law, Intermediate Care Insurance Law, and other laws in Japan.

) and smart device selection criteria (

Table 5. Smart Device Selection Criteria in the Smart Nursing Home.

Location	Device Type	Ways to Detect Human Movement	Capability of Transmission and Sharing of User Information	Operability	Correspondence with the Smart Nursing Home Template
Bedroom	Air Conditioner	pre-installed devices	non-initiated uploading	Smartphone Controls, Speaker Controls, Remote Controls	/
	LED bulbs	pre-installed devices	non-initiated uploading	Smartphone Controls, Speaker Controls, Switch/Remote Controls	/
	Ceiling light	pre-installed devices	independent operation	Smartphone Controls, Speaker Controls, Switch/Remote Controls	/
	Electric Nursing Bed	pre-installed devices	independent operation	Smartphone Controls, Remote Controls	LDK-integrated model and LDK-continuous model: long caretaking flow line
	Sleep aid lamps	pre-installed devices	independent operation	/	/
	Sleep analysis devices	pre-installed devices	real-time uploading	Smartphone Controls, Remote Controls	LDK-integrated model and LDK-continuous model: long caretaking flow line
Living room	Smart Guardianship Sensor	wearable devices worn by the user	real-time uploading	Smartphone Controls	LDK-integrated model: blind spot; LDK-continuous model: long caretaking flow line
	Smart Speaker	communication devices operated by the user	real-time uploading	Speaker Controls, Main Unit Controls	/
	Smart Screen Projection Devices	communication devices operated by the user	non-initiated uploading	Smartphone Controls	/
	TV	pre-installed devices	non-initiated uploading	Speaker Controls, Remote Controls	/
	Sweeping Robot	pre-installed devices	real-time uploading	Smartphone Controls, Speaker Controls, Button Controls	LDK-integrated model: long caretaking flow line
	Smart Window Film	pre-installed devices	non-initiated uploading	Switch	LDK-integrated model: difficulty in ensuring privacy; LDK-continuous model: long caretaking flow line
	Air Conditioner	pre-installed devices	non-initiated uploading	Smartphone Controls, Speaker Controls, Remote Controls	/
Bathroom and Dressing room	Washing and drying machine	pre-installed devices	independent operation	Switch	LDK-integrated model: long caretaking flow line
	Water Heater	pre-installed devices	non-initiated uploading	/	LDK-integrated model: long caretaking flow line
	Heaters Smart Remote Control	pre-installed devices	non-initiated uploading	Smartphone Controls, Switch	LDK-integrated model: long caretaking flow line
	Electric Bathroom Heater	pre-installed devices	independent operation	Switch	LDK-integrated model: long caretaking flow line
	Smart Scale	wearable devices worn by the user	real-time uploading	/	LDK-continuous model: long caretaking flow line
Kitchen	Microwave oven	pre-installed devices	independent operation	Smartphone Controls, Voice Controls	/
	Refrigerator	pre-installed devices	independent operation	Smartphone Controls, Commonly utilized	/
Entrance	Smart Camera	communication devices operated by the user	real-time uploading	Smartphone Controls, Switch	LDK-integrated model: blind spot; LDK-continuous model: long caretaking flow line
	Smart Door Lock	communication devices operated by the user	real-time uploading	Smartphone Controls, Commonly utilized	LDK-integrated model: Difficulty in ensuring privacy

Source: Self-organized based on publicly available information of DAIKIN, Iris Oyama, Paramount Bed Corporation, Hitachi, Google, SHARP, iRobot, Toppan Printing Co, PURPOSE, Panasonic, omron, and EPIC.

). Based on the LDK-integrated model and LDK-continuous model templates of smart nursing homes, the selection and optimization of smart devices are proposed based on their spatial characteristics and aging needs (Figure 5). The devices are categorized according to wearable devices worn by the user (user-worn devices), communication devices operated by the user (user-operated devices), and pre-installed devices. Their application value in nursing home design is analyzed in light of their information transmission and operation modes.

In the LDK-integrated model, the main problems include blind spots that make it difficult to respond to emergencies in a timely manner, the lack of a partition between the bedroom and the living room that affects privacy, the distance between the entrance and the bedroom, which does not allow for easy mobility, and the long flow of housekeeping services that reduce the efficiency of the caregiving process. To optimize this house type, it is recommended to use smart guardianship sensors (user-worn devices) to upload the user’s status in real-time and reduce the problem of blind spots in the line of sight. Smart cameras (user-operated devices) are installed in the entrance area to provide remote monitoring functions and enhance security, and smart window film (pre-installed devices) is installed between the bedroom and the living room to provide flexible switching between privacy and openness by adjusting the transparency. In addition, installing smart cameras and smart door locks at the entrance not only enables remote visitor management but also enhances overall security and improves the convenience of living for the elderly.

In the LDK-continuous model, the main challenges are smaller living spaces, farther spacing between bathrooms and toilets, and longer care flow lines that may increase the workload of nursing staff. The optimized solution includes the introduction of smart monitoring sensors that transmit real-time information on the status of the elderly to help caregivers respond in a timely manner, smart window film that can be used for flexible spatial partitioning, which not only protects privacy but also facilitates observation by caregivers, and a smart weighing scale (user-worn devices) that is linked to the health management system, which facilitates long-term health monitoring. In addition, installing smart cameras and smart door locks at the entrance not only realizes remote visitor management but also enhances overall security and improves the convenience of living for the elderly.

From a comprehensive viewpoint, the rational configuration of smart devices can make up for the deficiencies of different models and improve the maintenance efficiency and quality of life of the smart nursing home. The next step is to verify the effectiveness of the smart nursing home design guidelines through a design case.

6. Smart Nursing Home Design Case

According to the smart nursing home design guidelines, the smart nursing home will be based on the smart nursing home house model template mentioned in Figure 3 and Figure 4, and the shortcomings of these two types of house models will be compensated through the use of smart devices (Table 3). Figure 6, Figure 7, Figure 8 and Figure 9 analyze the smart devices in terms of their specific location and usage to form a case study of smart device installation within the smart nursing home.

LDK-integrated model: Due to the design of the structure, LDK-integrated models have blind spots in front of kitchens, bathrooms, and front doors, which can be used to share information and respond in the event of an emergency by installing a room inspection sensor “CPI Series” (Figure 7). In addition, the distance between the entrance and the bedroom is automatically displayed by a camera device on the door and handled remotely, and smart locks enable residents with declining physical functions to cope smoothly with visitors.

The LDK-integrated model case was selected for a detached house in Mawaoka City, Tochigi, Japan (Figure 10) [40]. The interior area of this case is about 80 square meters, and the bedroom is in Japanese style. It was completed in 2023, and the facilities related to aging were retrofitted at a later stage. The bathroom, toilet, and other corner spaces are in accordance with the Japanese nursing home design standards. The cost of retrofitting, excluding equipment, was approximately 1.5 million JPY, accounting for 7.14% of the original construction cost of 21 million JPY. By installing smart devices such as inspection sensors at a later stage, it will be possible to respond quickly in the event of an emergency to ensure the safety of users. The cost of the devices is about 1.9 million JPY, and the cost of the network monitoring service is about 20,000 JPY/month. The total cost has increased by 16.19%.

LDK-continuous model: Disadvantages of the LDK-continuous models include small space and difficulty in taking care of the elderly. These problems can be solved using smart window films/windows. By installing smart window films/windows on the partition between the bedroom and the living room, when the window films/windows are opaque, they can be used as a wall in daily life; when the window films/windows are transparent, even if a family member is bedridden, they can be easily watched over and be quickly informed of the condition of the ailing member, and when a visitor arrives the window films/windows can be switched to opaque with a switch (Figure 9).

The LDK-integrated model case was selected for a detached house in Mawaoka City, Tochigi, Japan (Figure 11) [41]. The interior area of this case is about 74 square meters, and the bedroom is in the Japanese style. It was completed in 2019, and the facilities related to aging were retrofitted at a later stage. The bathroom, toilet, and other corner spaces are in accordance with the Japanese nursing home design standards. The cost of retrofitting, excluding equipment, was approximately 2 million JPY, accounting for 10.26% of the original construction cost of 19.5 million JPY. By installing smart devices such as inspection sensors at a later stage, it will be possible to respond quickly in the event of an emergency to ensure the safety of users. The cost of the devices is about 2 million JPY, and the cost of the network monitoring service is about 20,000 JPY/month. The total cost has increased by 20.51%.

With regard to the operability of the device, a device with at least two types of controls (smartphone controls, speaker controls, other controls) was selected (Table 3) so that the device can be used regardless of an individual’s lifestyle and physical ability.

From casebuilder user satisfaction surveys, residents felt that the open layout improved space utilization, reduced activity lines, made daily activities easier, reduced the risk of falls, and improved the operational efficiency of the caregivers [42]. In addition, the design promotes residents’ interaction with family and caregivers and reduces loneliness, making it particularly suitable for elderly people living alone or in small retirement apartments. The integration of smart home systems, such as smart lighting, health monitoring, and remote control devices, also further enhances the convenience and safety of living. Overall, the design model has a high degree of adaptability and acceptance in senior living facilities and can effectively improve the living experience and quality of life of the elderly.

The results of the design cases show that even though case costs increased by an average of 18.35%, the rational arrangement and diversified operation methods of smart devices can effectively compensate for the structural defects of different house models and improve the safety and convenience of living. For example, the smart sensors and camera devices in the LDK-integrated model enhance the ability to respond to emergencies, while the smart window design in the LDK-continuous house type improves the efficiency of space utilization and the convenience of care. Therefore, the smart solution of smart nursing homes not only optimizes the living experience of the elderly but also improves the efficiency of caregiving, providing a feasible solution for the promotion of the smart elderly model in the future.

7. Conclusions

This study focuses on the establishment of smart nursing home design guidelines in an aging society and proposes a systematic research framework, including smart device selection criteria, the development of smart nursing home model templates, and the application verification of design cases. In contrast to traditional approaches to nursing home design that focus primarily on basic accessibility and safety, this study innovatively incorporates smart technology as a core element to move from reactive care to proactive and technology-assisted aging solutions.

First of all, the study points out that the limitations of the current standards are mainly reflected in the following aspects: (1) failure to fully consider the diversified health conditions and personalized demands of the elderly, such as the different requirements of elderly people in different physical conditions for the living environment; (2) insufficient attention to smart devices, for example, the application of smart home, remote monitoring and health data monitoring technologies in improving the quality of life of the elderly is still in the preliminary exploration stage; (3) the standards focus more on hardware renovation and less on the design of soft environments, such as psychological needs and community support and social interaction, which is difficulty in fully meeting the comprehensive needs of the elderly in terms of physical and mental health. While previous studies have focused on tangible accessibility modifications, this study builds on this foundation by using social surveys as an entry point to both tangible (hardware) and intangible (social and psychological) aspects in order to create a truly supportive environment.

On this basis, the study clarifies the core requirements of the elderly for the living environment through a public awareness survey in Japan. By leveraging real-world user feedback, this study goes beyond theoretical assumptions and grounds its recommendations in practical needs. Based on the survey results, the study screens smart devices that align with the next-generation nursing home model and establishes selection criteria for smart devices, ensuring that the proposed solutions are both technologically feasible and user-oriented. At the same time, combining existing design standards and emerging requirements, the study develops a template for smart nursing home house types, optimizing spatial layout to improve nursing convenience and living comfort. Most previous studies have focused on either technological innovation or spatial planning. Studies focusing on technological innovation have proposed nursing devices and technologies that can be adapted to the elderly population and studies focusing on spatial planning have proposed spatial design scales suitable for the lives of the elderly. In contrast, this study combines these two dimensions to provide a holistic approach to smart nursing home design.

The study proposes guidelines for the design of smart nursing homes and verifies their feasibility and application through case studies. The results of the study show that the rational allocation of smart devices and optimization of the house layout can effectively improve the safety, convenience, and care efficiency of the elderly and make up for the shortcomings of the traditional nursing home design. In contrast to traditional designs that often prioritize security measures or cost-effectiveness, this study emphasizes the synergistic benefits of smart monitoring devices, accessibility design, and smart home systems to ensure a balanced and adaptive care environment.

The design guidelines proposed in this study provide comprehensive guidance for relevant designers and decision-makers to help them scientifically and reasonably select and configure smart devices and effectively apply them in the planning and construction of nursing homes. By clarifying the functional positioning and selection criteria and matching smart devices with actual use scenarios, the guidelines not only optimize the design of smart nursing homes but also improve the functionality and applicability of the facilities. Compared to existing frameworks that often lack detailed implementation strategies, this study provides practical decision-making tools to facilitate real-world adoption of smart nursing home concepts. Moreover, it bridges the gap between conceptual smart home designs and their practical execution, offering technical support and operational references for future smart nursing home development.

Overall, this study changes the traditional thinking of the construction industry in the construction of elderly facilities from a single barrier-free design model to a smart elderly environment with fully integrated smart technologies, promotes policy change, technological innovation, and industry synergy, provides theoretical support and practical reference for the large-scale promotion of smart elderly residences, and provides new ideas and technological support for coping with the global aging society. Future research can further explore the aging requirements of different countries and regions, optimize the matching strategy of smart devices, and combine more advanced data analysis and AI technologies in order to build a more complete and personalized smart nursing home system. For example, in smart nursing homes, machine learning can predict health trends, deep learning can enhance behavior recognition and health assessment through sensor data, and data mining can identify life patterns and care needs to support decision-making. These technologies enable more accurate, convenient, and efficient personalized care.