Passive Design Elements in the Architectural Planning of the Public Libraries : Focusing on the Comparison between Site and Building in the G-SEED Pre-certified and Non-certified library

1.1. Research Background and Purpose

Although sustainable architecture is demanded for all facilities, it, as well as its expansion, is more important for a public library because the public building plays a variety of roles as a community space for local residents such as providing cultural contents, supporting educational activities, offering space for leisure space. Furthermore, a modern library is asked to provide pleasant environment as well as a basic function of lending books. Here ‘pleasant environment and space’ means not only facility elements, which are provided artificially, but also one that is comfortable enough for people to use the library for a long time and that is offered in harmony with nature in real sense.¹⁾ It means passive design, which can provide pleasant environment and efficient energy by making the most of natural energy, should be most essentially considered at an early stage, so an sustainable library can be built. In this respect, the present study is aimed to identify the evaluation factors for the architectural planning elements of a public library in the perspective of passive design, apply the evaluation factors to cases to examine in this study, and examine how passive design affects G-SEED²⁾ Certification System and architectural planning elements of a public library. The findings of this study are expected to be basic data in planning an sustainable public library in future.

1.2. Method and Scope

The present study is conducted in the following orders. First of all, public library-related laws and planing standards are reviewed and then precedents studies are examined with care to define passive design. Based on the planning elements derived from the library planning guideline and passive design elements found in the literature review, the present study tries to classify the planning elements of a public library again from the perspective of passive design and uses them for case studies.

For cases to study, this study selected 6 libraries that acquired a preliminary certification by G-SEED and 6 libraries chosen as excellent architecture by Ministry of Culture, Sports and Tourism. The geographical scope of case study is limited to the libraries established in metropolitan areas. In addition, since it was hard to set temporal scope of study because Excellent Public Library Competition Project stopped after 2012, this study used the certified year of the libraries that acquired green architectural preliminary certification and opening year for ones chosen for excellent construction as criterion for case selection.

It is necessary to consider the elements of passive design overall to realize the efficiency of building performance. However, this study limited the selection and evaluation of the elements to those related to the usage of land on which a building is established and to those related to a building necessary to understand environmental friendliness.

2.1. Applicable Law and Guideline to Public Library

The laws related to building a public library can be divided into Libraries Act, Building Law, and ordinances related to Sustainable Law. According to Article 2 of Libraries Act [enacted Sept. 28, 2015], public library is defined as a library constructed for the main purpose of enhancing use of information and culture, activities of research, education and culture, and lifetime education for local residents. In article 2 of Building Law [enacted Oct. 7, 2015], library facility is categorized by size into the 1st class neighbourhood living facility with gross floor area of less than 1,000㎡ and education/research facility with gross floor area of more than 1,000㎡.

According to Article 15 of the ordinance of Act on the Promotion of the Development, Use and Distribution of New and Renewable Sources of Energy [enacted March 30, 2015], a building with gross area of more than 1,000㎡ is obliged to the compulsory ratio of new and renewable energy supply. In addition, Article 10 of the ordinance of Green Architecture Support Act [enacted May 29, 2015] stipulates that a building with gross area of more than 500㎡ shall submit an energy conservation plan. Article 13 of Regulations for G-SEED [enacted June 30, 2014] states that when a public building with gross area of more than 3,000㎡ is built or extended with an annex building, it shall acquire higher class of G-SEED preliminary certification and main certification than announced.

As mentioned above, institutional efforts are being made toward energy conservation and sustainable building and the coverage for obligation becomes more inclusive. Likewise, applicable laws and regulations also have greater impact on the architectural planning elements of sustainable public library. Not legally binding, library facility guidelines were also issued in consideration of the characteristics of a library (see Table 1). ‘Standards of Korean Libraries’ and ‘A Manual on Construction and Management for Public Libraries’ cover all kinds of libraries in Korea and other standards and guidelines regulate the criteria and operational models of public libraries.

Table 1.

Construction plan and guideline of pubic libraries

2.2. Increase of Social Demand of sustainable Public Library and Precedent Studies

‘The 2nd General Library Development Project (2014~2018)’ of The Library and Information Policy Council subject to presidential supervision is a comprehensive plan that proposes the promotion targets and task of all kinds of libraries. It puts forth the environmental change and countermeasures related to library. In the plan, ‘base expansion and operational stability for library’ and is decided as one of tasks to promote by strategy and ‘build 1,100 libraries until 2018’ is determined as policy agenda. In addition, the project plans to apply consultation service of experts in field of construction and operation even from the stage of construction in an effort to make the space and facility of a public library efficient. The government already announced that it would support the construction of 69 sustainable and energy efficient public libraries from 2008 to 2012. Like this, the demand for sustainable public libraries is ever increasing, but the standard for sustainable public library, which reflects the characteristics of library facility has been prepared yet.

According to the performance of G-SEED announced as of march 2015, in the homepage of The Ministry of Environment, The current status of G-SEED Certification for public library is as seen in Table 2. The table shows the annual number of public libraries by G-SEED Certification. It is stipulated by law that public facility with gross area of more than 3,000㎡ should acquire G-SEED Certification. Therefore, the number of the public libraries certifications will keep increasing.

Table 2.

The Status of G-SEED certified library

Of the studies regarding sustainable library, Korea Culture & Tourism Institute (2010) surveyed energy consumption of 60 cultural facilities and analyzed and calculated the carbon emissions of national cultural facilities.³⁾ Among those, it is difficult to reduce energy consumption of public libraries because they need to provide users with pleasant environment and rather need more energy to maintain constant temperature and humidity for book storages and computer server rooms. Furthermore, a public library is a facility where many and unspecified persons use, there is a limit to energy saving in terms of operation and management. In other words, since it is difficult to reduce energy load after a library facility opens, it is very important to seriously consider environment friendliness at the stage of design.

And when life cycle cost and energy consumption are considered, it is imperative to consider passive design from the stage of design to build a building with zero energy consumption.⁴⁾ However, studies related to sustainable library are not sufficient in Korea. Hong Su-ji (2014) conducted a survey on staffs in library to examine their awareness of establishment and current status of green library. Ahn In-ja and others (2) (2014) examined the academic trend of green library and proposed 5 areas to study in future. Ahn In-ja and others (3) (2012) defined green library and carried out case study with domestic libraries that acquired GBCC Certification and foreign libraries that acquired LEED Certification. Ham Mun-ju (2011) looked into low-carbon design techniques to materialize sustainable library construction and divided them into passive design and active design. And Ham studied Norman Foster’s works and derived the elements for low-carbon design techniques.

Like this, studies are not being actively conducted upon domestic sustainable library facility and operation. Therefore, it is now necessary to study the architectural planning elements of library facility so a library building can become environmentally friendly and its efficiency can be secured. Therefore, this study analyzed precedent studies and define passive design. It also discovered the elements of design and applied them to established public libraries (cases) to know the current status of the application of passive design to public libraries and its impact upon public library plan.

2.3. Passive Design in sustainable Architecture

Sustainable architecture is construction that saves energy and resources, preserve natural environment and improve human health and pleasantness.⁵⁾ Passive design is one of design techniques that enable sustainable architecture. This study reviewed precedent studies to define ‘passive design’, which is one of design technique, and the results are as follows in Table 3. From the precedent studies, definitions of passive design is characterized with understanding of relationship between land and climate, use of natural energy, reduction of power load, and provision of pleasant indoor environment. However, it was found that researchers have different opinions on the use of new and renewable energy.

Table 3.

Analysis of previous researches

This phenomenon seems to result from still being locked up in literal meaning and concept of ‘passive’ and ‘active’.⁶⁾ However sustainable architecture is possible when natural environment and strategic new and renewable energy are used in harmony. Therefore, the present study defines ‘passive design’ as follows.

Passive design is an architectural planning technique that maximizes the use of natural energy on the basis of the geographical features of building site. That is, it is “an sustainable design concept that provides users with pleasant space and environment by more using natural energy and less using fossil energy and a design method to consider even the performance of a building as well as the external functions of a building.” Therefore, discussion is made on the use of natural energy in terms of passive design to improve building performance. Because of this, passive design exerts a massive power at the stage of plan and design.

3.1. Facility Planning Guideline For Public Library

Passive design is characterized with using a site through the understanding of climate, architectural planning to take advantage of natural energy, and providing pleasant indoor environment by reducing power load. The elements of passive design are largely categorized into 4 areas: use of a site, architectural planning elements, indoor environment, and the use of new and renewable energy. However, this study divided the elements only into the use of a site and architectural building planning elements because the purpose of this study is to examine the impact of passive design at the stage of design. For the use of a site, such elements are included in passive design as layout and direction, preservation of original site, and elements related to mass form. And architectural planning elements include those related to space planning, ventilation, lighting, and indoor green.

Table 4 summarized the detailed standards and guidelines of 5 architectural planning elements of a public library from the viewpoint of the use of a site and architectural planning elements. The introduction of ①Standards of Korean Libraries(2013) explains that ‘it is a measure legislated to achieve the quantity, quality, coverage, and level set by special body or a governmental department that supervises libraries and evaluate the progress. It stipulates the identity of a library and presents data and indexes for library facilities by type, which are not designated in law’. Like this, Standards of Korean Libraries is the important basic data for library policy, plan and facility construction by type. ②A Manual on Construction and Management for Public Libraries(2013) is issued by the Ministry of Culture, Sports and Tourism. It says that it is aimed to provide a guideline to ‘administrative procedure for the construction and remodeling of a public library, and construction guideline and space composition.’ It provides specific and detailed architectural planning elements such as setting construction concept, space size planning, remodeling plan, and environmental facility plan. ③Guideline of the Public Library Operating Standards(2012) is published by Seoul City Government. It is aimed to set standardized work guideline for public library. ④A Study on Development of Operation Model For Gyeonggi-Do Public Libraries(2013) is a study aiming to provide a standard model for operation, construction and cooperation system of a public library. In that study, construction size, necessary space, and sustainable layout plan. Last, ⑤A Study on the Present Status of Korean Public Library Space Management and Standard Model (2007) is a study policy proposal and standard model development necessary to be considered in constructing a new library.

Table 4.

Detailed contents based on the standards and guidelines of public library

Reviewing these planning guidelines allowed us to confirm that site has elements of location (area for population), accessibility of public transportation within in certain radius, and identifiability such as night lighting and installation of a sign. And a building has such elements as efficiency that fix walls, columns and partition walls are less used to secure smooth walking line, scalability for securing external space and variable space and functionality for preparing rooms for related facility.

3.2. Passive Design Elements

5 precedent studies were reviewed to derive passive design elements for the use of a site and architectural planning elements. ①Kim byul (2013) extracted natural ecological elements and examined precedent studies and cases later. And the researcher added material and new and renewable energy section and derived passive design elements. ②Koh Gwi-Han (2015) chose 5 items such as climate characteristic, geographical features and layout, formative structure, plane composition, external skin plan and material composition, and illustrated relationship among 5 items. ③Kim Chul and others (2) (2013) analyzed related systems and cases to provide a guideline to passive design and included plan elements and technical elements. ④Yim Su-Hyun and other(1) (2010) divided passive/ active design depending on natural environment element and listed them. And they checked the application status of the list to domestic and foreign cases. ⑤Lee Bong(2011) explained passive design technique and elements as sustainable architecture design.

Table 5 shows the list of passive design elements found from each of those precedent studies. The present study selected the elements with most frequency and analyzed association with library architectural planning elements. And they were chosen as evaluation factors.

Table 5.

Evaluation elements of passive design from previous researches

3.3. Planning Elements of Public Library from the Perspective of Passive Design

Earlier, the common elements of architectural planning elements of a public library and passive design were derived. These common elements were re-classified by calculation method and installation. And the final planning elements of a public library from the perspective of passive design were prepared as seen in Table 6.

Table 6.

Evaluation criteria of sustainable public library in the aspect of passive design

For the use of land at the section of site, biotope planning is evaluated to know if ecological environmental area can be secured, and eco-parking space and facility is evaluated for ecological green-network in outside space. For layout and direction, the relationship between road width (one or two lanes) and accessibility is evaluated for accessibility of library for external users. In addition, optimum angles of main direction (southward) of a building are evaluated for daylight performance, which heavily affects cooling and heating efficiency.

In the section of building, buildings are divided by form. the energy requirement distribution by W/D ratio shows that annual load more reduces as building is more square even for the same volume.⁷⁾ Therefore, A/V ratio and aspect ratio, which are the indexes of library shape, are important in architecture design. A/V ratio is the ratio of surface area to volume on the building energy performance. To calculate A/V ratio, this study referred to a building register and multiplied floor area of each floor by hight for volume. External skin area was calculated in 3D model using Sketch Up, which is a modeling program. And the external skin area was divided by the volume and converted into percentage to get A/V ratio. Aspect ratio (W/D Ratio) is calculated in percentage of the width of a building to its depth, which can be obtained in a layout plan. Besides, one point was assigned to louver, shading devices, light well, light duct, and atrium, if there is, to evaluate the natural lighting and natural ventilation of a library. And two points were assigned when two elements wete installed or formed: biotope of land and aqua plant, green rooftop and green indoor, louver and shading device, and light well and light duct. And the highest point 32 was given to the case where these elements were all installed and land environment and architectural planning elements were all applied, say, when a building is laid out southward, close to share shape, and of simple mass.

4.1. Cases of Public Library and Characteristics of sustainable Planning

G case group consists of public libraries that acquired more than preliminary certification according to G-SEED Certification system from 2011 to 2014, while N case group consists of public libraries without green certification but chosen as excellent public library by the Ministry of Culture and Sports in 2012. This study applied the evaluation index to 6 cases and analyzed them. Table 7 shows the results.

Table 7.

Case study of sustainable public library

G1 is located within Ilwol Park and has land plant biotope. Inside, light well and horizontal green are installed as well as louver. G2 uses double external skin and horizontal green facilities such as green indoor and green rooftop are installed inside of each floor. Light well is also introduced inside. G3 had a kindergarten on the first floor and a rooftop garden as well as an open deck on each floor. Other passive design elements are not installed. G4 has a family center within the same site, but the buildings exists as separate unit. A/V ratio is only considered for the library unit. Insides, a courtyard is arranged for natural ventilation and louver is installed. G5 has louver and acquired main certification in 2014. G6 planned and installed a garden on every floor from the 2nd floor to the top (vertical green) and acquired main certification in 2013.

N1 is located in Bora Park and has louver at the facade. N2 has a courtyard and a light well together inside and has louver at the facade. On the top, solar energy generator is installed. N3 is located within Kyoha Jungang Park and has rooftop garden. The atrium installed inside is connected to the library to right to left. N4 has a sports center in the same complex. The library unit and the sports center unit are separated on the level but they are connected by a underground swimming pool. A/V ratio of individual building on the library unit were reviewed. N5 is located near Hongryung Neighborhood Park and has natural experience activity workshop on the rooftop. N6 is located within Onsu Neighborhood Park and light well, rooftop garden, and louver are installed.

Each case was scored according to the evaluation criteria for architectural planning elements of a public library from the perspective of passive design and the results are shown in Table 7. The angles of main axis of a building were calculated with directions described in a layout plan. For the calculation of A/V ratio, basically, mass on the ground was calculated. And only for a building whose external wall of basement floor is exposed over the ground so underground can be accessed from the ground, mass was calculated by adding external wall area. Aspect ratio (W/D Ratio) was calculated with the length of long side of a building as described in the layout, which was divided by the length of short side. As for horizontal green, of which installation needs confirmation, it was divided into rooftop garden and green indoor installed inside a building. For vertical green, only when a garden was introduced at the facade of a building, it was accepted. And louver, shading device, atrium, light shelf, light well, and light duct were checked for installation.

4.2. Case Analysis and Comparison

The total evaluation scores of the certified and uncertified libraries under G-SEED Certification System turned out to be 86 and 72, respectively, and the score of the certified libraries was 14 points higher than the uncertified ones on average. G1 has the largest passive design elements and the score of G3 was lower than the average of the uncertified libraries. In addition, while the uncertified libraries did not have scores both in land and aqua plant biotope, the scores of 2 uncertified libraries were higher than the average.

Of the elements of passive design, the certified libraries had 23 scores from the passive design elements related to land and building such as biotope, louver, shading device, and atrium while the uncertified libraries earned 13 from them, so there was obvious difference. It is because the libraries gained scores (from the items such as biotope and horizontal green) in the process of acquiring preliminary certification. That is, all the cases with preliminary certification installed green rooftop and 4 of them installed green indoor. Furthermore, Biotope was found only in the certified libraries. The second most installation among passive design elements was light well. G1, G2, N2, and N6 were found having a light well of void slabs that were inserted in the lower floors, including the ground floor, from the ceiling. G6 and N3 had a light well on the ground floor so as to light the basement parking lot. Besides, louver was found installed in 5 libraries of the total. Vertical green was found in 2 libraries. For atrium, only one uncertified library had it.

As for 3 evaluation items that require mathematical work to assess such as the angles of the main axis of a building, A/V ratio and W/D ratio, the difference in the total score between the certified and the uncertified libraries was minor (by 2). The entire cases were similar in the score of A/V ratio and rather the score of the uncertified libraries was relatively higher. It is because that most of the libraries are built in a single unit building in a complex and they have similar plane structure both in low-level and high-level floors. Furthermore, it was found that their rooms are layered vertically. The total score of building layout was turned out similar for both groups. For W/D ratio, there was 3 point difference between two groups and the score of the certified building group was higher.

As a result, the total and average score of the certified libraries were higher than those of the uncertified libraries. The gap in the scores stemmed from the installable elements related to land and building (e.g. biotope, louver and shading device). In other words, although two groups showed similar scores in building layout method, direction and vertical expansion in land environment, the certified group accepted passive design elements more actively.

4.3. Relationship Between Evaluation Items of G-SEED Certification System for Public Library and Passive Design

G-SEED Certification System is a tool to certify architecture of its environmental friendliness by saving energy and reducing environmental pollution in the whole process of construction. Judging from the results of this study that conducted the evaluation of passive design adopted by the certified public library, the certified libraries have slightly better than the uncertified libraries. Therefore, this study was impelled to analyze the relationship between G-SEED Certification Standard and passive design elements. G-SEED has 10 standards by building type: apartment housing, complex building for residential purpose, complex building for office, school, business, accommodation (lodging), small residential housing, existing apartment housing, and existing office facility and others. Public library is subject to the standard for ‘others’. Therefore, this study carried out a correlation analysis between G-SEED Certification Standard for ‘Other Buildings’, which was revised on June, and passive the elements of design for the public library. The results are as in Table 8.

Table 8.

Analysis to correlation between sustainable public library & G-SEED

As in the results of the case study of public library of Table 7, it turned out that the certified libraries accepted passive design actively to realize sustainable public library. However, as Table 8 confirms, the evaluation items of G-SEED Certification System for passive design elements are sufficient. Therefore, to the certified libraries, introduction of passive design elements is not a tool to acquire certification, but purely use them as sustainable architectural planning elements. That is, passive design elements recommended in G-SEED Certification System should be realistic and plausible so that those passive design elements can be used as architectural planning elements.

Although the standards currently used under G-SEED Certification System include land/aqua plant biotope, indoor water space, planting space, green rooftop, wall green and also have evaluation tools, they have no standards for direct architectural planning elements such as building mass form, layout method, and day light regulating device. Library facility uses such passive design elements as horizontal green and louver most frequently, but G-SEED Certification System does not have such criteria to evaluate. Therefore, it is necessary that the system be more specific and realistic to realize the elements of sustainable architecture of public library by considering the relationship between such elements and energy efficiency and conservation, not only as a tool for institutional certification.