A protestant church stands at a rich green residential area which is 10-minutes away from Shonan beach on foot. The chapel of the 50-year old church became too small and it was therefore decided that a new church would be constructed on a different site. Church authorities said that the passages of the Bible are read and heard in service. Therefore, "We wish to have a chapel appropriate to give praise to the Lord.
*Six roofs The architectural design was a one-storied building with a restrained height so that it could harmonize in a low-rise residential area. It was aimed at creating a space appropriate to prayer and worship with the six curved surfaced roofs at different heights. This allows natural light to pour down from the ceiling. It conveys the message that six roofs represent the six days of Creation in the Bible genesis and Mass celebrates the seventh day.
Direct sunlight and indirect light are regulated depending on the time of the day. At the time of service there was no direct exposure to sunlight, whereas the rest of the time there was. Therefore, this construction was designed to receive an appropriate amount of indirect light during service time. So, light was simulated using computer software at intervals of 30 minutes on the designed days during 12 months and manipulated depending on the time of the day. There would be a space under a soft light at the time of service throughout the year. Towards the end of the service, direct sunlight begins to draw a ray of light on the wall surface. In the afternoon there is only one line of direct sunlight, and around 3 o’clock light comes in like a shower, creating a dynamic environment.
* (Stiffening) Ribs of sound and light Uneven longitudinal ribs were carved at a random rhythm on the exposed RC concrete wall of the chapel, and dark gray acoustic boards were placed between the ribs. A solution to the requirement was reached by achieving balance. This was possible using concave acoustic boards to make it easier to hear the priest’s sermon and Bible Readings, and improved the sound of ecclesiastical music such as hymns with RC convex surfaces. Flutter echo was reduced by rib pitches placed at random. A light grey light shines directly on the convex surface stands out due to its contrast with the dark grey concave surface. Based on the idea that modern church construction has to provide a space that facilitates the Bible Readings, it came to our minds we should achieve direct sunlight shining through a dark space.
*Direct moonlight Under the sky of Shonan, we can participate in a service, read and hear the words of the Bible and have the opportunity to pray in a space under dynamic direct sun light in the afternoon. Direct moonlight shines through the pitch-black chapel at night during full moon. We hope the conception of time and space will harmonize with the local nature and scenery and people will gradually come to love the construction.
*Outdoor terra-cotta cross Reverend Furuya picked up 5KG of sand with his own hands in the premises of the previous church and used it to make a terra-cotta cross. This is because he wanted to emphasize the 50 years of the Christian church of Shonan and desires of the congregation.
*Open rainwater gutter Slits were made on the outside wall at the lowest point of circular arcs to create open rain gutter. As a result, it could be enjoyable to see rain flow through the gutters, and despite the abundance of pine leaves, these do not block the gutters.
*Direct sunlight and prayer Direct sunlight alters the space in the church in different ways creating the perfect environment for player. After the service, it becomes a space for a prayer for a small number of people and one to two or three rays of sunlight shine throughout afternoon.
*Indirect light and service The passages of the Bible are read, and heard in Mass. It is inappropriate for the Bible and people to be exposed to direct sunlight during service. Indirect light is appropriate for service. The space was designed to receive indirect light during services from 10:30 a.m. to 12:00 a.m.
*Chapel afternoon Only one thin ray of direct sunlight shines through the chapel when the hymn is sung towards the end of service
*The Creation relief tiles Relief tiles about the creation showing motifs of the hand of God during the six-day Genesis were introduced in the north-south walls under the six roofs. Unbaked tiles were engraved with original pictures from the Genesis and baked one by one. The color of the tiles is a semi-transparent light blue inspired by the morning haze. The pictures of the six days were slightly different in design depending on orientation. Finding pictures not only in the chapel but also in various rooms including the rest room, kid’s room, and pastor’s room added to the enjoyment.
From Arup: The curved as-cast concrete roof is a one of the striking feature of the Church, in the quiet neighbourhood, located in Shonan area where is along the coast of Sagami Bay in Kanagawa, Japan. This church provides approximately 175m2 and has single storey with RC structure. Arup was consulted about structure and lighting environment .
Associate with the hexameron in the Creation of Genesis, the architect, Hosaka Takeshi was inspired and designed the “six” roofs. The characteristic 6 curved slab is designed not only architectural reason but also it provides structural, acoustic, and lighting benefits. By steric effect from their curvature, the roof can span 7.6m length only with 250mm thickness and in each curved slabs, there’re void tube which reduces the weight of the structure. In the case of the seismic, especially their spanning direction, the shear wall with 300mm thickness and the curved slabs behaves as if moment frame structure since the girder slab has stiffness for the direction. The both side of each roof, there’re gaps in order to taken in natural sunlight. They brighten the space of chapel with daylighting and it secures sufficient supply of illuminance. Therefore, the daylight from the opening is enough to be able to fill the space with bright natural light during the daytime. The opening is also designed to avoid the direct sunlight during the time of worship. The curves provide us to avoid intensive the sound of carol and sermons. Having curvature, the sunlight reflects spreads into the room and it is blighter than the case of flat slab. Even the moonlight falls to the inside and leads us to fantastic world.
From Nagata Acoustics: Among the acoustical design requirements for the sanctuary, a focus was made on ensuring that the congregation would be able to hear the sermons clearly. To this end, the reverberation of the space was limited to an appropriate level and measures were taken to inhibit the occurrence of undesirable echoes. Architecturally, the sanctuary’s ceiling was planned to be the exposed underside of the building’s curved concrete roof. From an acoustical design perspective, this curved shape provides abundant early sound reflections to the sanctuary uniformly. On the other hand, since the side walls of the sanctuary were designed to be parallel, smooth concrete surfaces could result in undesirable echoes. Furthermore, we needed to add sound absorbing material to the side walls to avoid excessive reverberation. For both of these, a pattern of vertical ribs with a random periodicity was created on the concrete side walls. And between the ribs, strips of sound absorbing black urethane foam were inserted. In the sanctuary, the pastor's speech could be heard clearly and easily throughout the space, while the hymns could be heard softly.
ARCHITECT TAKESHI HOSAKA STRUCTURAL ENGINEERS HITOSHI YONAMINE / OVE ARUP & PARTNERS JAPAN Ltd ACOUCTICS AYAKO HAKOZAKI / NAGATA ACOUCTICS PHOTOGRAPHER KOJI FUJII / Nacasa&Pertners Inc. CLIENT SHONAN CHRIST CHURCH
QUESTIONARY TO PRODUCT INQUIRY Name of the project SHONAN CHRIST CHURCH Exact definition of the building church Location of the project Kanagawa , JAPAN