jørn
utzon logbook
vol.II
Thank You for Light Thank You for Life T h a n k Y o u f o r All Y o u h a v e g i v e n
bagsvÆrd church
jØrn utzon / torsten blØndal
edt. blØndal 2005
C ON T EN T S
SERIES OF DE T AI L S B Y RI C HARD W ES T ON M A T ERIA L S 3
ZODIA C SERIES . S Y DNE Y O P ERA HOUSE M INOR HA L L B Y J Ø RN U T ZON GEO M E T R Y 1 4
C HRIS T IANI & NIE L SEN SERIES B Y GOD T FRED JENSEN BUI L DING SI T E 3 8
J Ø RN U T ZON SERIES SKE T C HES 5 3
SUI T E OF P HO T OGRA P HS B Y O L E M E Y ER E T C . IN T ERIOR 6 0
SUI T E OF P HO T OGRA P HS B Y O L E M E Y ER E T C . e x T ERIOR 9 0
AR C HI T E C T IN T ERVIE W 1 1 4 S P EE C H A T C ONSE C RA T ION 1 1 9 DRA W INGS 1 2 0
ASSIS T AN T AR C HI T E C T C O M M EN T S 1 3 6
BUI L DER P ROGRA M M E 1 3 9 T HE P ROJE C T 1 4 0 A L T AR 1 4 1
ENGINEER DES C RI P T ION 1 4 2
ORGAN DES C RI P T ION 1 4 4
W OOD W ORK DES C RI P T ION 1 4 5
T EX T I L ES FA C SI M I L E L E T T ER 1 4 6 P RO C ESS , P HO T O SERIES 1 4 8 SA C RIS T Y 1 5 0
ANA L Y SES A C OUS T I C S 1 5 2 BUI L DING S Y S T Em 1 5 6 L IGH T 1 6 0
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T h e Ac o u s t i c s
“ It i s t h e l i g h t t h a t i s t h e m o s t
in Bagsværd Church
i mp o r t a n t t h i n g i n t h i s c h u r c h . ”
Bo Mortensen civil engineer, associate Professor
By h a n g i n g a plyw o o d r e f l e ct o r a b o v e t h e a mp h i t h e a t r e a n d s u s p e n d i n g i t f r o m t h e c o n c r e t e s h e ll r i b s , w e h a d c o mpl e t e f r e e d o m i n s h a p i n g t h e r e f l e ct o r a n d c o u l d f o ll o w t h e acoustical needs. Many shapes were tried out. The final form gives a very fine acoustical performance. Z o d i a c 1 0 , M i n o r H a ll SOH , J . U .
Jørn Utzon’s words are not, however, a sign that the acoustics were accorded a lower priority in connection with the design of Bagsværd Church. On the other hand, the church’s natural acoustics appear to have been created as the result of logical considerations of the geometry and the materials, so that they are experienced in a harmonious relationship with the church’s lighting and visual qualities. Nowhere do we build so consistently on an aural tradition as in a church, and from no other type of hall do we have such clear memories of acoustic conditions and experiences. When the organ, the choir and the bells fill the church with sound, our experience, to an even greater extent than in a concert hall, is a combination of the source of the sound and the special acoustic character of the place. We are then in an acoustic space which in itself is an instrument, and when correctly proportioned can be used for speaking, intoning, singing and making music. To live up to the desire for the ease of understanding natural speech in a space that is also to be the setting for church music and related experiences is as good as impossible. The acoustic damping that would meet the desire to be able to hear the clergyman’s words clearly would destroy the sound qualities required for showing off the organ and choir. Conversely, a reverberation such as an organist and choir find optimal would lead to great difficulty in understanding the spoken word, especially at the rear of the church. Bagsværd Church is one of the finest solutions available for the complicated and, in principle, irreconcilable acoustic requirements that have to be incorporated into a modern church. Jørn Utzon has created a church in which organ music and choral singing sound simply wonderful, but at the same time is designed so that natural speech is optimised insofar as is humanly possible. And this is done in such a simple, natural and overriding manner that the devices can be read directly out of the main geometry of the church. On the one hand, the body of the church is shaped in such a way that the congregation is placed as
close as possible to the altar and pulpit, and on the other the “cloud” above the rear of the church is designed as a transverse sound reflector that deflects the sound down towards the pews that are situated furthest away from the preacher. In this way, the clarity and intensity of his words are increased and so the ability to understand his words is optimised. Thus, in an acoustic sense, the line of the undulating ceiling extending between the parallel walls is both exemplary and logical. In the part of the church where the ceiling is highest, where the concrete wave forms vaulting, a space has been created for the organ, not only in a physical sense, but also with regard to sound, in that the greater volume results in the longer-lasting reverberation that the organ and choir require, and which our church tradition determines. The simplicity and logic in the shaping of the ceiling can be seen, for instance, as an off-shoot of the intensive work on designing the optimal geometry for the ceilings in the Sydney Opera House auditoriums, which Jørgen Utzon along with the acousticians Lothar Cremer and Werner Gabler had worked towards during the period 1962-66. During this process, the original concave ceiling profiles in the auditoriums had evolved into convex, cylindrical segments with a view to avoiding focusing the sound and to achieving a better distribution for the audience. Over the pews in Bagsværd Church there is the same need to avoid focusing and to distribute the sound reflections, and so the undulations that otherwise permeate the entire church are here replaced with purely convex ceiling segments. The church has a reverberation time of slightly less than 3 seconds. As a result, it is very resonant in relation to its size of only about 3,000 cubic metres, and consequently the acoustics promote the experience of a light, clean and holy place. The reverberation is a product of the material character of the building. The concrete surfaces used for the ceilings, walls and floor provide scarcely any sound absorption. The soft cloud shapes of the ceiling are thus in an acoustic sense quite hard and effective as sound reflectors. Lin Utzon’s textiles and carpets limit the medium and high frequency range, while the glass and the wooden pews in the
> An analogy for the spread of sound and the r e f l e ct i o n o f s o u n d i n t h e c o n v e x a n d c o n cave shapes in the church. The convex shapes spread the sound, while the concave ones c o ll e ct o r f o c u s i t .
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the breakfast parlor dome in Sir John Soane’S h0use in Lincoln Inn’s Fields, london. 1804