Dombauhütte Cologne
The Cologne Dombauhütte is continuously renovating the Cologne Cathedral with around 100 craftsmen, thereby maintaining the building; it thus continues the tradition of the medieval cathedral construction hut . It is made of Dombaumeister passed and today as part of Dombauverwaltung the Metropolitan Cathedral Chapter assumed. The hut, which was originally founded in the middle of the 13th century to build the cathedral, was one of the most respected Gothic construction huts in Europe in the Middle Ages. Today the Cologne Dombauhütte is the largest in Germany and one of the largest in Europe.
History of the Dombauhütte
The medieval history of the Cologne cathedral building works must essentially be derived from archaeological sources and building research. In 1794, the French revolutionary troops dissolved the building works and removed all written documents that have since disappeared. Only a few plans - such as the facade plan F from 1370 - could be found again in the 19th century.
Quality standard of the Bauhütte
The cathedral construction hut was set up in 1248 by the first cathedral master builder Gerhard . Stonemasons who had gathered their experience building the numerous Romanesque churches in the Cologne area were probably gathered for this purpose . In any case, the Kölner Hütte continued the Romanesque construction methods with the construction of the Gothic cathedral and did not fall back on the more modern experience of the northern French huts.
The Kölner Hütte developed a high quality standard in the first 100 years. The crack F of the west facade, designed by master builder Michael von Savoyen in 1370, shows, for example, an “extraordinary graphic quality” and a level of detail based on a long tradition of Gothic plan drawings. He is therefore “without a doubt one of the greatest architectural drawings left by the Middle Ages”.
Organization of the construction hut
In the Middle Ages, the construction hut consisted of around 100 people. It belonged to the large companies at a time when the typical company organization was geared towards the craftsman's workshop. The cathedral builders (magister operis), who had to organize this large-scale business as a free association of stonemasons, carpenters and blacksmiths, were therefore considered to be the top earners in the craft. To do this, they worked closely with the building director (rector fabricae), a clergyman who coordinated the building work for the church builder and was also responsible for managing the finances. Today we can assume that the cathedral master builder had one or two master servants, the so-called parliaments, at his side. Together they organized the craftsmen for the rising masonry and those who worked on the foundations.
2 to 4 sculptors, 20 to 24 stonemasons and 6 to 8 relocators were probably working on the rising masonry. In addition, 3 to 5 carpenters will have worked on the construction site. 10 to 15 foundation masons worked for the foundations. The building works will have around 4 to 7 apprentices. Then there were the craftsmen who dealt with the expansion such as u. a. Painter, gilder and glazier.
The construction hut was also responsible for procuring the building materials. In the trachyte quarry on the Drachenfels, around 3 to 4 stone breakers and 3 rough bossers will have worked. In the basalt quarry, 4 to 6 stone crushers will have broken the foundation blocks. To organize the transport, three to four ships were used to bring the 40 to 50 stones with a volume of around 9.7 cubic meters from the quarry in Drachenfels to Cologne every day. 2 to 4 shipmen and 3 to 4 transport employees will have been employed for this purpose. Another 3 to 8 shipmen and 4 to 5 transport workers will have been required to transport the basalt.
In order to maintain the construction site, the cathedral chapter had to raise the necessary funds. According to the financing deed of April 13, 1248, all gifts that were placed outside the mass on the Petrus altar should be used for the construction of the cathedral. In addition, collections and donations were collected that were linked to a promise of indulgence. For example, Archbishop Wigbold von Holte (1297–1304) awarded a 14-day indulgence to all those who considered the cathedral treasury in their wills. Over the years it became customary in Cologne to donate at least one silver groschen to the cathedral from each estate. In the early 14th century the financing was put on a more secure basis when the Petrusbruderschaft was formed with the aim of promoting the construction of the cathedral.
Reputation of the Cologne building works
The reputation of the Cologne building works can also be seen from the fact that several well-known Cologne foremen have been appointed master builders for large building projects. The older Heinrich Parler had moved away from Cologne to build the east choir of the Augsburg Cathedral , which in its original conception was planned as a replica of the Cologne choir. Peter Parler moved from Cologne, where he presumably delivered his masterpiece, in 1356 as master builder for St. Vitus Cathedral in Prague . His nephew, the younger Heinrich Parler, worked at the Cologne Dombauhütte until 1378 and traveled from Cologne to Ulm in 1387 to take on the position of master builder . The foreman for the Milan Cathedral was also sought in 1391 in Cologne. In 1419 Johannes Hältz , who had at least assumed the role of a Palier in Cologne, was called to Strasbourg and built a tracery helmet there, which was clearly based on the Cologne planning (which was not yet implemented at the time). At the Regensburg Hut Day in 1459, the Cologne cathedral builder Konrad Kuyn was confirmed that the hut dominated north-west Germany. The builder himself was appointed to the Milan Cathedral during these years. The Regensburg cathedral builder Andreas Engel and his brother Hans had also learned in the Cologne building works. From 1442, Master Johannes von Köln had the opportunity to erect tracery helmets at the cathedral of Burgos , for which the plans in Cologne (which were still not implemented at the time) served as a model.
The construction works continued even after the construction of the cathedral was stopped around 1560 in order to carry out ongoing repairs to the building. Not until 1794 did it disband due to the French invasion; In the decades that followed, the building suffered major damage.
Bauhütte in Prussian times
In order to prevent the church from deteriorating further, Friedrich Adolf Ahlert re-established the building works as a Prussian state enterprise in 1823, which, however, followed the tradition of medieval building trade. Ahlert secured the substance of the cathedral choir and renewed four buttresses, the execution of which, however, was criticized as less successful.
During the completion of the cathedral from 1842 to 1880, the hut was significantly enlarged under the direction of the cathedral builders Ernst Friedrich Zwirner and Richard Voigtel . The number of employees was initially 180 and then even more than 500 craftsmen. Above all, master builder Voigtel also used modern production methods to speed up the construction of the cathedral and, for example, bought a steam engine in 1869 to lift the finished stones onto the towers.
After 1880, the construction hut was initially reduced to a small repair team. But when an angel figure fell from the cathedral in 1906, the need to carry out continuous restoration was recognized, and cathedral builder Bernhard Hertel increased the workforce of the building works to 70 by 1926. The hut has been under the cathedral chapter since 1948 .
Creative preservation of monuments
After the damage caused by the Second World War , Cologne Cathedral was restored by master builder Willy Weyres according to the principles of creative monument preservation . This term was coined in 1929. After that, the monument should not only be preserved, but also made understandable as a whole - and even changed for the better in the process. For example, Weyres (cathedral master builder 1944 to 1972) gave stonemasons a great deal of freedom to create free-form sculptures according to their own designs within the original outlines. Around 1980, cathedral builder Arnold Wolff ended this phase of design innovations and demanded that the existing neo-Gothic forms and not just those of the Middle Ages be copied as faithfully as possible.
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However, the cathedral owes a large number of original pictorial inventions to the creative freedom between the 1950s and 1970s. The ornamental figures of the north portal in the west facade, which was particularly badly damaged in the Second World War, also known as the Three Kings portal, has been restored in a modern form. The four outer figures depicting Abel, Jafet, Job and the Queen of Sheba, as well as the heads of the other most important figures (figures of the Old Covenant and the Three Wise Men) were recreated by Elisabeth Baumeister-Bühler between 1958 and 1960. The angels on the Wimperg were designed by Klaus Iserlohn and Erlefried Hoppe between 1956 and 1958. The sculptors Ewald Bell and Gerhard Stoll invented musical angels on a southern buttress of the nave in 1954, where in the original only foliage adorned the arch of the window.
In other places, figures from contemporary history and people with the facial features of the hut workers were carved in stone. An arch of the buttress is not adorned with crabs (creeping flowers), as it was in the Middle Ages , but rather small figures that represent the workers of the construction hut. Football players, boxers, a radio marie, US President John F. Kennedy, France’s President Charles de Gaulle and Soviet President Nikita Khrushchev have found their place at the cathedral. In the meantime, several billy goats , the mascot of the soccer club 1. FC Köln , adorn the cathedral. The first was created in 1962 by sculptor Werner Meurer as a gargoyle after Cologne had become German football champions for the first time.
Since the 1980s, stonemasons have only taken liberties where there are no more originals. They faced this creative challenge, for example, from 2004 to 2005, when the Cologne cathedral bomb, which was temporarily inserted due to severe damage during the World War , was to be clad with ashlar again. For 35 capitals, Markus Schroer invented new leaf shapes in the proportions of the lost originals and immortalized a. a. Clover, thistle, bougainvillea and black-eyed Susanne in the stone.
It is thanks to the same imaginative creative freedom that there is also a small figurine of Pope Francis on the cathedral . In the tympanum of the main portal a canopy had to be completely redone and included the figure was to draw a decorative gargoyle new. The stonemasons of the construction hut gave her the facial features of the Pope and added her arm and hand in what appeared to be a blessing gesture.
In addition, it has remained a beautiful custom to immortalize people from the cathedral building on the building. That is why the figures of the cathedral builders Arnold Wolff and Barbara Schock-Werner as well as the cathedral provost Norbert Feldhoff look out from the cathedral in suitable places . A figure of the provost Gerd Bachner , who retired in April 2020, will be immortalized on the north lattice of the cathedral. She wears a helmet to remember that Bachner climbed the finial of the north tower in 2015.
Ongoing restorations
The construction projects on the cathedral often take many years to complete. The cost of an individual construction site is often difficult to estimate because the construction project often appears small compared to the size of the cathedral. For example, in 2004 and 2005, the provisional brick filling of the Cologne Domplombe was replaced by stone. “Just replacing the cathedral cathedral was equivalent to building a village church in terms of workload.” Today, restoration is carried out with the claim that it will not require any further renovation for the next 200 years.
Brick 1943-2004
Stone since 2005
World cycle in the upper storey
Since 2003, the 16 upper clad windows in the transept have been restored and partly completely reconstructed from the original cardboard boxes. These windows were designed by Michael Welter around 1866 and are therefore named after the artist Welter cycle . The medieval king's windows in the high choir served as a model. In World War II, the windows were largely destroyed. The restoration of a window takes around two to three years, as not only must the panes be restored, but the stone work to which the windows are attached must also be restored. In 2005, the Salomon window, donated by the von Oppenheim family, was the first window in the cycle to be used again in a completely reconstructed form. In January 2020 the Zentral-Dombau-Verein zu Köln found a sponsor for the last window; the sponsorship per window costs 250,000 euros. Cathedral builder Peter Füssenich expects that all windows will be restored by 2035.
North tower pillar
The pillars of the two west towers are particularly exposed to the weather at heights of 75 to 100 meters. Therefore, in 1996, an extensive renovation project was started and the first of the hanging scaffolding, visible from afar, was hung on the top of the north tower. Above all, the Dombauhütte had to replace the old, corroded iron dowels, the rust of which threatened to burst the stones. At the same time, the approximately 2.80 meter tall and each 1500 kg heavy music-making angels that adorn the pillars had to be replaced. The arms, hands, wings and instruments of the figures designed by Peter Fuchs in 1876 were badly damaged by weathering . Two of them were accepted in 2015; they are now made up of two blocks of Savonnières - limestone newly manufactured completely and been flown in May 2020 back to the tower up. Cathedral builder Peter Füssenich expects that the renovation of the north-west corner of the north tower will be completed this year and that the suspended scaffolding will be dismantled by 2021. The work on the northeast corner of the north tower will then continue.
Buttress
The exterior buttresses are indispensable for the stability of the high-rise Gothic nave . It is used to derive the vault thrust and the wind load and therefore has an essential static task. Since the buttress is exposed to the weather on all sides, it is also particularly stressed by wind and weather. The Bauhütte has therefore been working on renewing this statically sensitive construction for almost 200 years. As early as 1823 when the building was refurbished, the work on the buttress of the choir was one of the first restoration measures under the direction of master builder Friedrich Adolf Ahlert . About 100 years later, cathedral builder Bernhard Hertel began a fundamental renovation of the choir buttress with stones made of shell limestone, which was continued by his successor Hans Güldenpfennig until the late 1930s . After the Second World War it turned out that the Schlaitdorf sandstone, from which the buttress of the transepts and the nave had been built in the 1860s, tends to weather heavily. In addition, many struts had been damaged by the war. Therefore, the buttress on the north transept was largely replaced by Lohndorfer basalt lava in the post-war decades. Although this stone is considered to be very durable, its greyish color differs from the original sandstone. The buttresses on the south transept were restored for around 30 years until summer 2015. The Bauhütte tried to preserve as much of the original structure as possible. Necessary additions were made with sandstone from Bozanov , which is very similar to the original stone . In the meantime the southern buttresses on the nave are being repaired.
Michael portal
The Michaelportal, the central portal of the north transept facade, has been restored since 2013. Between 1878 and 1881 , sculptor Peter Fuchs created an extensive range of sculptures for the neo-Gothic portal . This was particularly badly damaged by splinters and ricochets during World War II , so that many of the 250 figures were severely mutilated and left without a head or attributes. Some stones were so badly damaged that even the restorers could hardly touch them.
For the renovation, the Dombauhütte set up a stone restoration workshop in 2013, which uses the latest technology to restore the sculptural decorations. The restorers first clean the figures with a laser , which evaporates the black crusts of dirt from the stones, but leaves the stone itself undamaged. Since a large part of the figures cannot be removed, cleaning takes place directly at the portal. The missing parts of the sculptures are remade by the stonemasons . To do this, you can use the original clay models by Peter Fuchs, which survived the war. The color of the newly carved white additions can be distinguished from the laser-cleaned originals, which appear slightly yellow.
A new approach was also developed for restoring the canopies . The canopies in the archivolts are the most elaborate pieces of portal decoration because of their complex geometric shape and their ornaments. It takes a stonemason around a year to create a new canopy. Thanks to the use of modern technology, the Bauhütte succeeded in completing the damaged canopies with millimeter-precise additions (so-called crossing ) and thus keeping them in their original substance.
Choir band wreath
The wreath of the choir chapels is the oldest part of the cathedral. It was built between 1248 and 1261 from trachyte stone extracted from the Drachenfels quarry . In 2018, the Dombauhütte began an investigation into how this component can be restored. Around 90 percent of the original masonry is still preserved; The original surfaces with tool marks and pliers holes can still be seen on some stones. In the northernmost chapels, the stones were cleared of vegetation and crusts; the condition of the stones is mapped. A restoration concept is currently being developed, which is being worked out in exchange with the construction huts in Xanten and Utrecht . These two churches were also largely built from trachyte in the Middle Ages.
Trades
Around 100 craftsmen from various trades are employed in the Dombauhütte. They are coordinated by the smelter, who is responsible for planning the construction sites. Uwe Schäfer has been the technical director of the Dombauhütte since 2002.
Stonecutters
Traditionally, the stonemasons are the numerically largest group within the construction works. In the Middle Ages, the cathedral builder was also chosen from among their number. Then as now, the stonemasons are responsible for producing all the architectural workpieces for the cathedral construction. It is up to you to shape the cuboids for the rising masonry and to design the tracery for the windows, parapets and buttresses . With the leaf ornaments, they are usually based on a plaster model that the stone sculptors modeled.
Today the work pieces are milled with a stone saw so that they are already flat and at right angles and prepared for further processing. The elaboration of profiles and shapes carried further by hand, with the stone masons today both modern pneumatic chisel and traditional hand chisels and hammers use.
In order to bring a workpiece into the desired shape, an axis cross is drawn on the appropriately sawn cuboid, with which the templates for the jewelry shapes can be aligned. The lines of the profile courses are drawn in with a pencil; The stonemason orientates himself on them when he executes the surfaces and profiles. The shapes from which the foliage are finally chiseled initially remain as rough angular shapes, the so-called sculptor bosses.
Stone sculptor
Cologne Cathedral has around 1500 statues from the 19th century. It is one of the largest ensembles of neo-Gothic sculpture. The main artists involved were Christian Mohr and Peter Fuchs . Due to the influences of the weather, but also due to the destruction of the Second World War , numerous figures have been damaged, which are continuously repaired by the Bauhütte, whereby lost or destroyed parts often have to be replaced. For this purpose, the stone sculptors make models from plaster, which the stone masons use as templates.
In order to replenish the destroyed figures, the stone sculptors use old draft drawings. You can usually fall back on one of the 700 models that the sculptors Mohr and Fuchs had made on a smaller scale. The sculptors model the figures on a 1: 1 scale, but when enlarging they have to make sure that the expression and detail impression match the torso that is to be added. With the help of a puncturing device , the model is then accurately transferred to the stone.
Stone masons
The stone masons are a younger trade. In the Middle Ages it was the same stonemasons who, when the weather was good, moved the stones on the structure that they had chiseled into shape when the weather was bad. Today the masonry masons have specialized in assembling and dismantling the workpieces. They are also responsible for renewing the joints between the stones and replacing corroded dowels and retaining anchors. The joints between ashlar are usually made of lime mortar. On filigree components, such as eyelashes or tracery windows, the joints are filled with lead , as was customary in the Middle Ages.
If several workpieces have to be moved, the stone masons proceed in the same steps as the builders in the Middle Ages. The workpieces have a dowel hole on the top and bottom; A metal dowel, which today is made of stainless steel, is placed in the lower hole of the upper stone. Then the upper stone is slowly moved so that the dowel fits into the lower dowel hole. Finally, the craftsmen seal the joints between the stones with clay and then pour them with lead.
Stone restorers
In 2012, a stone restoration workshop was set up in the Bauhütte. The restoration team includes experts who specialize in surface treatment, restoration and monitoring . Their task is to identify decrepit structures - especially in the trachyte rock -, to stabilize them again and thereby preserve them in the long term. The medieval trachyte from the Drachenfels today shows in its intact condition a black colored plaster crust. At the edges and joints, however, water can penetrate, as a result of which the stone shows severe weathering, and it then appears white and washed out. The stone restorers try to consolidate these areas, backfill the damaged areas, use a syringe to inject color-matched mortar into hairline cracks and cavities, supplement the stone with restoration mortar and finally grout the stones. In this way the water can run off the stone and it is protected.
In addition, the restorers ensure that sculptures are cleaned while preserving their substance as much as possible, stabilized if necessary and sculpted where necessary. The restorers clean the stone figures with laser devices that are gentle on the surface . With the help of 3D scanners , the restorers can determine exactly how large the defects are. Additions can then be modeled precisely for the break points. Photographers document the inventory and project progress in detail and digitally map them. Through the complete documentation, the work should remain traceable for posterity so that the success and failure of measures can be checked in the long term.
Stained glass restorers, glass painters and art glaziers
The approximately 10,000 square meter Cologne cathedral windows are also exposed to weathering. For this reason, a separate workshop was set up in 1953 for glass restoration, which completely overhauled the picture cycles and recreates others based on historical models. The Dombauhütte's glass restoration workshop is one of the most modern in Europe.
The glass paintings suffer from precipitation, condensation and the pollutants in the air. At the same time, glass also tends to lose its consistency after centuries, which especially threatens the windows of the high choir from the 14th century. Over centuries, fluctuating temperatures and the alternation of dryness and humidity caused small cracks in the glass, through which pollutants can penetrate. The glass corrodes when acid protons from the rainwater move into the glass and at the same time alkali ions are washed out of the glass. These come from the lime or potash that the glassmakers added to the mixture in the Middle Ages in order to lower the melting point.
When glass is restored, the first step is to remove dust, soot and crusts of dirt that have accumulated on the glass surface over decades. Fungal spores also nestle on the rough surface of the medieval jars. These are carefully removed with soft brushes, cotton swabs and occasionally with fine scrapers; chemical cleaning agents are too harsh and have not proven their worth. The iron red and silver yellow dyeings used in the late Middle Ages are particularly sensitive. Where necessary, the restorers glue cracks in the pieces of glass, straighten and stabilize the lead mesh and reverse unsuitable measures from previous restorations. In order to protect the panes permanently, protective glazing made of safety glass is placed outside the work of art. This means that the glass pictures will remain dry in the future and are protected in the interior.
Colored glasses
Painting
In the lead network
cleaning
The glass painters and artifacts in the glass workshop are working to completely reconstruct lost and badly damaged windows. Based on an artistic draft, cardboard boxes are created that define the size, shape and colors of the panes. The cardboard is cut into stencils with stencil scissors. The scissors have three blades and save the strip when cutting, which is later filled by the lead net. To cut the pieces of glass into the right shape, crumbling pliers were used in the High Middle Ages and a diamond cutter was used since the 14th century. Today a glass cutter with a steel wheel is used for this. If the draft allows, the panes are painted and fired. The panes are then framed by a lead net made of H-shaped lead rods, which is soldered at the crossing points.
In 2003, the Bauhütte began to complete the 28 windows of the so-called World Heritage Cycle, based on historical templates. The Welter cycle consists of windows in the upper storey designed by Michael Welter in the 19th century , of which 15 were completely destroyed and 13 in parts during the Second World War.
Scaffolders
The cathedral supports almost uninterrupted scaffolding so that the restorations can be carried out. These scaffolding are always custom-made by the Dombauhütte, because the cathedral, with its overall height and the extensive facade decoration, requires special constructions that should not damage the structure. Therefore, the Dombauhütte employs five scaffolders.
Spectacularly visible from afar and is the cradle hanging from 2011 to the towers and was designed to be the Fialtürme to restore. The scaffolding is 30 meters high and consists of particularly light aluminum profiles that are otherwise common in stage construction. It is constructed in such a way that it can be hung on the tower spire with a large ring and otherwise just lean against the masonry.
roofer
The cathedral has a roof area of around 12,000 square meters, which is covered with lead . The choir, completed in 1322, was covered with lead; the soft, flexible material with its high dead weight is still the preferred material for covering the cathedral. Lead is easy to work with and, due to its high weight, can withstand severe storms. During the Second World War, around 80 percent of the roof area was destroyed and, after the war, first patched with zinc sheets. Since 1985 the Dombauhütte has been working systematically to renew all roof areas. After the high and side aisle roofs have meanwhile been re-covered, work on the roofs of the choir chapels and the ambulatory is now pending. In addition, it is the task of the roofers to maintain the complex pipe system, which, with a total length of around ten kilometers, diverts the rainwater from the building.
Locksmith and blacksmith
The only open smithy fire in Cologne city center is maintained in the Dombauhütte. The blacksmith is one of the traditional craftsmen of the building works and is still indispensable today. Dowels, brackets and anchors have been important construction elements since the Middle Ages for moving the stone and fixing the building decorations. Because iron fasteners tend to corrode, they are forged from stainless steel today. In addition, the metal workers also develop and maintain the structures for lightning protection. In addition, they invent suspensions for lamps, loudspeakers and works of art that do not require any drilling if possible.
Carpenter
The carpentry of the cathedral building has a special wealth of experience in working with solid wood. Among other things, she maintains the 456 wooden doors, the 230 pews, the confessionals and all wooden furnishings in the cathedral. In addition, the joinery constructed the crossing podium and the choir podium.
Stones on the cathedral
Around 50 different types of rock were used in the construction of the cathedral. This unexpectedly high number of different building materials can be explained by the long construction time and the repeated and ongoing renovation work. The most important stones of the rising masonry include the trachyte from the Drachenfels , the Stenzelberg trachyte, the Schlaitdorfer sandstone , the Obernkirchener sandstone , shell limestone from the Main, basalt lava from the Eifel and Londorfer basalt lava . As in the Middle Ages, stone masons prefer the soft limestones from Savonnières and Caen for sculpting work . The builders of the Middle Ages built the particularly stable foundation from columnar basalt , tuff stone and lime mortar.
Awards
- 2019: A stone on the board of the Professional Association of German Geoscientists
See also
literature
→ Main page: Bibliography on Cologne Cathedral
- Arnold Wolff: The endangerment of the cathedral and the work of the Dombauhütte. In: Arnold Wolff, Toni Diederich: The Cologne Cathedral reading and picture book. Cologne 1990, pp. 73-87.
Web links
Individual evidence
- ↑ dombau-koeln.de - Info.
- ↑ dombau-koeln.de: Dombauhütte history.
- ↑ Johann Josef Böker: Michael von Savoyen and the facade of the Cologne Cathedral, Cologne 2018, p. 109f.
- ↑ focus.de - sculptor and stonemason.
- ↑ Koelner Dom.de: History of the Cologne Dombauhütte.
- ^ Arnold Wolff: The perfect cathedral, p. 43f.
- ^ Johann Josef Böker: Michael von Savoyen and the facade crack of the Cologne Cathedral, Cologne 2018, p. 115.
- ↑ stadtgeschichten-stadtfuehrungen.koeln: Cologne Cathedral - giant made of stone The figures are not documented, but result from today's experience of the cathedral builders in Cologne, Strasbourg and Regensburg
- ↑ stadtgeschichten-stadtfuehrungen.koeln: Cologne Cathedral - giant made of stone The figures are not documented, but result from today's experience of the cathedral builders in Cologne, Strasbourg and Regensburg
- ↑ stadtgeschichten-stadtfuehrungen.koeln: Cologne Cathedral - giant made of stone
- ^ Johann Josef Böker: Michael von Savoyen and the facade crack of the Cologne Cathedral, Cologne 2018, p. 100ff
- ↑ a b c planet-wissen.de: the Dombauhuette.
- ^ A b Arnold Wolff: The endangerment of the cathedral and the work of the cathedral builder. in: Arnold Wolff, Toni Diederich: The Cologne Cathedral reading and picture book. Cologne 1990, p. 80.
- ^ A b Eduard Firmenich-Richartz : Ahlert, Friedrich (Adolph) . In: Ulrich Thieme , Felix Becker (Hrsg.): General Lexicon of Fine Artists from Antiquity to the Present . Founded by Ulrich Thieme and Felix Becker. tape 1 : Aa – Antonio de Miraguel . Wilhelm Engelmann, Leipzig 1907, p. 142 ( Textarchiv - Internet Archive ).
- ^ Arnold Wolff: The completion of the cathedral in the 19th century. In: Arnold Wolff, Toni Diederich: The Cologne Cathedral reading and picture book. Cologne 1990, p. 50.
- ↑ Siegrid Brandt: Creative preservation of monuments? Notes on a swear word. In: Kunsttexte.de 1/2003 (edoc.hu-berlin.de)
- ↑ Moritz Küpper: Permanent construction site Cologne Cathedral - not a day free of scaffolding for over 100 years. On: deutschlandfunkkultur.de
- ^ Arnold Wolff: The Cologne Cathedral, edited and supplemented by Barbara Schock-Werner, Cologne 2015, p. 14.
- ^ Arnold Wolff: The Cologne Cathedral, edited and supplemented by Barbara Schock-Werner, Cologne 2015, p. 52.
- ↑ deutschlandfunkkultur.de Permanent construction site in Cologne Cathedral for over 100 years not a day without scaffolding.
- ↑ express.de: At Koelner Dom there is even the FC Geissbock made of stone
- ↑ Barbara Schock-Werner: 45th Cathedral Report, October 2003-September 2004, p. 10
- ↑ zeit.de: Pope Francis looks down from Cologne Cathedral
- ↑ Kölner Stadt-Anzeiger: Stone figures Barbara Schock-Werner and Norbert Feldhoff adorn the cathedral.
- ↑ catholic.koeln: City dean Robert Kleine congratulates and honors Dompropst Gerd Bachner on his 75th birthday
- ↑ Hüttenmeister Uwe Schäfer in a Focus interview. focus.de - sculptor and stonemason.
- ↑ focus.de - sculptor and stonemason.
- ↑ Barbara Schock-Werner: 46th cathedral report October 2004 - September 2005 , p. 28ff
- ↑ Domradio.de , accessed on February 16, 2020.
- ↑ deutschlandfunkkultur.de: Permanent construction site Koelner Dom has not been scaffolded for over 100 years
- ↑ zdv.de: Angel to the north tower
- ↑ Domradio.de, accessed on February 16, 2020
- ↑ koelner-dombauhuette.de - building maintenance
- ↑ koelner-dombauhuette.de - building maintenance
- ↑ koelner-dombauhuette.de: Bauerhalt
- ↑ Dombau-Koeln.de: The Michael portal of Cologne Cathedral
- ^ Aachener Nachrichten.de: Restoration workshop for cathedral portals opened
- ↑ Michael Hauck: 54th cathedral report October 2012 - September 2013 p. 85f
- ↑ Peter Füssenich: 55th Cathedral Report October 2013 - September 2014 , p. 20
- ↑ Express.de: Laser cure for 250 figures of the Michael portal
- ^ Albert Distelrath: The partial additions to baldachins from the Michaelportal - a work report , in: Kölner Domblatt, 84th episode, 2019, p. 59ff
- ↑ koelner-dombauhuette.de Building maintenance
- ↑ www.faz.net Koelner Dombauhuette.
- ↑ Kölner-dom.de: Dombauhütte
- ↑ a b c d e f g h i j Schautafel, Dombauhütte, Open Day, documented on September 7, 2019.
- ^ Hiltrud Kier: Reclams City Guide, Architecture and Art Cologne, Stuttgart 2008, p. 51.
- ↑ faz.net - Stonemasons at Cologne Cathedral Filigree work for eternity.
- ↑ kathisch.de It is a world event.
- ↑ dombau-koeln.de Restoration workshop opened.
- ^ A b Arnold Wolff: The endangerment of the cathedral and the work of the Dombauhütte, in: Arnold Wolff, Toni Diederich (Ed.): The Cologne Cathedral Reading and Picture Book, Cologne 1990, p. 84f.
- ↑ a b Cologne Cathedral Treasury: Close to it, the Christ window in Cologne Cathedral, brochure for the exhibition in the Cathedral Treasury, September 2019.
- ↑ gdv.de: Workplace at a height of 157 meters
- ↑ Barbara Schock-Werner: 52nd Cathedral Report October 2010 - September 2011 , pp. 140f
- ↑ Rundschau online: the roofer from Cologne Cathedral
- ^ Arnold Wolff: The endangerment of the cathedral and the work of the Dombauhütte, in: Arnold Wolff, Toni Diederichs: The Cologne Cathedral reading and picture book, Cologne 1990, p. 73ff
- ^ Grandi quarries: Cologne Cathedral access building
- ↑ 11th German Geologists' Day. Professional Association of German Geoscientists, accessed on October 23, 2019 .
- ↑ 11th German Geologists' Day. Professional Association of German Geoscientists, accessed on October 23, 2019 .