Summaries

Sveti Stefan, a church with decorations all over its facade on the coastal road of Fener-Balat in Halic, Istanbul. This church has two more known names: “Iron Church” or “Bulgarian Church”.

Iron Church, owned by the Bulgarian Orthodox Churches Foundation, is a structure with its frame and all members built of iron. Its outer walls, buried footings, window frames, door leaves, arches, columns, eaves, roof, in other words any part of the building was manufactured out of cast-iron sections, sheets and forged iron which were connected to each other through bolts and nuts, rivets or welds.

Sveti Stefan Bulgarian Church was opened to service with the participation of Bulgarian and Turkish Presidents in January 2018 after the completion of the recent renovation works. It is known that three iron churches had been built around the world; in Argentina, Austria and Turkey. Only the iron church in Turkey survived as of today. The Iron Church with the renovation works ongoing for seven years is absolutely a very valuable structure for the structural steel industry in Turkey.

The church was designed as two separate projects by an Armenian architech, Hovsep Aznavur, who had many works in the Ottoman period. The plan designed by the architect Hovsep Aznavur is composed of extending the high framed dome supported by four large columns extended by cradle vaults on four sides. This is a 19th century structure with an area of 365 squaremeters with semicircular arches in its facade, towers on both sides of the entrance, high dome and cradle vaults supporting the dome.

Technical difficulties emerged in the first attempt of laying the foundations in 1859 after the completion of the architectural design as the soil on the construction site was unstable. This is also one of the reasons why the church was constructed of iron. The structure was designed in iron as the unstable soil could not support the masonry structure observed in the churches of the time, and this material was preferred considering the seismic conditions and fast-track construction requirement. Another consideration was to have a prefabricated structure if the church was to be transported to another location. Piles were used for soil improvement. Wooden piles were driven into the ground, top portions of the piles were connected to each other and blocks of stone were placed on the piles. A layer of lime mortar was laid on top of the stone blocks and thus the soil improvement works were finalized in 1892.

During the execution of the soil improvement works, the production phase for the construction drawings was ongoing. An international competition was organized for the preparation of the construction drawings and R. Ph. Waagner from Vienna was announced as the winner of the competition. Manufacturing phase of the iron members started while the preparation of the construction drawings by Waagner drew to a close. Experiments were conducted on the manufactured members and the church was temporarily constructed in the factory yard. Materials manufactured in 1895 was delivered from Vienna to Trieste, then to Istanbul in ships over the Adriatic. 15 technicians also came to Istanbul for the erection of the structure. The construction of the structure was complete in 1896 and the opening ceremony for the church took place on 8 September 1898.

The first renovation works in the Iron Church, which was completed in 1898, took place in 1946. Repairs in majority on the exterior of the structure were made and the window profiles were painted. Whilst the church was on the seafront at the time it was built, problems start with its piles following the construction of a road on backfill in front of the church, and the structure began to move towards the Golden Horn. In 1985, an engineer from Bulgaria, Veselin St Venkov, came to Istanbul and prepared a report following his investigations. In 1988, Gilbert Wiplinger, an engineer from Austria, came to Istanbul and prepared a report on the soil movements and corrosion. Finally, renovation works took place in the Iron Church in 1991 directed by architect Sinan Genim. Exterior facade members which corroded and torn apart due to their connection to the foundations with many other elements including the roof covering were renovated.

In 2002, soil bores were drilled in addition to field tests and inspection pits. The soil improvement works took place in 2005 based on these investigations and the problems of movement and settlement of the Iron Church were solved. The most extensive renovation works after 2005 started in 2011. Following the completion of the works on a seven-year period, the Iron Church starts to shine again and maintains its existence as a valuable structure of Istanbul.