Curved curtain wall without refraction - special location, special solutions

Prefabricated concrete cladding was used on the lower floors, as in the previous twin building, but on the upper floors the investor chose a product with the same appearance but using a different technology: an Alubond composite panel was used for the façade. This is the reason why, whereas the façade cladding of the first building was applied using a bonded technique, here a separate support structure was applied to the concrete surface, thus creating an assembled structure. A hydrophobicised, cascaded rock wool insulation was applied under both the concrete and the composite slab, thus making the external façade watertight.

Anti-glare glass for safety

An additional difficulty was the curved curtain wall that partially surrounds the seventh floor and completely surrounds the sixth floor, which also took a long time to produce. As this was not a flat glass surface, the contractor had to pay particular attention to eliminating light refractions.

A thermal-bridge-free curtain wall with Schüco-style lysine-fin façade elements, typically double-layered, sometimes with solar control glass, was installed. The seventh floor of the building is a skybar and gym, where there are no longer hotel rooms, allowing visitors to enjoy the view of the planes taking off through the sunscreen without being obscured.

"As the products had to comply with the special security requirements of the airport, the installation of anti-glare glass surfaces was a key requirement, but sound insulation was also an important factor" - emphasized Ferenc Horváth, project manager.

The glass has been coated to significantly reduce glare, and careful attention has been paid to the construction of the windows to ensure sound and thermal insulation.

Sectoral tasks

While the existing hotel was built with a metal railing, the new hotel was fitted with glass railings on the connecting bridges and skybar area; the attic, mechanical space and skybar were fitted with a traditional carpentry and tin roof fixed to a steel structure. Here, Rheinzink tin sheeting, a very rare solution for new buildings, was installed on a timber support structure - it also gives the building a special character. In addition to the composite, concrete and Rheinzink facades, the inner courtyard (which is open from the first floor to the bridges) is covered with dryvit facade insulation in white.

"We did the rainwater drainage on the mechanical level, but the thermal envelope also included the complete external waterproofing of the building and the groundwaterproofing on the outside"

- said Csaba Czunyi and Ferenc Horváth, adding that the confluences had to be connected to the system. They also had to integrate the wastewater outlets with two transfer pumps into the base plate.

On the electrical side, the SWIETELSKY Magyarország was also responsible for the reinforced concrete structure's protective piping, the earthing network, the lightning protection and the installation of eight infrared obstacle light lamps, which were required for the aircraft. Additional padlock structures were also built, typically associated with mechanical structures.

They were fighting serious winds

"We had to be free of condensation by the end of June, which we achieved a little earlier"

- stressed Ferenc Horváth, project manager. This was one of the big milestones the contractor had to jump, the next big step was the deadline.

They have struggled a lot with the weather - especially when it comes to structural construction, inverted and straight-ply roofs and tin roofing. When the wind blows, it is more noticeable in this open area than in an urban environment. This was also a problem with the tower cranes, because they could not be used above a certain wind speed, so forced outages made work difficult.

"Of course, we had more space here than at a downtown construction site, but we still faced challenges in the staging area, because sometimes two or three slab materials were on site at the same time due to the good utilization of production capacity" - Csaba Czunyi listed the complicating circumstances.

In addition to these, it was a real success when the building was ready at the gates of Liszt Ferenc Airport by the end of May 2024.

Character relationship

The two hotels are connected by a single-storey reinforced concrete span, which, although connected to the base slab of the partially basemented building, is structurally separated from it due to the movement of the buildings. This corridor, which widens into a lobby in the middle, will be the new common entrance to the hotels.

"Anyone entering the ground floor lobby - Ferenc Horváth explained in detail - will meet the central reception, in front of which we have also built a concrete canopy. From here, you can head towards the TRIBE or ibis Styles hotel."

In order to build it, they had to demolish the facade of the ibis hotel and block the opening to guests with a temporary wall. "A curtain wall façade has been and will be built at the opening, as the final entrance will be possible in the first quarter of 2025," added Ferenc Horváth.

In the same way, the façade could not yet be closed, because a temporary lift was installed on a section of the façade for the transport of materials, which can only be removed once the internal lifts are finally installed. Despite these minor problems, the technical handover of the building could already start on 15 November, so that SWIETELSKY Magyarország, responsible for the structure and shell & core works, could gradually hand over the work area, level by level, to the company responsible for the interior works.