Athens, Greece

The Stavros Niarchos Foundation is one of the world’s leading private, international philanthropic organizations, making grants in the areas of arts and culture, education, health and sports, and social welfare. The Stavros Niarchos Foundation Cultural Center project designed by renowned architectural firm, Renzo Piano Building Workshop, included the construction of new facilities for the National Library of Greece and the Greek National Opera, as well as the creation of the 210,000 m² Stavros Niarchos Park.

Project Requirements

A project of this concept and magnitude in any country sets high demands, and is assured of close public and technical scrutiny on almost every level, from the very beginning, through to its final handover and beyond. Sika provided help and assistance in every phase of the project, both by proposing the most appropriate materials and systems based on the specifications, as well as via practical technical evaluations and support on site. This included using Sika’s global experience and technical expertise to advise on innovative solutions to save both time and cost, plus to increase durability and thereby the project’s service life and sustainability. Sika provided materials and systems literally from the foundations to the roof, which not only met the project’s requirements in terms of  technical specifications, but also in terms of sustainability and  environmental impact requirements.

Project Participants

Stavros Niarchos Foundation

Renzo Piano Building Workshop, Betaplan

Expedition, Omete

Sika Organization
Sika Greece

Greek National Opera

The Greek National Opera at the Stavros Niarchos Foundation Cultural Center

The Greek National Opera (GNO) is designed as a multi-use venue capable of hosting a variety of different performances and events. The new 28,000 m2 auditorium is an architectural jewel, designed to enhance the opera experience for the patrons and artists alike. Its world-class acoustics, enhanced performance capabilities with flexible staging, and its own innate beauty positions it for immediate entry into the world opera circuit. It is now ready to play host to the most technically demanding operas, international multimedia art productions, and their formidable vocalists.

National Library of Greece

National Library of Greece lobby marble flooring

The new building for the National Library of Greece (NLG) modernized the institution founded in 1832, allowing it to strengthen its research role whilst expanding its focus to be an all-inclusive public resource. In its new and enlarged role, the library supports patrons of all ages and education — from academic researchers to children and young adults destined to become the next generation of users. The nearly 24,000 m2 state-of-the-art building combines traditional materials with technological innovation, conservation with information and communication in a flexible design.

Stavros Niarchos Park

Stavros Niarchos Park

The Stavros Niarchos Park is a vital green space linked by an ecological concept, which functions as the gateway into the new National Library of Greece and the new Greek National Opera House. The spectacular features of the Stavros Niarchos Park are not all at ground level. Soaring 14 meters above the main building structure, there is a photovoltaic canopy that is almost 100 x 100 meters across. An engineering wonder, supported by only 40 sinewy thin steel columns, the canopy makes a unique and fascinating addition to the city skyline.

Sika Solutions for the Stavros Niarchos Foundation Cultural Center

Water reservoir canal next to Stavros Niarchos Cultural Center
Canal Waterproofing

The new canal in the park was waterproofed using a reinforced, built-up Sika sheet membrane system inside the new structure. This Sika system also enabled the engineers to ensure fully watertight connections, joints and terminations, by connecting it directly to the retaining concrete structures using Sika® Waterbars and Sika engineered waterstops. Sikaplan® membrane was selected in order to ensure the complete water tightness of the canal construction and the roughly 15,000 cubic meters of water it contains.

The Stavros Niarchos Foundation Cultural Center below ground waterproofing injection hoses
Below Ground Waterproofing

In a project of this magnitude, waterproofing below ground to protect the structural foundations and create a water resistant structure was of utmost importance. The Sika watertight concrete system for below-grade structures included:

  • Waterproof concrete prepared using special Sika water resisting admixtures
  • Sika engineered jointing systems, including Sika® Waterbars, plus additional Sika waterstops, such as SikaSwell®-A water swelling profiles
  • Built-up Sikaplan® WP-1100 15HL sheet waterproofing system, incorporating geotextiles and integral drainage layer for the deep basement
  • Special SikaFuko® VT-1 injection hoses for easy re-injection and sealing in case of any future ground movement at the diaphragm walls
The Stavros Niarchos Foundation Cultural Center structural and architectural concrete construction
Structural and Architectural Concrete

Approximately 150,000 m3 of 10 different classes of structural and architectural concrete with different technical characteristics were required. Technical performance and placement along with architectural concrete (especially fair-faced area) aesthetic requirements - uniform color and smoothness - had to be met. Sika admixtures were incorporated into all concrete mixes. Final fair-faced concrete mix designs were based on self compacting concrete using Sika® ViscoCrete® Ultra-600 superplasticizers with Sika® Stabilizer®-4R viscosity modifiers. Sika® Separol® W-320 and Antisol® systems were used for demolding and controlled water evaporation from curing concrete surfaces.

Seismic isolation system with cementitious grout for the Stavros Niarchos Foundation Cultural Center
Seismic Isolation Systems

The new opera and library buildings are built on specially designed seismic isolation systems placed between vertical bearing elements and building foundations. These seismic isolators form an alternative, practical method for the seismic reinforcement, as they can significantly reduce the stress that the structure would be subjected to in an earthquake. For the seismic isolator installation, a special one-component, fiber reinforced, cementitious grout from the SikaGrout®-312 RFA range was selected.

Green roof construction of Stavros Niarchos Cultural Center
Roof Waterproofing

For all flat roofs on this project, the most appropriate system was selected from the fully comprehensive Sika range of roof deck waterproofing systems. For the single-ply membrane roof build-ups, this was Sarnafil® TG 66-20 - multilayer, anti-root, synthetic roof waterproofing sheet based on premium-quality flexible polyolefins (FPO), reinforced with an inlay of non-woven glass fabric according to EN 13956.

Ferrocement canopy construction at the Stavros Niarchos Foundation Cultural Center
Ferrocement Canopy Method

The new Greek National Opera building is covered by a huge canopy envisioned by the architect to hover above like a cloud, being both part of it and separate at the same time. This fabulous feature is one of the most important elements of the project design, both architecturally and structurally. This canopy had to be lightweight and compact with a perfectly smooth and continuous surface, which led to the selection of an unusual material for the canopy - ferro-cement. Ferro-cement is a thin, composite material that can be easily molded for lightweight structures, but not normally done on this scale nor for such structural applications. The Stavros Niarchos Cultural Center construction project was the first time worldwide that it was used for building on this scale, especially as a structural element!

For such high quality ferrocement construction, the design and performance of the cement mortar was of critical importance. Sika engineers and concrete technicians provided assistance from the very beginning through to successful completion on site - including detailed raw material analysis, mix design and testing in the laboratory and on site.

"The Stavros Niarchos Foundation Cultural Center was the first project worldwide that used ferro-cement for building on this scale, especially as a structural element!"
Ferrocement canopy waterproofing for the Stavros Niarchos Foundation Cultural Center construction
Ferrocement Canopy Waterproofing

The 10,000 m2 ferrocement canopy itself was a unique, pioneering project. The selected waterproofing system was liquid applied, polyurea resin-based membrane system Sikalastic®-8800, which was spray applied onto the primed surface using two-component, hot spray equipment. A protective, polyurethane resin-based, highly UV resistant, top coating of SikaCor® EG-5 was then applied. Finally, the waterproofed surface of the ferrocement canopy was covered with photovoltaic panels, which contribute to the project's sustainability, significantly reducing its CO2 footprint.

Car parking garage floor of the Stavros Niarchos Foundation Cultural Center
Car Parking Garage Flooring

The multi-story, underground visitor parking facility with about 40,000 m2 of dedicated parking spaces had concrete deck surfaces which needed protection from abrasion and wear. Polyurethane and epoxy deck coating systems from Sika were ideal and applied throughout the car park. A special Sika polyurethane resin-based system was specified - Sikafloor® MultiFlex PB-21 UV - which is a highly aesthetic, anti-slip, crack bridging flooring system featuring high resistance against abrasion and noise minimization qualities. On the parking area under the opera, the uniform color, epoxy roller-coating system Sikafloor® MultiDur ES-14 was applied. All Sikafloor® systems carry a LEED attestation regarding VOC content.

National Library of Greece lobby at the Stavros Niarchos Foundation Cultural Center
Elastic Sealing and Bonding

The use of highly aesthetic wood flooring was a must for the opera building and this was installed using the elastic, one-component, polyurethane resin adhesives from the SikaBond®-54/-52 Parquet range. All concrete floor joints and building facade joints in concrete substrates were sealed and made watertight using Sikaflex® WS-355 polyurethane resin-based sealants. Sealing the natural white marble stone floor and wall tile joints was done using a special one-component, silicone resin-based Sikasil® WS-355 sealant, which is approved for contact with natural stone and does not stain.

Products Used

Concrete Production

540 tons superplasticizer Sika® ViscoCrete® series
29 tons superplasticizer Sika® ViscoCrete® Ferro-1000
61 tons waterproofing admixture Sika®-1+
123 tons silica fume SikaFume®
10.5 tons stabilizer Sika® Stabilizer
130 tons retarder Sika® Plastiment
29 tons evaporation control membrane Sika® Antisol®
2.7 tons curing membrane Sika® Antisol®
5 tons demolding agent Sika® Separol®


200 meters of injection hoses SikaFuko® VT-1
4.2 km seawater swellable profiles SikaSwell® A-2010M
2.6 km swellable profiles SikaSwell® A-2010 / A-2005
750 cartridges of swellable sealant SikaSwell® S-2
4.7 km Sika® Waterbars
2.75 tons cementitious waterproofing mortar SikaTop® Seal 107
4,100 m2 PVC waterproofing membrane Sikaplan®
15,400 m2 PVC waterproofing membrane Sikaplan® WP (Blue-UV stabilized)
480 m2 drainage membrane Sika® Drain-S
20,100 m2 geotextile S-Felt A 300 F
13,700 m2 geotextile S-Felt GK 400
24 tons sprayed liquid-applied membrane (LAM) Sikalastic®-8800

Roof Waterproofing

2,900 m2 bituminous roofing felt Sika® Bituseal
1,800 m2 FPO membrane Sarnafil® 2 mm
36,520 m2 FPO membrane Sarnafil® TG 66-20
680 m2 PVC membrane Sikaplan® 1.5 mm
500 kg sprayed liquid-applied membrane Sikalastic®-612
320 m2 adhered FPO membrane Sarnafil® 1.2 mm

Repair Mortars, Anchoring and Grouting

2 tons cementitious repair mortar Sika MonoTop®-627
2 tons cementitious repair mortar Sika MonoTop® Dynamic
2 tons cementitious repair mortar Sika MonoTop®-621 Evolution
1.8 tons Sikadur® Epoxy Mortar
112 tons cementitious grouts SikaGrout®
5,784 kg epoxy chemical anchors Sika AnchorFix®-3+
4.65 tons protective coating SikaCor® EG-5

Elastic Sealing and Bonding

5,680 sausages of elastic polyurethane-based sealants for facade joints Sikaflex® AT Facade / Construction+ / SikaHyflex®-250 Facade
146 liters of epoxy primers Sika® Primer-3
6,800 sausages of elastic polyurethane-based sealants for floor joints Sikaflex® Pro-3
417 cartridges of special silicone for natural stone Sikasil®
1.62 tons cementitious tile grout SikaCeram® CleanGrout
3.7 km joint backer rod Sika® Backing Rod
2,315 cartridges of multipurpose sealant and adhesive Sikaflex®-11 FC+
4,800 sausages of engineered silicone Sikasil® WS
1,300 cartridges of fire-rated sealant EverBuild Fire Sealant-300
5 tons of elastic wood floor adhesive SikaBond®-54 Parquet
950 sausages of elastic wood floor adhesive SikaBond®-52 Parquet

Industrial Flooring

200 tons dryshake hardener Sika QuartzTop – Chapdur® Premix
4 tons epoxy primer Sikafloor®-156
7 tons epoxy primer Sikafloor®-161
33 tons polyurethane deck coating Sikafloor®-375
17 tons polyurethane top coat Sikafloor®-359 N
9 tons epoxy deck coating Sikafloor®-264