At first glance, the new warehouse of the gin and whisky distillery seems to be clad with old, charred wooden planks. In reality, the barrel store of the Kyrö Distillery in the north of Finland has a jet-black pigmented and structured concrete façade. It is colored with Bayferrox-brand inorganic pigments from specialty chemicals group Lanxess and was awarded the Finnish Concrete Architecture Prize. The stylish building was designed by the architectural office Avanto Architects.

It all started with a “crazy idea”: Five Finnish friends founded the Kyrö Distillery Company on a sauna raft, which started its business in 2014 in an old dairy. The distillery won many international awards, and with the fame the demand for the spirits increased rapidly - the existing production capacities became scarce. Kyrö then organised an invitation competition for the overall design of the old dairy site. Avanto Architects (Avanto Arkkitehdit Oy) was selected to design a master plan and several new buildings and to convert the old historic buildings on the factory site. The first step was to build a 1,056 m² black warehouse in the middle of the forest, inspired by traditional wooden barns. Four identical halls are to follow.

Sandwich elements with wooden structure

The outer wall structure of the already built warehouse consists of 4.5 to 6 x 3 m sandwich elements. The outer shell is 105 mm thick and reinforced with stainless steel. The concrete corresponds to the exposure class XC3.4, XF1. The inner shell consists of 80 mm reinforced concrete. Added to this is the insulation of 150 mm polyurethane.

The outer shell with the appearance of a plank floor, typical for the Finnish region of Ostrobothnia, is the special feature of the building. For the production of the façade elements, the commissioned precast concrete company Tara-Element relied on the support of the mould manufacturer Finn-Form. Boards from a dismantled barn were used as a template for the façade form liners. Matching pieces were selected and arranged in such a way that as few repetitions as possible resulted.

Two different moulds, each measuring 1,500 × 4,500 mm, normal and upside down, create a pattern that is repeated every six metres. Almost 1,000 kg of casting resin from France were used to produce the façade form liners.

The supreme discipline of “black concrete”

“Originally, the concrete elements were to be produced with colored concrete and then repainted even darker at the construction site,” reports Oliver Fleschentraeger, Market Segment Manager Construction in the Inorganic Pigments business unit at Lanxess. “After a few castings, the deep black Lanxess pigment Bayferrox 360 was used in a dosage of 5 % - this meant that a subsequent coat of paint was not necessary.”
The use of inorganic iron oxide pigments in concrete or the implementation of individual color ideas requires fundamental technical and application know-how - especially the use of black pigments. “Making really black concrete is the supreme discipline,” says Fleschentraeger. Whether the concrete has the desired color shade in the cured state depends not only on the quality and mixture of the color pigments, but also on the type of cement and concrete aggregates used.

The planners also received concrete assistance from the pigment manufacturer in the realisation of the barrel storage facility. One of the materials used was a white cement from Finnsemente Oy in Finland, which helps to create the desired color shade. The result speaks for itself: The dyed and profiled concrete imitates the weathered timber in a deceptively realistic way. The architects were awarded the Finnish Concrete Façade Architecture Prize at the end of 2019 for the new Kyrö Distillery barrel store.

Lanxess increases black pigment capacity

End of November 2020 specialty chemicals company Lanxess announced that is has expanded its capacity for black synthetic iron oxide pigments at its Krefeld-Uerdingen site by more than 5,000 metric tons per year.
In architecture and landscaping, the black coloration of concrete has been a trend for some time now. Concrete is a creative material, which provides a multitude of possibilities to building material producers, architects, and building contractors. With the use of suitable pigments, this applies not only to the architectural design of concrete, but especially to its coloration.

Lanxess is thus continuing the systematic expansion of its production capacities for synthetic iron oxide pigments. Lanxess is the only supplier worldwide to produce these pigments using the Laux process.