Built underwater in the ocean of the Coast of Norway
The Under Restaurant is a monolithic structure made from reinforced concrete. It is 34 m long and slopes away into the sea down to a depth of 5 m, where it rests on the seabed just off Lindesnes, the most southerly point of the Norwegian coast, around a one and a half hour drive from the nearest airport and five hours from Oslo.
The interior spaces of the restaurant are protected by a 1 m thick reinforced concrete shell designed to withstand the pressure of the water and the particularly harsh climatic conditions both above and below sea level. The designers decided to leave the exterior surfaces of the construction with a rough, exposed concrete finish to encourage the growth of seaweed and mussels below the waterline and to make the structure seem part of the rocky coastline where it is situated. Thanks to its particular location, the building is also intended to become an observation point to control the surrounding marine environment.
The structure is made from precast modules and is anchored to a block of concrete. A walkway links the rocky coastline to the entrance of the restaurant, which opens onto an interior space with a surface area of 600 m² over three levels descending into the sea. On the top floor, or “zero” floor, there is the reception and cloakroom, followed by a bar at the mezzanine level and then a lower floor where the restaurant, with seating for up to 100 guests, is situated.
The dining room has a panoramic window with a double layer of acrylic glass looking out directly onto the seabed.
Working below the sea level
Because of its special design and complexity, the project required a large range of high quality and technologically advanced products.
The products supplied included Confix*, Confix Fin* and Redirep 45 RSF* to repair the concrete, epoxy resin-based products and hi-flow mortars for anchoring elements in place (such as Mapepoxy BI*, Mapepoxy LR*, Mapepoxy L* and Nonsett 400*), Mapefix VE SF for chemical anchors, Mapeprimer M* epoxy primer for treating concrete substrates with surface moisture, Planitop Fine Finish ultra-fine-textured skimming compound for exposed concrete, Resfoam 1KM and Resfoam 1KM AKS* resin for waterproofing structures subject to intense water seepage and Superflyt* superplasticising admixture for mortars.
Utrabond MS Rapid adhesive was chosen for its high sucker effect and rapid setting properties to install the 3D ceramic tiles in the bathrooms.
In the spotlight
Ultrabond MS Rapid
It is a one-component, deformable, thixotropic adhesive with a high modulus of elasticity made from sililated polymers, characterized by its high initial tack and rapid final hardening. It is recommended for those bonds where a strong initial tack and high mechanical strength are required after a short curing time. It features rapid polymerisation and is especially suitable for bonding cement and cement-derived materials, bricks, stone, wood and wood-derived materials, metals, painted surfaces, ceramics, glass, rigid and flexible plastics.
1. The building was made from precast concrete modules.
2. The 3D tiles in the bathrooms were installed with Ultrabond MS Rapid.
3. The restaurant on the lower floor.
Technical data
The Under Restaurant, Spangereid (Norway)
Period of construction: 2018-2019
Period of Mapei intervention: 2018-2019
Design: Snøhetta
Client: Lindesnes Havhotell
Installation companies: Rencon AS, Murermester Arnt Kristensen AS
Main contractor: BRG Entreprenør AS
Project manager: Dag Terje Håland
Subcontrators: Rencon AS, Murermester Arnt Kristensen AS
Mapei coordinators: Trond Helgedagsrud and Alexander Kristensen, Mapei AS (Norway)
Photos: Tomasz Majewski Photography, Trond Helgedagsrud
MAPEI products
Smoothing and repairing concrete: Conplan Eco F*, Confix*, Confix Fin*, Mapeprimer M*, Redirep 45 RSF*, Planitop Fine Finish,
Admixture for mortars: Superflyt*
Structural anchors: Mapepoxy BI*, Mapepoxy L*, Mapepoxy LR*, Nonset 400*;
Anchoring: Mapefix VE SF
Waterproofing: Resfoam 1KM, Mapecoat CFS*, Resfoam 1KM AKS*
Installing ceramic tiles: Ultrabond MS Rapid
*These products are manufactured and distributed on the Norwegian market by Mapei AS (Norway).
