In 2015, Careys Civil Engineering began work as specialist concrete subcontractor to Robertson Construction delivering a new distillery for the nearly 200-year old Macallan whisky brand. The atmospheric new distillery located on the Easter Elchies estate on the River Spey aims to create a world-class distillery and inspirational visitor experience at the heart of the Macallan.
As the project was positioned in a Site of Special Scientific Interest (SSSI) on the River Spey, our team worked collaboratively with all stakeholders on the project to minimise the environmental impact of our works on the area, as well as ensure that we respected and enhanced the natural environment. To ensure we delivered our client’s vision of delivering a sympathetic and complementary addition to the local landscape, we developed a bespoke Environmental Management Plan at during pre-construction planning to carefully stockpile and reuse material excavated from the site, eliminating the requirement to import material and reducing the negative environmental impact of our work. Our extensive pre-construction planning also included the development of a phasing strategy for our specialist concrete works which would enable the safe installation of the unique distillery equipment and access to the complex roof structure.
The unique design of the distillery and visitor centre included a combination of reinforced concrete and a structural steel frame that supported a timber roof. As part of the works we carried out construction of the basement slab and underslab drainage, a 12m high retaining wall, and installed waterproofing to the structure.
Our team formed a series of concrete cores to bear the weight of the roof structure whilst ensuring sufficient operational space within the distillery structure. This was achieved through excavation of the hillside which we then lined with reinforced concrete retaining walls. The roof was supported by a series of octagonal steel frames which acted as ring beams for the domes and were supported by the concrete superstructure. We worked in close collaboration with the roofing contractor throughout the assembly of complex roof structure ensuring the Macallan brand vision became reality.
To achieve the exposed, architectural quality concrete specified by the client, our team collaborated with the project architect to ensure we used the correct mix, pour and protection methodology at all times. Our expertise working with bespoke concrete mixes enabled us to identify that the specified concrete mix required wider consultation with our in-house designers and supply chain to develop a new mix design which reduced the risk of thermal and dry shrinkage cracking. In developing the correct mix, we trialled multiple options including pigmented concrete, a pulverised fly ash blend, and a waterproofed/reduced efflorescence mixture. After these samples had been inspected, the architect chose to use the pulverised fly ash with waterproofing mixture for all exposed concrete elements on the project.
Our samples demonstrated the use of a mortar mix to fill boltholes had the potential for visual irregularities. We designed bespoke moulds to form concrete plugs to infill the boltholes using the main concrete mix. These plugs were installed 5mm below the wall surface, fitting perfectly within the bolt holes in the wall, successfully meeting the visual standards of our client and creating a unique design feature.
The mash tun structure within the distillery was formed from reinforced concrete 3m high, 15m radius. The exposed walls were finished to an architectural standard, with exact tolerances on both the express joints and bolt hole layout. We poured the wall in six separate pours, achieving a high-quality finish with millimetre-accurate geometry.
The first exposed retaining wall stretched up to 12 metres high and included 300mm wide pilaster detail running the full height of the wall. The retaining wall was poured in three lifts. Our experienced team remained vigilant throughout the works to ensure accurate verticality of the pilasters which formed a design feature within the finished structure.
We subsequently constructed a nine metre-high, 300mm thick wall which ran for over 300 metres on a heavily reinforced base. To build this, we poured the concrete using a tremie pipe in layers to suit the rate of rise, achieving an outstanding finish with little to no loss of grout, segregation or honeycombing.
A major challenge of the specialist concrete works lay in achieving the required consistency of colour over such a vast area of concrete, especially considering the extreme variance in the weather over the winter months in this remote location. After consultation with our concrete supplier, we took the decision to use heated water through the winter and keep concrete slumps within tight margins to protect against the risk of colour variance. In addition to this, our team protected all rebar and formwork from the elements both before and after concrete pours, resulting in a consistent colour and high standard of concrete finish.
The promontory structures were also a major feature of the internal building, consisting of 1m diameter columns measuring approximately 4.5m high, with fin walls positioned between these and a suspended slab with featured slab edging and upstands.
The Cave Privée, within the Visitor Centre, was a key part of the architect’s vision, designed to be the focal point of a visitor’s experience. The area consisted of double height feature walls, 300mm diameter circular columns, a curved, splayed slab edge and multiple curved, radial downstand beams with a patterned layout throughout the soffits. In addition to installing this striking feature, we also installed an in-situ stair and ramp, which we constructed to the highest quality to meet the architect’s exacting visual standards. This unique project provides an unforgettable visitor experience and serves as a visual benchmark that demonstrates the outstanding quality of the Macallan brand and will stand testament to our expertise in the delivery of bespoke architectural concrete.