The Challenge

Opened in 2018 the Pálás arthouse cinema in the heart of Galway city is a landmark concrete building.

Overall winner, 38th annual Irish Concrete Society awards 2019

The structural form of the cinema was constructed in its entirety with reinforced concrete, from the foundation and basement, to the slabs, walls and columns and even the fireplace and chimney. As well as meeting structural and durability requirements the concrete was also to be exposed to meet the highest standards for visual concrete.

A fair faced visual concrete was specified in order to achieve the architectural features for both the internal and external finishes with special emphasis placed on the concrete mix design to achieve the following properties:

A light colour

Consistency of colour

Minimal blemishes

Durability

The Solution

Roadstone supplied a specially designed concrete mix that allowed for the concrete to be placed by pump while also ensuring that the proportions of the cements, aggregates and admixtures adhered to the project specification requirements. This mix ensured that the architectural features of the building such as the consistency of colour, the reduced instances of blemishes and the smooth lines of the different concrete elements such as the embossed PALAS lettering on the exterior of the building were achieved.

In addition to being architecturally stunning, this concrete building must also be serviceable, meeting both structural and durability requirements. Located near to the Claddagh basin, the cinema is exposed to airborne chlorides from sea water which can ingress through concrete to corrode the steel reinforcement. The concrete supplied by Roadstone was produced to I.S. EN 206:2013 and meets the requirements of the project specification including the concrete requirements for the exposure conditions.

The Result

Each pour of fair faced concrete was supplied from Roadstones production plant in Two-Mile-Ditch on the east side of Galway city. Supplying from one production plant ensured a consistency of concrete colour for the duration of the project. In addition, Roadstones quality team placed particular emphasis on the testing of the constituent materials and the concrete itself which further aided the goals of achieving a concrete with a consistency of colour and minimal blemishes.

Takeaways

While selection of a suitable concrete mix is important when looking to achieve a high-quality finish, of just as much importance is the preparation of concrete formwork and the placement and compaction methodology. Important criteria that should be considered prior to any fair faced concrete pour include:

The type of formwork

Grout-tight formwork joints

The release agent and its application

The method and rate of placement of the concrete

The suitability and consistency of the concrete mix

The compaction plan

The most suitable time at which to strike the formwork