Citibank Building, Custom House Quay - Scott Tallon Walker

The Citibank building is one of a series of blocks at the IFSC designed by Scott Tallon Walker, which includes Mayor House (occupied for the past year by the Bank of Ireland) and the A & L Goodbody building. The firm has also designed a hotel currently being built. The Citibank building is by far the largest of these developments; in scale, it is approximately half a million square metres and will hold over 2,000 office workers when completed in May. By comparison, A & L Goodbody's building accommodates around 400 staff.

One of the features shared by all these developments is the use of glass and Wicklow granite. Citibank's exterior incorporates panels of white, powder-coated aluminium, a material which demands regular attention if it is not to look dirty. In common with the A & L Goodbody block, the atrium is an important element in the Citibank design. Here, there are not one but three, with those at the west and east ends of the building rising to five storeys. Because of the demands for office space, the central atrium is two storeys high. The two large atriums act as reception/security areas and are not just topped but also fronted by glass - the east faces the river directly, the west is at an angle to it.

In both cases, the glass has been treated to ensure the interior does not become overheated; air-conditioning will also keep temperatures down.

Beyond security rises the main lift shaft, which is covered by more glass, this time frosted and further back again are the main staircases open to the space beyond.

At the west end of the building, this space is very substantial and takes in a public meeting area and coffee bar. Screens on the right hand side lead through to the main staff restaurant.

Moving towards the front of the building, a wide corridor runs from west to east by way of the central atrium which, despite its lower height, will be extensively planted like the other two. Since there are offices above this atrium, its glazed roof is to be artificially lit to give the impression of natural daylight. The other two atriums have been given a glazed, prismatic lightweight roof structure.

While the two wings of Citibank rise to five storeys, the central block has a sixth floor and, as in the A & L Goodbody building, it has a balcony to take in the impressive views available at this height. It also has brise-soleil screens set above windows to reduce glare. The combination of glass and pale-coloured stone and aluminium on the exterior helps to make what is a fairly massive structure look considerably lighter.