In 2003 Dublin City Council launched a design competition to secure a joint venture partnership that would build social and affordable housing on a 4 hectare council owned site to the west of the city. The brief required the design of innovative high density, own door, family housing with surface parking and quality amenity spaces throughout. The housing would be economical to build but use innovative modern methods of construction to ensure speedy erection and ensure quality dwellings.
The competition was won by O’Mahony Pike, in collaboration with Park Developments and John Sisk and Sons.
The development became known as Cedar Brook and on completion included 376 duplex units, apartments and family houses achieving a density of 94 units per hectare. The triangular site dictated a solution that included 4 storey terraces, addressing the perimeter boundries and reducing in scale to 3 and 2 storey blocks approaching the centre of the site where a creche and a park were located. The 4 storey terraces are designed to replicate a traditional Victorian Dublin model with repeating bays of 6 own door apartments and duplex units, each served by a single external stairway with small feature apartment buildings bookending each terrace.
The 3 story terraces have a traditional house at ground and first floor with an apartment at third floor accessed via a feature staircase. Over 200 dwellings have private rear gardens with the balance provided by large terraced balconies.
Innovative techniques and practices were deployed on the project which ensured that the scheme was delivered to a programme that was 35% quicker than traditional building methods and at no additional cost. All parties realised that this was the first development of its kind in Ireland. High density and low costs are not negative descriptions, when this social housing scheme is considered. The interplay of levels, which this scheme exploits, provides a new model where privacy and space can be enjoyed by all. What was produced, has been proven to be one of Dublin‘s most successful developments, offering spacious, bright, high quality and affordable housing in an attractive environment.
The result has been a highly successful development in regards to time, cost, quality and safety. A number of different building products and materials were chosen, although they were not revolutionary in their own right, pooled together they reinforced the new model of cooperation and innovative thinking that marked out the project at its outset.
Amongst these, the use of hot dip galvanized steel throughout the development stands out as a very significant feature. It works on many levels, not all of which are immediately obvious but all of which contribute hugely to the ongoing success of the development.
The many benefits of galvanizing were well aligned to the objectives of the project. A critical first consideration was ensuring fast construction. One of the advantages of hot dip galvanizing is the speed at which it can be processed – in a factory controlled environment – ensuring the steel arrives on site complete and ready for erection with no further finishing required. Inherent to the coating characteristics is its zinc-alloy layers that afford a tough abrasion resistant coating that can easily deal with onsite handling and erection.
Another important design criteria for the project was creating housing that would be there for the long term without incurring unnecessary maintenance costs. The projected life of 50 plus years for galvanizing gave the designers the added confidence in specifying galvanizing for this innovative project.
Revisiting Cedar Brook – 14 years on
A recent visit to Cedar Brook proves the veracity of the decisions made by the design team in 2003. The estate is now a quiet tranquil enclave of mature trees and shrubs. General coating thickness measurements on the galvanized steel elements reveals some interesting results. Some of the lighter box section steel, still show a minimum of a 60 μm coating, while the main frames forming the staircases show minimum coating thicknesses of over 100 μm. This indicates that the hot dip galvanized steelwork will probably exceed a 50 year maintenance free performance.
Not only has the process contributed to the initial fast construction complication objectives of the project, the coating continues to contribute towards its sustainable credentials.
Architect: O‘Mahony Pike
Image: Jerry O‘Leary Photography, Galco Steel Ltd