Technologies & Techniques

Navan Credit Union: energy efficient building
Courtesy of Comhar SDC

Some of the technologies and techniques used in the building include:

• The building is heated passively through use of orientation, shading, and percentage aperture for different elevations. These factors were taken into consideration from the beginning and are crucial to the holistic methodology used. The resulting building is able to take advantage of solar gains and shading without over-heating or being too cool. Deciduous plants ensure maximised daylight in winter.

• Solar Water Heating is utilised and any excess goes into the space heating system.

• High efficiency gas-fired heat pumps are used in the strategic auxiliary cooling system.

• The heating system is in a banked series of modulating condensing boilers, which are efficient whatever the load, to take full advantage of the load/ efficiency curve.

• Photovoltaic panels which are coupled into low energy fans, actuators, dampers and vent controls, significantly reduce the demand on the grid supply, which is by Airtricity only.

• The Building Management System works from a station that is free and clear of all turbulence and disturbance. It measures the wind direction and force, shade temperature, humidity and this informs the programmable controller of the whole system.

• The building is naturally lit as much as possible.

• The ventilation system works through passing air through the cool undercroft (a concrete slab made using Ecocem’s environmentally-friendly cement) which can heat the air in the winter and cool it in the summer. There is also a solar chimney which creates a natural updraft (which provides 1 cubic meter per second of free air). Another non mechanical air conditioning system, the Venturi, gives 7 cubic meters per second of free air.

• A peace garden was built around the building which gives natural shading.

• SUDS (sustainable drainage systems) has been utilised for all the roads, paths and paving.

This project has used science know-how and supply-side expertise to create an interesting, functional and sustainable building. Testament to its innovation is the fact that it has been included as case study in a book evaluating some of the most cuttingedge, sustainable buildings in the world.