Sustainability Series – 20 Kildare Street

Sustainability Series – 20 Kildare Street

Design, Repeat Commissions, Sustainability, Work

20 Kildare Street – A landmark office building for enhanced work life

The building is perfectly located at the epicentre of Dublin’s business and cultural life neighbouring well-known locations such as St. Stephen’s Green, The Shelbourne Hotel, Leinster House, Trinity College, Grafton Street and is within walking distance of the IFSC.

The development retained four existing Georgian buildings on Kildare Street. These are connected to a contemporary new office building by an impressive, glazed atrium which provides an attractive glazed link between the ground floor reception and the external courtyards.

The buildings on Kildare Street have retained their own entrances and can operate independently of the new building if necessary. The new building provides Grade A office accommodation of over 54,000sqft boasting LEED, WELL and NZEB certification. It also has the added certification of Wired Score Platinum.

20 Kildare Street is constructed in a well-established area of the city with numerous high profile tenants operating in this thriving business district. The site is well serviced from the Green Luas line, and bus services, Dublin bikes and DART.

The building consists of four period buildings which were treated sensitively throughout while achieving low energy performance. The modern building consists of eight levels including basement car park and amenities, ground floor reception and lounge and seven levels of premium office space. The offices area completed to full Category A standard with Four Pipe Fan Coil Units and LED lighting throughout.

The building is designed to cater for multi-let floor plates and is also suitable for a single occupier.

The building is served by best-in-class MRL elevators utilising destination control integrated with the building security systems and speed lanes.

20 Kildare Street was designed from the outset to achieve best in class in terms of sustainability and achieved LEED & WELL certification along with a BER A3 rating.

Energy Rating and Carbon Free

The BER of A3, fully NZEB compliant, with the buildings heating provided by renewable means, and from an active energy basis is 100% carbon-free.

Sustainability was at the forefront of the building design, and the targets in terms of Carbon Performance Coefficient (CPC), Energy Performance Coefficient (EPC), and Renewable Energy Ratio (RER) all outperform the reference building significantly

CPC: 0.92

EPC: 0.89

RER: 0.27

Sustainable design features


LED lighting is installed throughout the building. PIR occupancy sensors were incorporated in open plan areas to minimise energy use.  A lighting control system was installed to monitor and facilitate ease of control of the systems.

Energy consumption monitoring

Energy metering is installed on each floor distribution board, as part of the overall LEED strategy. This allows for monitoring of the overall usage through the central BMS system. Furthermore, all heating / cooling is sub-metered and linked to the BMS. Power factor correction was installed within the main switch room to further limit energy wastage.

Water consumption management and monitoring

Water meters have been added to each tenant floor plate. These are linked back to the central BMS.  They notify if high levels of water are being used, which may be caused by leaks in the system. Booster pumps have incorporated variable speed drives. All sanitaryware including WHBs, showers and toilets are low flow/flush, with taps being sensor-operated.

Heating and cooling

The high-efficiency 4-pipe heat pumps provide heating and cooling to tenant and landlord spaces.  All tenant spaces are provided with energy metering linked to central BMS. The office and toilet AHUs have heat recovery incorporated within each unit to ensure maximum efficiency. All ductwork associated with heat recovery plant is thermally insulated.  All domestic hot water is produced by Air Source Heat Pumps.


The energy contribution from the heat pumps and photovoltaics is renewable energy, this equates to 22 kWh/m²/year of primary energy being provided on site, approximately 27% of total primary energy come from renewable onsite.

Summary of sustainable features

  • High-performance construction envelope including low u-value and g-value
  • Air tightness construction
  • Multi-purpose unit (4-pipe heat pump technology) for heating and cooling
  • Air source heat pump for hot water system
  • PV array at roof level
  • Heat Recovery mechanical ventilation
  • Low specific fan power installed unit
  • Low installed lighting power & intelligent lighting control
  • VSD’s on pumps / fans

The sustainable design of the development presented an opportunity to ensure the overall building performs efficiently and meets the NZEB challenges. The entire building was dynamically modelled with the sustainable inputs, and the analysis and the calculation of the building performance metrics to show compliance with the Part L and BER. The façade was carefully considered to reduce cooling loads while allowing sufficient light transmittance.


The building sustainable objectives have been measured through the LEED & WELL assessment processes during the design and construction. The development achieved a LEED Gold rating, WELL certification and Wired Score Platinum.