Investment of €30m sees 1 Cumberland Place cut energy use by 63%

Ber rating of X’s European headquarter office jumps from E2 to B2 following works by Hibernia Reit and Hibernia Real Estate Group

The former Cumberland House in Dublin city centre has moved into the top 5 per cent of Ireland’s most energy-efficient office buildings following the completion of €30 million in improvement works.

The investment by Hibernia Reit and its new owner, Hibernia Real Estate Group, works out an average cost of just €233 per sq ft, and has brought the Ber rating of the 11,984 sq m (129,000 sq ft) property, now known as 1 Cumberland Place, from a lowly E2 to a more sustainable and investor-friendly B2 and has seen a 63 per cent reduction in the building’s rated primary energy demand.

Developed originally in the 1970s, the former Cumberland House was acquired by the then Hibernia Reit for €51 million in 2015. With the then vacant property extending to a total area of 10,405 sq m (112,000 sq ft), the price paid equated to a capital value of about €455 per sq ft.

At the time of its purchase, Hibernia Reit said the property had significant redevelopment potential with existing planning permission to replace it with up to 23,225 sq m (250,000 sq ft) of new office accommodation. With the focus of investors and occupiers now firmly fixed on meeting their ESG (environmental, social and governance) targets, that plan has given way, for now at least, to improving the existing structure’s sustainability.


While 1 Cumberland Place is fully let to X, the platform formerly known as Twitter, and Travelport, much of the building’s space is set to be occupied from next year by TikTok. The Chinese-owned social media platform has agreed a deal to sublet four of the seven-storey property’s five floors from X for up to five years.

Hibernia Real Estate Group recently commissioned a report from RKD Architects with a view to documenting the process of decarbonising 1 Cumberland Place. Outside of the immediate improvement in its Ber rating, the report found there has been a 39 per cent improvement in efficiency realised due to the installation of energy-reduction and heat-recycling technology over the last two years.

The report says the building’s measured performance is now even better than that captured by its Ber rating. With much of 1 Cumberland Place’s original structure and skin retained rather than replaced, the report estimates that its embodied carbon footprint is 66 per cent lower than that of a newly constructed building.

Heat-recovery ventilation, LED lighting and power-factor correction had all been applied by Hibernia Reit during its ownership, leading to the building achieving a B2 Ber rating and LEED (Leadership in Energy and Environmental Design) Platinum certification in May 2017.

In 2021, Hibernia Real Estate Group began making additional improvements. A new energy data management system was supplied by Wicklow-based CoolPlanet, making it easier to track and understand 1 Cumberland Place’s decarbonisation metrics including energy, water, waste, and Scope 1, 2 & 3 emission levels. Hibernia then invested in new demand-control ventilation technology supplied by Dublin-based Symphony Energy.

Symphony’s system uses a combination of sensors and software to optimise heating and cooling based on real-time demand. It also allows for the recycling of waste heat into usable heat while generating free cooling for the building.

RKD’s report shows that following the introduction of these additional measures, primary energy demand in 1 Cumberland Place has reduced from 337 kWh/m2 in 2018 to 208 kWh/m2 in 2022, a drop of 38 per cent and the building’s energy use intensity has reduced from 205 kWh/m2 in 2018 to 125 kWh/m2 in 2022, a drop of 39 per cent.

Dr Richard O’Hegarty, research lead at RKD’s research division says: “1 Cumberland Place is an example of how Ireland’s built environment can carve out a pathway to net zero. This is a positive story that should encourage similar action nationally and elsewhere. If it is used as an exemplar, it is important to note that achieving such results requires a hands-on approach to building monitoring, management, and improvement.”

Ronald Quinlan

Ronald Quinlan

Ronald Quinlan is Property Editor of The Irish Times