The buildings sector figures prominently in the U.S. government’s ambitious new greenhouse gas reduction commitment, submitted to the United Nations (UN) last week. That pledge to cut nationwide emissions 26 to 28 per cent below 2005 levels by 2025 will necessitate an approximate doubling of the current rate of progress.

In outlining its Intended Nationally Determined Contribution (INDC), the U.S. has joined the European Union (EU) and five other countries in preparation for the December 2015 climate change conference in Paris and an anticipated new international agreement on greenhouse gas (GHG) reduction targets for the 2021-2030 period. Canada is not among the keeners, but UN officials express optimism that more of the 196 parties to the UN Framework Convention on Climate Change (UNFCCC) will follow suit even if they’ve missed the preferred March 31 deadline — endorsed at last year’s UN climate change conference in Lima, Peru — for doing so.

“Over the coming months we expect many more nations to come forward to make their submissions public,” Christiana Figueres, the UNFCCC’s executive secretary, stated in a March 31 media release. “The pace at which these contributions are coming forward bodes well for Paris and beyond.”

Although climate change concern tends to focus on carbon dioxide (CO₂), GHGs encompass, and the UNFCCC addresses, a wider scope of damaging gases. These include methane, hydrofluorocarbons (HFCs), nitrous oxide, perfluorocarbons, sulphur hexafluoride and nitrogen trifluoride.

The buildings sector primarily releases CO₂, directly through the combustion of fossil fuels for heating and domestic hot water and indirectly through demand for fossil-fuel-fired sources of electricity, but buildings are also significant users of HFCs in refrigerants and foam insulation. Meanwhile, building occupants generate a landfilled waste stream that contributes to methane, which has a global warming potential (GWP) more than 20 times greater than CO₂ over a 100-year time span.

As the label suggests, INDCs are self-imposed objectives for UNFCCC participants with the key qualifier that they cannot roll back earlier promises and must aim for more aggressive targets than those set for the period ending in 2020. Notably, the U.S. is currently pursuing reductions equivalent to 17 per cent below 2005 emission levels. (This is also Canada’s target to 2020.)

“Achieving the 2025 target will require a further emission reduction of 9 to 11 per cent beyond our 2020 target compared to the 2005 baseline and a substantial acceleration of the 2005-2020 annual pace of reduction,” the U.S. INDC submission states. “The target reflects a planning process that examined opportunities under existing regulatory authorities to reduce emissions in 2025 of all greenhouse gases from all sources in every economic sector.”

In relation to the buildings sector, the U.S. lists upgraded building code requirements for commercial development, enhanced energy standards for 29 categories of appliances and equipment, and new allowances for low-GWP refrigerant among its recent regulatory initiatives to decrease GHG emissions over the long term. The government will also aim to cut GHG emissions in its federally owned/operated portfolio to 40 per cent below 2005 levels by 2025.

Pending regulations — often with implications for the buildings sector — are also identified. These include: added energy conservation standards; new building code requirements for residential development; regulations to cut pollution emissions from new and existing power plants; standards relating to methane emissions from landfills and the oil and gas sector; and limits on the use of HFCs.

The EU’s INDC sets a more aggressive GHG reduction target than the U.S. from a more advanced starting line. The 28 EU member nations have agreed to a binding target of a 40 per cent cut from 1990 levels by 2030.

The EU’s target to 2020 is a 20 per cent reduction from 1990 levels, while the new promise aligns with the Intergovernmental Panel on Climate Change (IPCC) philosophy that developed countries should carry a greater share of the obligation — collectively reducing emissions by 80 to 95 per cent of 1990 levels by 2050.

“Member states have already reduced their emissions by around 19 per cent on 1990 levels while GDP has grown by more than 44 per cent over the same time period,” the EU’s INDC submission notes. “Average per capita emissions across the EU and its member states have fallen from 12 tonnes CO₂-equivalent in 1990 to 9 tonnes CO₂-eq in 2012 and are projected to fall to around 6 tonnes CO₂-eq. in 2030.”

Other countries meeting the early suggested deadline to submit their INDCs include Gabon, Mexico, Norway, Russia and Switzerland. Of these, Mexico and Gabon gain attention as the first developing countries to state GHG reduction commitments.

The ‘no roll back’ criterion may be a factor in the missing submissions from developed nations. Several, including Canada, still have a large gap to bridge to reach the targets they’ve set for 2020.

“Globally we are not on track to stay under the internationally agreed upper limit of acceptable warming of 2 degrees Celsius above the pre-industrial level,” Halldor Thorgeirsson, the UNFCCC’s director for strategy, said in March 30 speech. “This is precisely why governments agreed in Durban in 2011 to negotiate the Paris Agreement and to join forces to close the pre-2020 emission gap through cooperative action.”

Barbara Carss is editor-in-chief of Building Strategies & Sustainability and Canadian Property Management.