This paper examines the opportunities for, and impacts of, potential energy performance and emission reduction standards for existing buildings in the Province of British Columbia. It includes evaluation of three standards -- ASHRAE 100-2015, ASHRAE 90.1-2010, National Energy Code of Canada for Buildings-2015 -- and retro-commissioning procedures. Standards are assumed to apply to the existing building stock, except low-rise residential buildings, at the time of existing building alterations.

The study considered recent building permit statistics across the province and a survey of local enforcement authorities regarding energy-related construction permit applications, major building systems being affected, and current code enforcement practices. About one-third of all permit applications provide an opportunity for applying new energy standards to existing buildings. The energy savings and greenhouse gas emissions reductions resulting from the aforementioned standards were estimated for specific energy systems within each of eight building archetypes. A benefit-cost analysis was conducted that considered incremental capital costs and energy cost savings beyond current practices to estimate the net present value of energy benefits.

A 30-year roadmap is presented with two implementation scenarios. The cumulative annual energy savings and emissions reductions for each roadmap scenario is presented for the period from 2016 to 2030. The results illustrate potential greenhouse gas emissions reductions of approximately 0.5 metric megatonnes per year in 2030. Natural gas savings can be maximized under that same scenario with 7.9 million gigajoules per year in 2030. Electricity savings can be maximized under a hybrid of ASHRAE 90.1-2010 for small-scale building permits and ASHRAE 100-2015 for large-scale building permits, saving 7,400 GWh/yr in 2030.