Step Code has 3 requirement categories:
Air tightness score
For a house to pass Step 3, it must meet at least one metric in all three categories. For more about the numbers involved, see metrics.
Step Code is a performance code, meaning there are many ways to meet the targets.
For specific ideas for assemblies and equipment, see our Step 3 Sample Home.
For more information on Step Code's design flexibility, visit our Learning Centre.
Step Code Metrics
BC Step Code metrics can be divided into 3 areas:
Air tightness: ACH₅₀
Equipment: Reference House and MEUI
ACH₅₀ (Air changes per-hour at 50 Pa) is a measure of a home's air tightness. ACH is tested with a blower-door for Step Code compliance. ACH₅₀ requirements vary only by step level.
ERS ref. House measures envelope and equipment efficiency. When a proposed house is modeled, is it compared with a twin version of itself, built according to the 2018 code. The difference in efficiency is used for Step Code compliance. ERS ref. House requirements vary only by step level.
MEUI (Mechanical Energy Use Intensity) measures envelope and equipment efficiency. It is based on how much annual energy input is required to condition the home. MEUI requirements vary by climate zone and floor area, as well as step level.
TEDI (Thermal Energy Demand Intensity) is a measure of envelope efficiency. It is based on how much annual energy output is required to condition the home. TEDI requirements vary by climate zone, as well as step level.
For more information about MEUI and TEDI requirements for your project, see the BC Climate Map and Section 9.36 of the BC Building Code, or contact us for a free consultation with a certified Step Code advisor.
Step 3 Sample House
Continuous air barrier
High level of care with air sealing details
Walls: 2x6, R22 batt insulation
Windows: double glazed, USI 1.4, SHGC 0.3
Ceilings: R40 batt insulation
Heating: nat. gas furnace, condensing, AFUE 95.0%
Hot water: nat. gas instantaneous, condensing, EF 0.95