Step Code Requirements:
Step 3
Need to meet Step 3 of BC's Step Code? We've got you covered.
Overview
Step Code has 3 requirement categories:
-
Air tightness score
-
Equipment score
-
Envelope 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
-
Envelope: TEDI
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.
GHG & GHGI (Greenhouse Gas & Greenhouse Gas Intensity): measures the greenhouse gas emissions associated with a building's energy use, over the course of a year. These metrics are used to determine compliance with BC's Zero Carbon Step Code.
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
Air Tightness
-
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
Envelope
Equipment
-
Heating: nat. gas furnace, condensing, AFUE 95.0%
-
Hot water: nat. gas instantaneous, condensing, EF 0.95