Passive House & Step 5

Step 5 of the BC Energy Step Code requires roughly a 60% improvement over baseline thermal energy demand and an airtightness target of 1.0 air changes per hour at 50 pascals (ACH₅₀) for detached homes — a meaningful jump from Step 3, which most Burnaby builds default to. Passive House goes further: 0.6 ACH₅₀, plus per-square-metre energy demand caps. We walk you through which target makes sense for your project, your lot orientation, and your long-term goals before locking in the energy modelling.

Hitting Step 5 on a Burnaby lot generally means continuous exterior insulation — typically 4 to 6 inches of mineral wool or rigid foam outboard of the sheathing — combined with dense-pack cellulose or batt in the cavities. Effective R-values land around R-30 walls and R-50+ roofs, depending on the assembly. Triple-glazed windows with insulated frames, careful thermal-bridge detailing at slab edges and balconies, and sub-slab insulation under heated floors. The assemblies aren't exotic; the discipline is.

Airtightness is where most Step 5 builds either succeed or quietly fail. We detail a continuous air barrier — usually a self-adhered membrane or taped sheathing — and we run a midpoint blower-door test at insulation rough-in, before drywall closes the walls. Finding leaks at that stage is hours of work; finding them at final is days. The final test has to pass before occupancy, and we treat the midpoint number as the real deadline.

An airtight envelope changes how the house breathes. Heat-recovery ventilation (HRV) or energy-recovery ventilation (ERV) is mandatory at this performance level, sized and balanced room-by-room. For heating and cooling, we default to cold-climate air-source heat pumps — ducted or ductless depending on layout — with electric backup. The combustion appliances most older homes used (gas furnaces, gas water heaters) come out of the design entirely. Hot water is heat-pump as well.

A Step 5 home in Burnaby with too much south or west glazing will overheat in summer — the envelope is too good to dump the gain passively. We work with the architect on overhang depth, exterior shading, and glazing distribution so the home performs in August, not just February. On Capitol Hill or Westridge view lots this gets interesting; the view drives the glass and the glass drives the cooling load. The energy model surfaces the trade-off.

Step 5 requires a registered energy advisor running EnerGuide modelling and confirming the as-built numbers. Passive House certification requires PHPP modelling and third-party verification through the Passive House Institute or PHIUS. Both produce an as-built energy report that becomes part of your warranty package and your resale story. We run the modelling early, not as a permit-stage afterthought, because the assemblies and mechanical have to be designed against the model — not justified to it after the fact.