Squamish Step Code Requirements

Current Step: 3 | ACH Target: 2.5 ACH50 | Climate Zone: 4 | HDD: ~3,200 | Permit Office: squamish.ca/building

Current Requirements

The District of Squamish requires Step 3 for all new Part 9 residential buildings in accordance with the provincial mandate. As a community with a strong environmental focus, Squamish has supported progressive energy policy and may adopt higher requirements ahead of the provincial timeline.

Squamish is growing rapidly, with significant residential development driven by its position between Vancouver and Whistler along the Sea-to-Sky corridor. This growth means a steady stream of new construction projects going through the Step Code compliance process, and the District of Squamish Building Department handles energy compliance review as part of the standard permit application.

Climate Context: Mountain-Influenced CZ4

Squamish sits in Climate Zone 4 but with approximately 3,200 heating degree days, which is higher than typical coastal CZ4 locations like Vancouver (HDD ~2,825) or Victoria (HDD ~2,600). The proximity to the Coast Mountains means colder winter temperatures and more heating demand than a purely coastal location.

This has practical implications for builders:

Slightly higher insulation requirements than lower-HDD CZ4 cities, though still well within standard 2x6 wall capability
Energy models run warmer than Interior cities like Kelowna (HDD ~3,715) but cooler than the coast, putting Squamish in a middle ground
Wind exposure matters: The Sea-to-Sky corridor funnels wind, which increases infiltration pressure on buildings and makes air sealing even more important
Moisture load is significant: Coastal rain combined with mountain weather patterns means wall assemblies need robust rain screening and vapor management

Despite the higher HDDs, Squamish’s CZ4 designation means compliance targets are the same as Vancouver or Victoria. The slightly colder climate just means less margin for error in the energy model.

Air Sealing in Squamish’s Climate

Air sealing is the key lever for hitting the 2.5 ACH50 target, and Squamish’s wind exposure makes it even more critical. Buildings in the Sea-to-Sky corridor face higher wind-driven pressure differentials, which means any gap in the air barrier will leak more than the same gap in a sheltered coastal location.

Priority areas for Squamish builders:

Sill plate and foundation connections: Wind-driven air infiltration at grade level is a common failure point
Rim joist and band joist assemblies: These must be sealed completely, not just insulated
Penetrations through the envelope: Every pipe, wire, and duct needs individual sealing
Window and door installations: Proper flashing and air sealing at rough openings is critical in a wind-exposed, rain-heavy climate
Roof-to-wall transitions: Complex roof lines common in Squamish custom homes create multiple air leakage paths

A pre-drywall air sealing test is strongly recommended. Detailed sealing strategies are covered in our air sealing methods guide.

Permit Process

The District of Squamish follows the standard BC framework:

Pre-construction: Energy advisor models the design using appropriate weather data and produces a Section 9B compliance report
Permit application: Submit the energy compliance report with your building permit application to the District of Squamish Building Department
Mid-construction: Optional pre-drywall blower door test (recommended given Squamish’s wind exposure)
As-built: Final blower door test at 2.5 ACH50 and as-built compliance report required for occupancy

Rebates and Incentives

Squamish is served by BC Hydro for electricity and FortisBC for natural gas:

FortisBC: Up to $9,000 at Step 3, $15,000 at Step 4, and $20,000 at Step 5 through the hybrid heat pump pathway (full guide)
BC Hydro New Construction: Incentives for high-performance all-electric homes
CleanBC Better Homes: Provincial and federal incentives that stack with utility programs

The rebate math is particularly compelling in Squamish, where construction costs are already high. Incremental spending on air sealing and insulation to reach Step 4 can be partially offset by FortisBC rebates of $15,000 per unit. Use our rebate calculator to estimate numbers for your Squamish project.

Looking Ahead: Step 4

Step 4 is expected province-wide in 2027. For Squamish builders, the airtightness target will drop from 2.5 to 1.5 ACH50. With Squamish’s higher HDDs and wind exposure, achieving 1.5 ACH50 requires disciplined air sealing from the framing stage onward.

The insulation upgrades for Step 4 at CZ4 are manageable. The real challenge is the airtightness target. Builders who develop strong air sealing practices now will find the transition to Step 4 straightforward, while those relying on marginal passes at 2.5 ACH50 will struggle with 1.5.

What Builders Should Do Now

Account for wind exposure in your air sealing strategy, as Squamish’s Sea-to-Sky location increases infiltration pressure on the building envelope
Run a pre-drywall blower door test on your next project to benchmark your current air sealing performance
Target Step 4 on at least one build to practice hitting 1.5 ACH50 and access higher FortisBC rebates
Invest in crew training on air sealing methods, focusing on the transition details and penetrations that cause most failures
Contact the District of Squamish Building Department early to confirm current requirements and discuss any planned bylaw updates