Armstrong Step Code Requirements
Current Step: 3 | ACH Target: 2.5 ACH50 | Climate Zone: 5 | HDD: ~3,950 | Permit Office: cityofarmstrong.bc.ca | Adjacent Jurisdiction: Township of Spallumcheen
What’s required right now
Step 3 is mandatory for all new Part 9 residential builds in the City of Armstrong. The airtightness target is 2.5 ACH50, verified by blower door test before occupancy.
Armstrong sits in Climate Zone 5 with HDD around 3,950, similar to nearby Vernon and Lumby at the cold end of CZ5. The City has a population of roughly 5,500 and is geographically wrapped by the Township of Spallumcheen, which complicates which permit office applies to a given property.
Permit boundary: City vs Spallumcheen
Properties inside the City of Armstrong boundary are permitted by the City. Adjacent properties (most rural land surrounding Armstrong, including agricultural and rural-residential parcels) fall under the Township of Spallumcheen, which operates a separate building department.
Step Code requirements are identical between the two jurisdictions. The difference shows up in:
- Permit application portal and fee schedule
- Inspection scheduling (Spallumcheen uses RDNO contract inspectors for some scopes)
- Septic and well permit coordination (Spallumcheen rural lots add IHA review)
- Agricultural Land Reserve (ALR) constraints for many Spallumcheen lots
A property with an Armstrong mailing address may be in Spallumcheen. Verify with the BC Assessment property record before submitting your permit package.
Construction patterns in Armstrong
Armstrong’s residential building activity is more diverse than its small population suggests:
| Pattern | Step Code consideration |
|---|---|
| Single-family infill | Standard CZ5 build, R-22 + R-7.5 walls typical |
| Manufactured/modular on rural lots | Marriage joint between modules is a common air leakage point |
| Starter homes and ranchers | Rim joist + attic hatch are top failure points |
| Farm homes with outbuildings | Heated workshop sharing envelope adds air barrier complexity |
The geometry of most Armstrong builds is simpler than custom mountain homes, which makes air sealing more straightforward but no less essential. Even a 1,400 sq ft rancher has 30+ envelope penetrations (electrical service, plumbing stacks, exhaust ducts, dryer vent, recessed lights) that all need sealing to land 2.5 ACH50.
Common compliance gaps in Armstrong builds
After several years of Step 3 in the area, the recurring fail patterns are:
- Rim joist transitions. Spray foam stops short, gaps at corners. The single highest-frequency failure point
- Electrical panel penetration. Service entrance through exterior wall typically un-sealed
- Bathroom and dryer exhaust. Duct-to-wall seal often skipped or done with low-grade caulk
- Attached garage-to-house wall. Needs both fire and air barrier treatment; air seal is often missed
- Attic hatches. No gasket, no insulation, standard fail point
Builders running a pre-drywall blower door test catch these before drywall closes them in. See the air sealing checklist for the full pre-drywall sequence.
Modular and manufactured home considerations
Spallumcheen sees a higher proportion of modular and manufactured homes than most municipalities. The marriage joint where modules connect is one of the most common air leakage failure points in modular construction, accounting for 20 to 30% of total leakage on a typical install.
Specifying factory-applied marriage joint sealing (rather than relying on the on-site installer) substantially improves blower door results. For factory-built homes already on site, a post-installation aerosol air sealing pass closes both the marriage joint and the dozens of other small penetrations created during transport and set.
Permit process
- Pre-construction. Submit energy compliance report with permit application to the appropriate jurisdiction (City or Spallumcheen). Allow 3 to 5 weeks for permit issuance
- Mid-construction (optional). No municipal blower door rebate; pre-drywall testing still pays off
- As-built. Final blower door test plus updated compliance report before occupancy
Rebate stack for Armstrong projects
| Source | Amount | Notes |
|---|---|---|
| FortisBC New Home Program | $9,000 to $15,000 | Step 4 with hybrid heat pump |
| FortisBC New Home Program | $11,000 to $20,000 | Step 5 with hybrid heat pump |
| CleanBC Better Homes | $4,000 to $10,000 | Heat pump rebate, stacks |
| Greener Homes Loan | up to $40,000 | Interest-free for energy upgrades |
Armstrong is in FortisBC natural gas service area where infrastructure exists. Many rural Spallumcheen properties use propane or electric. Step Code requirements are the same regardless of fuel; rebate eligibility differs by program. See the Step Code rebates guide for stacking rules.
What’s coming in 2027
Step 4 is expected provincially in January 2027 at 1.5 ACH50. For Armstrong’s typically straightforward residential builds, Step 4 is achievable but tight. Most builders targeting 1.5 ACH50 reliably are using aerosol air sealing rather than relying on manual sealing alone, particularly for modular or owner-builder projects where air sealing skill varies.
Nearby communities
Builders working Armstrong often also serve:
- Vernon, 20 minutes south, North Okanagan hub
- Coldstream, south-east of Vernon
- Lumby, east through the Coldstream Valley
- Enderby, 15 minutes north along Highway 97A
All share CZ5 Step 3 requirements with the same 2.5 ACH50 target.
Next steps for your Armstrong project
- Confirm City vs Spallumcheen jurisdiction before permit submission
- Run the rebate calculator for project-specific numbers
- Compare air sealing methods for the build type you’re working with