Did a full energy audit on our 1978 Mississauga home and ended up doing staged insulation upgrades over 18 months. Posting the full results.
The Audit (EnerGuide)
Our pre-retrofit EnerGuide score was 56. The auditor ranked our upgrades by ROI:
- Attic air sealing + insulation upgrade (highest ROI)
- Basement rim joist spray foam
- Main floor air sealing
- Main wall upgrade (lowest immediate ROI, most disruptive)
What We Did and What It Cost
Attic - $3,800
Existing blown fibreglass was R-22. Air sealed all penetrations (pot lights, plumbing stacks, top plates) then added blown cellulose to R-60. This was the best money we spent.
Basement rim joists - $1,100
2-inch closed-cell spray foam applied to all rim joist bays. Major reduction in cold floors and drafts.
Main floor air sealing - $650
Contractor sealed around all electrical outlets, switches, and penetrations with foam and acoustic sealant.
Total: $5,550
Results
Post-retrofit EnerGuide score: 71 (up from 56). Natural gas bills down approximately $780/year. Payback period roughly 7 years.
Greener Homes Grant
We received $2,600 back through the Canada Greener Homes Grant. Program availability changes so check nrcan.gc.ca. You MUST do the EnerGuide pre-assessment before work begins to qualify.
Key Takeaway
Do the attic first. The ROI is highest and the disruption is minimal compared to wall insulation.