Attic insulation upgrade in our Guelph home — from R-20 to R-60, gas bill before and after

We bought our 1985 Guelph bungalow knowing the attic insulation was original R-20 fibreglass batts. Got the EnerGuide evaluation done first, then upgraded. Sharing the real numbers.

Pre-upgrade EnerGuide evaluation:

  • Energy Advisor assessment: $400
  • Result: attic insulation rated as priority #1 upgrade
  • Estimated annual savings from R-60 upgrade: $680/year

The upgrade:

  • 1,250 sq ft attic
  • Air sealing first (polyurethane foam at all penetrations, pot lights, etc.) — this was 2 hours of the work
  • Blown cellulose to R-60
  • Baffles maintained at eaves for ventilation

Cost:

  • Insulation contractor (air sealing + blown cellulose): $2,850
  • No structural work needed

Grants received:

  • Canada Greener Homes Grant: $600 (R-60 upgrade qualifies)
  • Enbridge rebate: $400
  • Total grants: $1,000

Net cost: $1,850

Gas bill comparison:

  • Jan 2024 (before upgrade): $287
  • Jan 2025 (after upgrade): $196
  • Dec 2023 (before): $242
  • Dec 2024 (after): $171

Monthly savings: averaging $78/month in heating season. Payback on net cost: under 2 years.

My recommendation:
Get the EnerGuide evaluation first ($400). The energy advisor identifies your actual priority upgrades — don’t guess. In our case, air sealing at the attic floor was half the value; the blown cellulose was the other half. Skipping the air sealing step would have cut the results significantly.