F280 Heat Loss / Heat Gain Calculation

The Right Size Heat Pump Changes Everything.

Most HVAC systems in Canada are improperly sized because the industry relies on experience and approximation instead of engineering. We bring certified, calculation-based sizing to every project using the CSA F280-12 standard.

Mitsubishi Electric heat pump installation by Alpine Home Energy
CSA F280-12 Certified BC Building Code Referenced

What is CSA F280-12?

Canada's Standard for Residential HVAC Load Calculations

CSA F280-12, Determining the Required Capacity of Residential Space Heating and Cooling Appliances, is the Canadian Standards Association standard for calculating the precise heating and cooling loads of a home. It is referenced in the BC Building Code and is the only method recognized for compliance-based residential HVAC design in British Columbia.

Unlike simplified "rule of thumb" estimates (e.g. BTU per square foot), F280-12 accounts for the actual thermal characteristics of the building envelope and local climate data.

What does the calculation account for?

Building Envelope Geometry
Floor area, ceiling heights, and volume of each conditioned space.
Insulation Values (RSI)
Actual R-values of walls, roofs, floors & slabs — not assumed values.
Window & Door (USI)
U-values, SHGC, area, and orientation of every glazed assembly.
Internal Heat Gains
Occupancy, lighting, and appliance loads that offset heating demand.
Air Infiltration & Ventilation
ACH rates, HRV/ERV specs, and intentional ventilation loads.
Solar Heat Gain
Passive solar contributions by orientation — matters in BC's climate.
Duct Losses
Heat loss through ducts in unconditioned spaces.

Downsides of Getting It Wrong

Improperly sized equipment costs more upfront, runs inefficiently, and fails prematurely. The consequences of both oversizing and undersizing are significant.

⬆ Oversized System

  • Short-cycles on and off, never reaching steady-state efficiency
  • Poor humidity control & clammy summers
  • Excessive wear on compressor and heat exchanger
  • Uneven temperatures between zones
  • Higher upfront cost for unnecessary capacity

⬇ Undersized System

  • Cannot maintain design temperatures on peak days
  • Runs continuously at full capacity — high energy bills
  • Premature equipment failure from constant overloading
  • Comfort complaints and callbacks for contractors
🌡️

Comfort

No hot or cold spots. Consistent temperature in every room, every season.

Efficiency

Right-sized equipment runs at peak efficiency — lower bills, smaller carbon footprint.

🔧

Longevity

Equipment that isn't over- or under-worked lasts significantly longer.


Why Contractors Choose Alpine Home Energy

Running a tight operation means delivering installs that work first time, every time. A CSA F280-12 heat loss and heat gain calculation gives you the engineering foundation to do exactly that — before any equipment is ordered.

1
Take the guesswork out of equipment selection

F280-12 gives you a defensible, code-referenced number to work from.

2
Protect yourself on complex jobs

On high-performance builds, renovations with upgraded envelopes, or homes going all-electric, a proper load calculation documents that you specified the right equipment. Professional cover if questions come up later.

3
Satisfy permit requirements with confidence

Many municipalities in BC are tightening mechanical permit requirements. An F280-12 report in your submittal package keeps inspections smooth and projects on schedule.

4
Offer clients something most installers don't

Pairing your install with a certified load calculation is a differentiator. It shows your clients you're thorough, professional, and invested in a result that actually performs.

5
Works around your timeline

Send us the plans and specs — we handle the calculation and deliver a full report typically within 2–3 business days, so it fits your workflow without slowing down the project.


Our Process

Five clear steps from information gathering to final report delivery — typically completed in 2–3 business days.

1
Information Gathering

Architectural drawings, envelope specs, window schedules, mechanical systems & blower door results.

2
Load Calculation

CSA F280-12 methodology — peak heating and cooling loads for whole building and each zone.

3
Equipment Recommendations

Appropriately sized heat pump models, furnaces, and air handlers based on calculated loads.

4
Report Delivery

Complete, stamped F280-12 PDF report — ready for contractor, AHJ, or homeowner.

5
Support & Follow-Up

Available to answer questions from your mechanical contractor or AHJ throughout the project.

Free Resource: The Right Size Heat Pump Changes Everything

Download our complete guide to understanding CSA F280-12 heat loss and heat gain calculations. Written by Allen Joshua, CEA, CPHC, NZEA — free for homeowners and contractors.

Download Free PDF Guide

No email required · Instant download · 3 pages

Ready to get your F280-12 report?

Free consultation included. Whether you're a homeowner planning a heating upgrade or a contractor who needs accurate load calculations — we've got you covered. Reports delivered within 2–3 business days.