Free Builder’s Unit Converter
Convert Imperial / Metric, RSI / R-value / U-value, Btu/h / kW, CFM / L/s, Temperature, roof slope and more with our free unit converter tool. Essential for builders and homeowners.
Quick Reference Guide
RSI to R-Value
(typical wall insulation)
(better wall insulation)
(typical attic insulation)
(Step Code attic insulation)
U-Value (W/m2K) to R-Value
U-value (the rate of heat loss for windows) is different than R-value (a wall’s rate of heat loss resistance)
Common Energy Units
Understanding Energy Efficiency Units
RSI vs R-Value
Canada uses RSI (thermal resistance in metric), while the US uses R-value (thermal resistance in imperial). Building codes, manufacturers, and contractors use both systems, making conversion essential.
ACH50 (Air Changes per Hour)
Measures how many times the total volume of air in a building is replaced per hour when the building is depressurized to 50 Pascals. Lower numbers mean tighter, more energy-efficient buildings. Step Code requirements are specified in ACH50.
NLA (Normalized Leakage Area)
Another measure of building airtightness expressed as the equivalent leakage area per square meter of building envelope. Some testing protocols use NLA instead of ACH50.
Why Conversions Are Needed
Comparing products from different countries
Understanding building code requirements
Working with contractors who use different systems
Verifying Step Code compliance calculations
Reviewing energy assessment reports
Need More Than Unit Conversions?
Understanding the numbers is just the first step. Professional energy assessments and compliance support help you achieve actual results.
Deep Energy Retrofits
If you’re a homeowner researching energy improvements, our comprehensive evaluations identify exactly where your home is losing energy and how much you can save. We provide detailed reports with prioritized recommendations, cost estimates, and ROI calculations to help you make informed decisions about improving your home’s comfort and efficiency.
Step Code Compliance
If you’re a builder working on permit documentation, our complete Step Code compliance services ensure first-time approval. We handle energy modeling, CSA F280 calculations, municipality-specific formatting, and blower door testing so your projects stay on schedule without compliance delays.
Get Expert Support
Ready to move beyond calculations to actual improvements? Contact us to discuss your specific needs whether you’re planning a home renovation or managing a building project.
