Heat Loss Calculator

This template is a simple heat loss calculator built in Quadratic to help you quickly estimate heat loss by component (walls, windows, roof, ventilation) and approximate monthly heating energy. It’s ideal for anyone exploring how to calculate heat loss without building a model from scratch. You’ll get a clear summary table, a visual chart, and a monthly energy estimate to support fast decision-making.

Key benefits:

Fast, structured heat loss calculation with ready-to-edit inputs
Visual insights to compare components at a glance
Works for single homes or multi-unit buildings
Easy to duplicate for what‑if scenarios

How users interact

1. Enter assumptions in the Parameters panel:

Building size: floors, apartments per floor, average apartment area, ceiling height
Envelope: wall/roof R-values (or U-values), window area and U-value, perimeter exposure
Operation: indoor–outdoor ΔT, air changes per hour (ACH), heating hours/day, days/month

2. Review results:

HeatLossSummary shows heat loss by category and totals in watts (W), including per-apartment and building‑wide figures.
MonthlyEnergy estimates kWh per apartment and total monthly kWh.
A chart highlights where losses are concentrated.

3. Iterate and compare:

Adjust inputs to see how upgrades influence results (e.g., better windows or insulation, lower ACH).
Duplicate the sheet to keep scenarios side by side.
Export tables to CSV or share the file with collaborators.

Tips and best practices:

Keep units consistent (e.g., R vs U; U = 1/R).
Use realistic ΔT values for your climate and season.
Treat outputs as screening‑level heat loss calculations—not a substitute for detailed engineering or Manual J.
For multi-family, verify perimeter/exposure assumptions per unit layout.

Who it’s for

Homeowners and property managers using a house heat loss calculator to estimate savings from upgrades.
Energy auditors and HVAC pros needing a simple home heat loss calculator for early scoping.
Educators and students learning the basics of calculating heat loss.
Builders, designers, and analysts comparing envelope options across designs.

Real-life use cases:

Compare window replacement vs. added attic insulation.
See the impact of reducing ACH with air sealing.
Estimate monthly heating energy for a small apartment building.

Use this template for heat loss calculation, learn how to calculate heat loss step by step, and run quick calculations directly in a spreadsheet-style workspace. It serves as a practical and approachable process for early estimates.