HeatHome Designer — Residential Heat-Pump Load & Zoning Tool

Screen residential heat-pump loads by room with editable presets, climate, envelope, capacity and zoning inputs plus thermal views and exports.

What this tool does

HeatHome Designer is a browser-based preliminary residential heating and cooling load calculator. It models a home’s geometry, envelope, climate, room sizes, windows and occupants, then estimates room-level and building-level loads for heat-pump capacity and zoning exploration.

When to use this tool

Use HeatHome Designer when you need an early room-by-room heat-pump load, capacity or zoning comparison before selecting equipment or requesting a professional HVAC design.

Who this is for

• HVAC designers and energy analysts preparing early residential system studies
• Homeowners, builders and facility teams comparing envelope and equipment scenarios before professional design
• Students and educators learning how room geometry, U-values, air changes, design temperatures and equipment performance affect loads

How to use this tool

1. Choose a house preset such as a bungalow, two-storey home or townhouse, then apply it to create editable rooms.
2. Set building width, depth, storeys, ceiling height, envelope standard or custom U-values, and air changes.
3. Choose a climate preset or enter winter and summer design temperatures, indoor setpoints and heating/cooling conditions.
4. Enter the heat-pump system type, rated heating and cooling capacity, cold-weather retention, COP values and sizing margin.
5. Select rooms to edit their name, floor, room type, dimensions, window area and occupants. Add or remove rooms as needed.
6. Run Calculate, then review the 3D thermal house, floor plan, load breakdown, capacity/balance-point view, room details, suggested zoning and report.
7. Save the project locally, open a JSON project, export JSON or room-load CSV, capture a PNG thermal view, or print the report.

Inputs

Inputs include house preset, building dimensions, storeys, ceiling height, envelope U-values, air changes, climate and design temperatures, indoor heating/cooling setpoints, heat-pump system type, rated capacity, cold-weather retention, COP values, sizing margin, room type, room dimensions, floor, window area and occupants.

Outputs

Outputs include estimated heating and cooling loads, design capacity, auxiliary heat, balance point, floor area, room-level heat intensity, envelope load breakdown, suggested zoning, estimated COP and annual energy indicators, plus 3D thermal, floor-plan, load, capacity and printable report views.

Example use cases

• Compare a legacy, standard and high-performance envelope for the same house preset.
• Test whether a preliminary heat-pump capacity covers a home’s winter design load or leaves an auxiliary-heat gap.
• Explore room-level loads and preliminary zoning for ducted, multi-zone or floor-based system concepts.

Limitations and responsible use

This is a preliminary screening and education tool, not a Manual J, CSA, code-compliance, permit or equipment-selection substitute. Results depend on simplified entered assumptions and do not replace verified construction details, orientation and shading analysis, ventilation and infiltration design, duct or hydronic distribution design, manufacturer performance tables, electrical checks, comfort review or professional commissioning.

Heat-pump capacity, COP and balance-point results are screening estimates. Confirm cold-weather performance, defrost behavior, minimum modulation, auxiliary heat, airflow, refrigerant or hydronic requirements, local climate data and applicable regulations with a qualified HVAC professional.

Projects are saved in the browser and can be exported as JSON for portability. Browser storage may be cleared, so export a project file when a durable copy is needed.

Frequently asked questions