Size Your HVAC System with
Real Physics, Not Rules of Thumb
Enter your building details to get an instant system recommendation and load estimation across central heating, heat pumps, and split systems. When you’re ready, apply for a full detailed engineering project.
Instant HVAC Recommendation
Enter your building's basic parameters. We'll calculate the thermal load and suggest the most efficient system topology for your specific climate and scale.
Curious what the recommended system costs?
The suggestion above points you to a system type and capacity. Our Energy Prices page tracks indicative average market prices for heat pumps, boilers and pumps by brand, useful for early budgeting, ahead of a detailed calculation and quote.
From floor plans to precise climate control
We use AI to accelerate data processing and load modeling, then our engineers review and verify every step before it reaches your inbox.
Data intake & weather
We analyze your architectural plans, orientation, and local TMY weather files to understand the exact thermal behavior of your building.
Room-by-room load calc
Using ASHRAE, EN 12831, or Manual J standards, we calculate the exact heating and cooling load for every single zone.
System selection & sizing
We select the optimal topology (Heat Pump, VRF, Chiller) and size the equipment perfectly to prevent short-cycling and energy waste. AI helps us compare dozens of configurations fast; a licensed engineer verifies and finalizes the selection.
Distribution design
We design the ductwork, piping, and terminal units (fan coils, radiators) ensuring optimal airflow, pressure drop, and acoustic comfort.
Documentation & BOM
You receive detailed schematics, a Bill of Materials with exact specifications, and clear installation guides for your contractor. Every report is AI-drafted and engineer-reviewed before it reaches you.
What lands in your inbox
Every calculation package is produced with AI assistance and personally reviewed by our engineering team before delivery.
Thermal load report
Room-by-room heating and cooling loads calculated to ASHRAE, Manual J, or EN 12831 standards.
Equipment schedule
Exact capacities, airflow rates, and a Bill of Materials ready for procurement, with the brand choice left to you.
Distribution schematics
Ductwork layouts, piping diagrams, and pressure drop calculations for perfect airflow balance.
Control & wiring
Thermostat placement, control logic sequences, and wiring diagrams for the automation integrator.
Acoustic & airflow
Noise criteria (NC) checks, CFM/L/s airflow balancing, and diffuser selection for silent comfort.
Install & commissioning
A step-by-step manual for your contractor, including testing protocols and final balancing guides.
The office that froze and overheated
A 400m² commercial space suffering from a legacy oversized boiler and an undersized, short-cycling AC system. We recalculated the zone loads and engineered a variable refrigerant flow (VRF) solution.
- Baseline: 185 kWh/m²/yr energy use, constant tenant comfort complaints.
- The Fix: Right-sized VRF system with dedicated zone controls and heat recovery.
- Result: 38% drop in energy bills, zero thermal complaints, and a 12-year projected ROI.
Request a Detailed Project
Ready when you are
Tell us about your building. We'll reply with a tailored scope, timeline, and a fixed quote for your detailed HVAC calculation.
Common questions
Why do I need a professional calculation? Can't my installer just size it?
Installers often use "rules of thumb" (like 1 ton of cooling per 600 sq ft), which frequently leads to oversized or undersized equipment. An oversized system will short-cycle, causing humidity issues, temperature swings, and premature failure. Our calculations (Manual J / ASHRAE) guarantee the exact capacity your building's physics demand.
What engineering standards do you use?
We strictly follow internationally recognized standards. For residential, we use ACCA Manual J (load), Manual D (ducts), and Manual S (equipment selection). For commercial or European projects, we use ASHRAE fundamentals or EN 12831. This ensures your design is compliant, efficient, and defensible.
Do you sell the HVAC equipment?
No. We do not sell hardware, and we do not take commissions from manufacturers. Our advice is based on your project needs, not sponsorships, and you always choose the brand or device model. We provide a detailed Bill of Materials (BOM) with exact specifications. This allows you to get competitive bids from any local supplier or installer without being locked into a specific brand.
Can you design a system for an existing home (retrofit)?
Absolutely. For existing homes where adding ductwork is impossible or too expensive, we specialize in designing high-efficiency ductless solutions (like multi-split or VRF systems). We calculate the exact placement of indoor heads to ensure perfect airflow and aesthetic integration.
How long does a detailed HVAC calculation take?
A standard residential calculation and design package typically takes 5 to 10 working days from the moment we receive complete architectural plans and window schedules. Larger commercial projects or complex retrofits are scoped individually based on the building's footprint.
Is AI used in your HVAC calculations?
Yes. We use AI tools to speed up data processing and initial load modeling, but every calculation is reviewed and signed off by a qualified engineer before it's delivered. AI handles the heavy lifting; a human is always responsible for the final numbers.
Designed by engineers, built by trusted pros
Our network connects people who plan energy projects with vetted local installers and technicians.
Need an HVAC installer?
Have your load calculation or a heating and cooling plan ready? Tell us where you are and we connect you with vetted local HVAC and heat pump installers.
HVAC contractor or heat pump installer?
Join our partner network to get listed in our directory and receive project enquiries from people planning heating and cooling work.