Cooling & Heating Load
Calculation Service
Send us your drawings. We return a complete, ASHRAE or CIBSE-compliant load analysis — room-by-room, with equipment sizing guidance — within 3–5 working days.
HVAC Load Calculation from Drawings — Online, Worldwide
Accurate cooling and heating load calculations are the foundation of every well-engineered HVAC system. Undersized equipment causes occupant discomfort; oversized equipment wastes capital, consumes excess energy, and short-cycles. Green Power Corporation has been performing building load analyses for 30+ years — from single offices to international airports.
Our remote HVAC load calculation service lets engineering firms, contractors, and building owners worldwide access that expertise without travel or retainer. Submit your drawings by email, and we return a stamped-quality calculation report — ready to submit to your authority or use for equipment procurement.
Why Accurate Load Calculations Matter
- Right-sized equipment means lower capital cost and better energy efficiency
- Lenders and authorities often require a formal load calculation report
- LEED, Estidama, and GRIHA rating schemes require verified load data
- Equipment warranties can depend on correct sizing documentation
- Prevents costly on-site corrections during commissioning
Deliverables Included in Every Report
Room-by-Room Cooling Load
Sensible and latent cooling load for every zone, broken down by wall, roof, glass, solar, occupants, lighting, equipment, and infiltration.
Building Total Cooling Load
Summarised cooling tonnage and kW at peak design conditions, with diversity factors applied where appropriate.
Heating Load Analysis
Steady-state winter heating load per zone and building total, for boiler or heat pump sizing.
Equipment Sizing Guidance
Recommended chiller or DX unit capacity, AHU airflow, FCU tonnage per zone — ready for procurement or tendering.
Ventilation Load
Outdoor air sensible and latent loads per ASHRAE 62.1 or project specification, included in totals.
PDF Report + Excel Summary
Professionally formatted PDF calculation report plus an editable Excel summary of all zone and building totals.
Inputs Required
To start a heat load calculation from drawings, we typically need the following. Don't worry if some information is missing — we'll tell you what's essential and what can be estimated.
- Architectural floor plans (PDF, DWG, or Revit — any format)
- Building location / city (for design-day climate data)
- Occupancy schedule and number of people per zone
- Lighting load (W/m² or fixture schedule)
- Equipment and appliance loads per zone
- Wall, roof, and glazing construction details (or we use ASHRAE defaults)
- Ventilation requirements (ASHRAE 62.1, local code, or specify L/s per person)
- Any special requirements (cleanroom, server room, kitchen, etc.)
Delivery Schedule
| Project Size | Standard | Express |
|---|---|---|
| Single zone / small office | 1–2 days | Same day |
| Multi-zone / floor (up to 20 zones) | 3–4 days | 1–2 days |
| Full building (20–60 zones) | 5–7 days | 2–3 days |
| Large complex / hospital / airport | 10–14 days | By agreement |
Express service available at a surcharge. All timelines start from receipt of complete inputs.
30 Years of Real Projects Behind Every Calculation
Any engineer can run a spreadsheet. What sets Green Power Corporation apart is that our engineers have designed, installed, and commissioned the systems we calculate — including the HVAC for Islamabad International Airport, multiple hospital campuses, pharmaceutical manufacturing facilities, and major commercial towers.
When we produce a cooling load calculation from drawings, it's checked against the judgment of engineers who have seen what happens when calculations are wrong in the field. That operational experience is baked into every report we issue.
View Our Project Portfolio →Software We Use
HAP (Hourly Analysis Program) · Hevacomp · Manual ASHRAE calculations with cross-verification · AutoCAD MEP for layout integration
Standards Applied
ASHRAE Handbook of Fundamentals · ASHRAE 62.1 ventilation · CIBSE Guide A & B · Client-specified local codes
Sectors Served
Offices · Healthcare & hospitals · Pharmaceutical & cleanrooms · Hospitality · Retail & F&B · Aviation · Data centres
Want a Quick Estimate First?
Try our free HVAC load calculator — enter your floor area, design temperatures, and space type to get cooling kW, heating kW, tonnage, and a recommended system type in seconds. No drawings needed, no sign-up.
- Cooling & heating loads with breakdown
- Metric and imperial units
- Runs entirely in your browser
For preliminary sizing only. Need a stamped report? Request a quote below.
Request Your Load Calculation Quote
Email us your drawings or fill in the form — we'll respond with a scope and fixed fee within 24 hours.