Need to size the air conditioning for a workshop? Workshops and light-industrial spaces gain heat from machinery, tools, and large doors, giving a cooling factor near 25 BTU/sq ft. Keeping a workshop cool improves both worker comfort and the accuracy of temperature-sensitive work. The calculator below is pre-set to a workshop at 500 sq ft — a workshop that size typically needs about a 1.5 Ton AC (15,125 BTU/hr, 4.4 kW) in a moderate climate. Enter your own area for an instant answer.
Unique HVAC Demands for a Workshop
When calculating the AC tonnage for a Workshop, standard residential square-footage rules of thumb will lead to disastrously incorrect sizing. This is because a Workshop introduces highly specific internal heat loads, specifically: heat-generating machinery, dust collection systems, and open bay doors.
A workshop’s AC must combat not just the ambient heat, but the radiant heat from tools and motors. Dust-proof evaporator coils and high-MERV filtration are absolutely critical to prevent the system from clogging. Use the calculator below to factor in these unique commercial variables and get an accurate estimate of the required cooling capacity.
🧊 Find the Right AC Size for Your Room — in Tons & BTU
Convert room size (sq ft or m²) to the exact AC tonnage you need — 0.5, 1, 1.5, 2 Ton and up. ACCA Manual-J inspired, in tons, BTU/hr and kW, for the US, UK, Europe, India, UAE, Saudi Arabia & Australia.
🌍 Prefer metric? Switch units here
🏠1. Space Type
📐2. Floor Area & Ceiling
Range: 50 – 10,000 sq ft
Range: 7 – 20 ft
Range: 0 – 50 people
🌍3. Country / Climate
The base factor assumes a 30 °C / 86 °F design day. Change the chip above to match your region.
🧱4. Insulation
☀️5. Sun Exposure
🪟6. Windows / Glazing
➕Advanced loads (kitchen, appliances, exhaust) — optional
Wattage × 3.4 = BTU/hr. e.g. 500 W ≈ 1,700 BTU/hr
For office IT, gym gear, lab equipment
Workshop AC Size by Floor Area
Typical AC tonnage for a workshop with an 8-foot ceiling and average conditions. Heavy equipment, high occupancy, or a hot climate will push these up — adjust those in the calculator:
| Workshop Size | Recommended AC | Approx. BTU/hr |
|---|---|---|
| 300 sq ft | 1 Ton | 9,075 BTU/hr |
| 500 sq ft | 1.5 Ton | 15,125 BTU/hr |
| 800 sq ft | 2.5 Ton | 24,200 BTU/hr |
| 1,200 sq ft | 4 Ton | 36,300 BTU/hr |
| 2,000 sq ft | 5 Ton | 60,500 BTU/hr |
Sizing AC for a Workshop — What to Consider
Add machine and equipment heat with the equipment field, and account for large roller-doors that let heat in. Spot-cooling the work areas is often more efficient than trying to cool an entire high-bay workshop to a uniform temperature. The calculator applies the workshop heat-gain factor automatically; use the advanced fields (occupants, equipment, appliances, ventilation) to match your exact space, and remember an oversized unit short-cycles and dehumidifies poorly — right-sizing gives better comfort and lower running cost.
Frequently Asked Questions
What size AC do I need for a workshop? A 500 sq ft workshop typically needs about a 1.5 Ton AC (15,125 BTU/hr) in a moderate climate; scale up or down with your floor area per the chart above.
What size AC for a workshop? Around 25 BTU/sq ft plus machinery heat. Large open workshops are often spot-cooled at the work areas rather than cooled uniformly throughout.
How many BTU per square foot for a workshop? Roughly 25 BTU/sq ft as a starting factor, before adjusting for climate, ceiling height, occupancy, and equipment heat.
Background reading: how the refrigeration cycle works.
Estimates vary by contractor. Compare free quotes from licensed local pros before you commit. Request a quote →
High-efficiency systems may qualify for utility rebates and federal or state incentives. Find current programs at ENERGY STAR & DSIRE.
Figures are reviewed by the Refcon HVAC engineering team using U.S. DOE, ENERGY STAR & ACCA Manual J data. Estimates only — confirm with a licensed pro.