MBE / HUB-Certified Texas MEP
HVAC Tonnage Estimator
Quick rule-of-thumb cooling load for early-phase TX commercial sizing — pick the building type and conditioned area; we return tons of cooling and a recommended RTU range. Use for SD-phase budgeting only; final sizing requires Manual N or block load calc per equipment selection.
Each type has a different sf/ton rule-of-thumb (cooking load, occupancy density, OA requirements).
Conditioned floor area only — exclude unconditioned warehouse, attic, garage.
Climate adjusts the base tonnage — humid = more tons, dry = fewer tons but more reheat consideration.
Estimated cooling load
10.0tons
Basis: Retail at 300 sf/ton standard climate × 3,000 sf = 10.0 tons. Suggested: 2 × 5-ton RTU or 1 × 10-ton split.
300 sf/ton
Industry rule-of-thumb for typical TX commercial. Restaurants drop to 150 sf/ton (cooking load + outdoor air), medical to 250, warehouses up to 500. We refine with Manual N at design phase.
Need this sized properly with Manual N?
Pyra Engineering produces sealed HVAC load calcs and equipment selections for TX commercial. Quote in 1 business day.
Important. This is a rule-of-thumb early-phase estimate only. Final cooling load requires room-by-room Manual N or block-load calculation accounting for envelope, glazing, occupancy, plug load, and outdoor air. Permit submittal requires sealed drawings from a licensed engineer.