A Tucson shop fights three heat sources at once: customers opening the door, sun through the storefront glass and a roof that soaks up heat all day. Many shops run on a rooftop package unit, and it should be sized by a proper load calculation. Climate Pros Tucson matches you with a licensed pro for the assessment.

Why is retail harder to cool than an office?

Doors open constantly, which pulls hot air in. Storefront glass lets sun in, especially on west-facing frontage. Lighting and displays add heat of their own. Summer is the stress test: the airport averages about 68 days a year at or above 100F, and the City of Tucson’s summer design temperature is 105F. A unit sized for an average day can fall short on a hot afternoon.

Why do so many shops use rooftop units?

Package units sit on the roof, which saves floor space and keeps noise away from customers. They also put the equipment in the hottest spot on the building, and every service call means roof access. Ask the pro how the unit is accessed and whether a roof hatch or ladder is in place. See split system vs rooftop package unit.

What affects sizing?

A load calculation should account for the space’s size, glass area and orientation, door traffic, lighting, equipment heat and occupancy. Adding a second unit for a front zone can beat one large unit. Ask the pro to show the calculation and explain how it handles the door and glass. Tucson’s energy code is the 2024 IECC with City amendments, climate zone 2B, so ask the pro which code edition applies to your building and whether the City of Tucson or another jurisdiction permits the work. For commercial permits, confirm with the permitting office.

What does the lease decide?

Many retail leases say who owns, repairs and replaces the rooftop unit. Read yours before you call. Ask the landlord who pays for repairs, whether approval is needed to replace equipment and whether a roof contractor must be involved. Also check how roof access works in a shared building.

What can you do cheaply?

  • Keep filters clean
  • Shade or film the storefront glass if the lease allows
  • Check that doors close fully, and look at air curtains for busy entries
  • Set the thermostat on a schedule rather than leaving it on a manual setting
  • Keep the outdoor coil clear of dust and debris

What should the quote cover?

Ask for the load calculation, the equipment model and size, roof work (curb, crane, sealing), electrical changes, controls, maintenance terms and written warranty. Ask for the price in dollars before work starts. Climate Pros Tucson doesn’t set prices. See commercial HVAC for small business, office building HVAC and restaurant HVAC for neighboring cases.

Get the shop assessed

For a shop, start with commercial HVAC. Call (520) 353-2520 and we’ll match you with a licensed local pro. You can also visit the Tucson HVAC hub. Check any contractor’s license at roc.az.gov.