How Should HVAC Be Engineered for a Veterinary Clinic Building?

I divide the clinic into at least three air systems: public and exam areas on comfort HVAC with premium filtration, clinical areas (treatment, surgery, dental, lab) on higher-ventilation systems with tight environmental control, and animal housing (kennels, runs, isolation) on dedicated exhaust-heavy ventilation. Lobby and offices can share the public system. The kennel system never shares return air with the rest of the building. This zoning is the foundation — it lets exam rooms stay quiet and comfortable while kennels get the aggressive ventilation they need, and it makes energy code compliance manageable because each system's recovery and controls match its actual load.

Air should always move from clean to less-clean spaces. I design exam rooms neutral or slightly positive to corridors, corridors neutral to kennel entries, and kennels negative to everything around them. Isolation wards sit the most negative of all. Supply and exhaust placement within each room matters too — in kennels I push supply air across the runs so it sweeps toward the exhaust grilles, carrying dander and odor out instead of letting it settle. Doors get proper undercuts or transfer grilles sized for the pressure design, because a pressure scheme that depends on leaky doors is not a scheme at all.

This is the checklist I run before a clinic HVAC design is finished. Every item protects either animal health, staff health, or the client's first impression. • Separate zones for exam comfort, clinical areas, and kennel exhaust with no shared return air between them • Pressure cascade: exam rooms neutral to positive, kennels negative, isolation most negative • Filtration sized for dander and hair with low face velocity and genuinely accessible filter banks • Dedicated kennel exhaust with energy recovery where the climate and code make it pay • Humidity control in kennels to handle washdown moisture and keep the space healthy