Confirm which ventilation standard and edition the adopted mechanical or energy code requires, then trace each system’s outdoor air from the ventilation calculation into the equipment schedule, the duct and diffuser plans, the controls sequence, and the roof plan, and check intake locations against exhaust and other sources. AI can flag conflicts; the mechanical engineer and the code official decide compliance.
What does ASHRAE 62.1 cover?
ASHRAE’s bookstore lists ANSI/ASHRAE Standard 62.1-2025, Ventilation and Acceptable Indoor Air Quality, and describes it as covering mechanical and natural ventilation systems, including requirements for filtration, controls, air cleaning systems, and building operations and maintenance. ASHRAE describes 62.1 and its residential companion as specifying minimum ventilation rates and other measures to minimize adverse health effects for occupants. Standard 62.2-2025 covers dwelling units in residential occupancies whose occupants are nontransient.
The ASHRAE bookstore page lists the 2025 edition, with new provisions for humidity control, demand-controlled ventilation sequences, ventilation emergency controls, and exhaust and separation-distance methods. ASHRAE’s read-only standards page offers free viewing of 62.1-2025 and earlier editions. Both checked October 6, 2026. The mechanical code a jurisdiction adopts has its own ventilation chapter and may reference a specific edition; record which document and edition the project uses.
Mechanical code reviews continue in the IMC guide and the UMC guide, and energy recovery and fan power questions in the ASHRAE 90.1 guide. Health care spaces may follow ASHRAE 170 instead.
Gather the ventilation calculation and the systems it describes
Collect the ventilation calculation or schedule by zone, the air handling unit and dedicated outdoor air unit schedules, the duct and diffuser plans, the roof plan and elevations with intake and exhaust locations, the exhaust fan schedule, the controls sequences and points lists, the filter specifications, and the HVAC specification sections.
Outdoor air values are often stated three times: in the calculation, the unit schedule, and the sequence. Upload all three so they can be compared.
Follow the outdoor air from calculation to space
| Review question | Sources to compare | Decision to record |
|---|---|---|
| Standard and edition | Mechanical notes, calculation cover, specifications | Confirm one ventilation standard and edition across documents. |
| Outdoor air quantities | Ventilation calculation, unit schedules, controls sequence | Match each system’s outdoor air between the calculation, schedule, and sequence. |
| Zones and spaces | Ventilation calculation, floor plans, room names | Find spaces whose use or area changed after the calculation. |
| Intakes and exhaust | Roof plan, elevations, exhaust fan schedule | Check intake locations against exhaust outlets and other sources, with the classification each side uses. |
| Demand control | Controls sequence, sensor locations, schedules | Confirm sensors and sequences named in one document appear in the others. |
| Filtration | Unit schedules, specifications | Reconcile filter ratings between the schedule and specification. |
Dedicated outdoor air units follow the DOAS specifications guide, sequences the HVAC controls guide, and the full review log the mechanical drawing checklist.
Example: intake and exhaust use different separation criteria
Published finding. In Groundbook’s published waterfront hotel review, the roof plan showed a separation between a kitchen exhaust outlet and an outside-air intake based on one exhaust rule, while the intake had a different requirement for the kitchen exhaust classification.
Exhaust and outside-air intake use different separation criteria: the roof plan’s separation follows one exhaust rule, while the intake requirement for the kitchen exhaust classification differs.
The mechanical engineer identifies the actual exhaust classification, checks the intake and discharge rules together, and documents a coordinated layout or a supporting calculation. Rooftop equipment may move.
Review ventilation with Groundbook
Upload the current drawings and specifications to Groundbook, and state the edition, amendments, and review scope in your instructions. Add the ASHRAE 62.1 edition the project uses from a copy you are licensed to use, where the license permits uploading it, along with the adopted mechanical code and amendments. See how Groundbook works with local and licensed codes.
Compare the ventilation calculation with the air handling and outdoor air unit schedules, duct and diffuser plans, controls sequences, roof plan, elevations, exhaust fan schedule, and specifications. Flag outdoor air quantities that differ between sources, spaces changed after the calculation, intakes near exhaust or other sources, and sensors named in only one document. Use the supplied ASHRAE 62.1 edition and the adopted mechanical code and cite both sources.
Groundbook links each potential finding to the sheets and schedules involved.
Document review does not calculate ventilation rates or separation distances and does not replace the mechanical engineer or the code official.