HVAC Checklist for New Construction: What Every Builder Needs to Know

New builds move fast. HVAC problems don’t show up until the end—when fixes cost the most.

This checklist helps builders avoid change orders, comfort complaints, and “why is this room always hot?” calls.

Phase 1: Planning (before framing is locked)

Goal: Make the HVAC plan match the floor plan—before it’s expensive to change.

• Confirm equipment type (furnace/AC, heat pump, hybrid) based on budget + climate

• Run a heat loss / heat gain calculation (don’t guess)

• Plan the mechanical room: service clearance, filter access, drainage, power

• Map supply + return locations per room (avoid dead zones)

• Decide if you need zoning (2-story homes often do)

• Choose ventilation plan (bath fans and/or HRV/ERV)

• Lock outdoor unit location: airflow clearance, noise, snow/drainage, line-set path

Phase 2: Rough-in (framing stage)

Goal: Install ductwork and pathways right the first time.

• Duct runs planned for short + straight routes where possible

• Returns are sized and placed to prevent pressure issues (doors slamming, whistling)

• No crushed flex duct; bends kept smooth

• Proper pathways for:

  • refrigerant lines (if AC/heat pump)

  • condensate drain

  • exhaust/intake (if required)

  • thermostat and control wiring

• Confirm insulation/air sealing plan so HVAC isn’t fighting a leaky house

Phase 3: Equipment selection (not one-size-fits-all)

Goal: The system fits the home—not the other way around.

• Equipment sized to the calculation, not square footage rules

• Prioritize:

  • variable-speed blower (comfort + quieter)

  • smart thermostat compatibility

  • proper filtration options (especially for families with allergies)

• Confirm warranty requirements (some depend on installer + setup)

Phase 4: Installation (make-or-break moment)

Goal: Great gear can still perform badly if installed poorly.

• Installed by qualified HVAC pros

• Duct connections sealed properly (leaks waste airflow)

• Refrigerant lines installed correctly (if applicable)

• Condensate drain tested

• Controls/thermostat installed in a sensible location (not near drafts/sun)

Phase 5: Quality checks + commissioning (don’t skip this)

Goal: Prove it works before handoff.

• System startup checks completed

• Air balancing performed (so each room gets the right airflow)

• Temperature split and airflow verified

• Ventilation tested (bath fans/HRV/ERV)

• Final walkthrough: filter access, shutoffs, thermostat basics, maintenance schedule

Builder handoff checklist (what to give the owner)

• System specs + manuals

• Warranty info + installer contact

• Filter size + replacement schedule

• Thermostat quick-start

• Recommended seasonal maintenance

Want your new build HVAC done right the first time?

If you’re building a new home or managing a new construction project, we can help you plan, rough-in, install, and commission the HVAC system so it performs on day one—without last-minute surprises.

FAQs

What’s the #1 HVAC mistake in new construction?
Skipping proper sizing and planning. Guessing leads to comfort problems and callbacks.

When should HVAC planning happen in a new build?
Before framing is locked—so supply/return locations and duct routes fit the layout.

Do new builds need ventilation like an HRV/ERV?
Many tighter homes do. It helps manage fresh air and humidity. Your HVAC pro can confirm what fits your build.

Is zoning worth it for a two-story home?
Often, yes—especially if rooms heat/cool unevenly.

What is commissioning and why does it matter?
It’s the final testing and setup to prove the system runs correctly (airflow, controls, safety checks).

How do I reduce HVAC change orders during construction?
Lock equipment type, duct paths, outdoor unit placement, and control wiring early—then verify at rough-in.