Today's high-performance homes are built tighter, more efficient, and more durable than ever. But many builders are seeing the same issue: homeowners report comfort problems and moisture concerns in homes that pass inspections and meet code requirements.

Tight Homes Change Airflow

Better air sealing, spray foam, and improved construction practices reduce air leakage and make homes more energy efficient. But tighter homes also change how air moves.

When exhaust fans, range hoods, or dryers remove air from a tight home, replacement air has to come from somewhere. If the home does not have a balanced ventilation strategy, outdoor air can be pulled in through unwanted paths such as wall assemblies, attics, crawlspaces, and small gaps in the building envelope.

Many codes now require mechanical ventilation once homes reach certain airtightness levels. When ventilation systems are missing, improperly sized, or unbalanced, the home can struggle to maintain proper pressure and humidity control. The result is often poor comfort, higher humidity, and increased homeowner complaints.

Oversized HVAC Systems Create Moisture Problems

Another common issue is HVAC equipment that is larger than the home actually needs.

When equipment is selected without accurate load calculations, systems may cool the home quickly and shut off before they have enough runtime to remove moisture. The thermostat may show the correct temperature, but the home can still feel uncomfortable.

Proper HVAC sizing using Manual J and Manual S helps ensure equipment runs long enough to control both temperature and moisture. 

Why Runtime Matters

Air conditioning removes both heat and moisture. Moisture removal happens when warm, humid air passes over a cold evaporator coil long enough for water vapor to condense and drain away.

Short cycling prevents that process from working effectively. The system cools the air but does not run long enough to properly dehumidify the home.

Why It Matters

Modern comfort issues are usually system-integration issues rather than individual component failures. Preventing humidity problems requires the envelope, ventilation system, and HVAC equipment to work together from the start.

ARCXIS helps builders identify and correct these issues early through integrated HVAC design, energy modeling, ventilation strategy review, field verification, airflow testing, HVAC commissioning, and forensic warranty support, all of which guide evidence-based decision-making and complaint resolution. Contact your local team at: https://arcxis.com/markets