Home Health Inspections LLC

📞 Service Area Statement:

We proudly serve clients throughout Skagit, Snohomish, Whatcom, Island, and San Juan Counties — and will travel anywhere within Washington State as needed.

*Additional travel fees may apply for inspections outside our primary service region.

Carbon Dioxide

Carbon Dioxide in the Home – A Homeowner’s Guide to Understanding and Managing CO₂

What is Carbon Dioxide?

Carbon dioxide (CO₂) is a naturally occurring gas that is part of the air we breathe. It’s colorless, odorless, and a normal byproduct of breathing, combustion, and many household activities.

  • Outdoors, CO₂ levels are usually harmless and easily dispersed.
  • Indoors, however, CO₂ can build up — especially in tightly sealed homes — and contribute to poor air quality.
  • While CO₂ itself is not toxic in small amounts, elevated levels can make indoor spaces feel stuffy, uncomfortable, and unhealthy.

Where Does Carbon Dioxide Come From in the Home?

Carbon dioxide is produced by everyday activities and appliances. Common sources include:

  • People and pets: every breath releases CO₂. Crowded rooms can quickly lead to high levels.
  • Combustion appliances: gas stoves, fireplaces, furnaces, and water heaters.
  • Poor ventilation: tightly sealed windows and doors trap CO₂ indoors instead of letting it escape.
  • Vehicles: attached garages can sometimes allow CO₂ buildup if cars are left running.

Homes that are newer and energy efficient often have higher indoor CO₂ levels because they’re designed to keep outside air out — which also means less fresh air circulation.

Why is Carbon Dioxide a Concern?

While CO₂ isn’t considered poisonous like carbon monoxide, high concentrations indoors can cause health and comfort problems.

  • Short-term effects: headaches, fatigue, drowsiness, difficulty concentrating, and a feeling of “stale air.”
  • Long-term effects: prolonged exposure to high levels may worsen sleep quality, increase stress on the respiratory system, and reduce overall well-being.
  • Indirect health impact: high CO₂ is often a sign of poor ventilation, which can also allow other indoor pollutants (like VOCs, formaldehyde, and moisture) to build up.

Children, the elderly, and those with respiratory conditions may be more sensitive to elevated CO₂ levels.

Why Should Homeowners Care About CO₂?

Carbon dioxide is a good indicator of indoor air quality.

  • If CO₂ levels are high, it usually means that other pollutants are also accumulating indoors.
  • In homes, schools, and offices, high CO₂ has been linked to lower productivity, poor sleep, and increased illness.
  • Reducing indoor CO₂ isn’t just about comfort — it’s about ensuring your family has a healthy breathing environment.

What if CO₂ Levels are High in My Home?

If your home has elevated CO₂, the solution almost always involves improving airflow and ventilation. Steps may include:

  • Increase ventilation: open windows, run exhaust fans, or use whole-home ventilation systems.
  • Upgrade HVAC systems: ensure your heating and cooling systems are moving enough fresh air throughout the home.
  • Add plants: while not a complete solution, indoor plants can help absorb some CO₂ and improve perceived air quality.
  • Limit indoor combustion: avoid idling cars in attached garages and ensure stoves and fireplaces are properly vented.

Tips for Keeping CO₂ Levels Low

  • Open windows and doors when weather permits to bring in fresh air.
  • Use energy-recovery ventilators (ERVs) or heat-recovery ventilators (HRVs) in airtight homes.
  • Run bathroom and kitchen exhaust fans to vent air outside.
  • Maintain HVAC filters and ductwork to ensure good airflow.
  • Be mindful of time spent in crowded, poorly ventilated rooms — especially bedrooms and offices.

The Bottom Line

Carbon dioxide is a normal part of the air we breathe, but too much of it indoors is a sign of poor ventilation and can affect both comfort and health.

  • High CO₂ levels = poor indoor air quality.
  • Improving ventilation is the key to reducing buildup.
  • Healthier air means better sleep, focus, and overall well-being.

A Home Health Inspection that checks for CO₂ levels and overall indoor air quality can help you identify ventilation issues and create a fresher, safer home environment.