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Updated: Dec 27, 2025
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Tracking Infiltration Front Depth Using Time-lapse Multi-offset Gathers Collected with Array Antenna Ground Penetrating Radar
Published on: May 1, 2018
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Estimating real-time infiltration for use in residential ventilation control.
Lisa C Ng1, Stephen Zimmerman1, Jeremy Good2
1National Institute of Standards and Technology.
Summary
Real-time ventilation control can save energy by adjusting mechanical ventilation based on actual infiltration rates. This strategy offers energy savings without compromising occupant exposure compared to constant ventilation rates.
Area of Science:
- Building Science
- Indoor Air Quality
- Energy Efficiency
Background:
- Current ventilation standards (e.g., ASHRAE Standard 62.2) use fixed infiltration credits.
- Infiltration rates fluctuate with weather and system operation, leading to potential inefficiencies.
- Real-time knowledge of infiltration could optimize mechanical ventilation.
Purpose of the Study:
- To evaluate a real-time ventilation control strategy.
- To compare energy use and occupant exposure with a constant ventilation rate.
- To assess the feasibility of adjusting mechanical ventilation based on measured infiltration.
Main Methods:
- Utilized CONTAM models of two NIST test houses, verified with measurements.
- Simulated hourly infiltration rates in three distinct cities.
- Developed a theoretical controller to adjust mechanical ventilation based on real-time infiltration data.
Main Results:
- The real-time control strategy demonstrated annual average energy savings of $66 USD.
- No increase in annual occupant exposure was observed compared to constant ventilation.
- Simulations were conducted across two houses and three cities.
Conclusions:
- Real-time ventilation control is a viable strategy for reducing energy consumption.
- The proposed method optimizes mechanical ventilation without negatively impacting indoor air quality.
- Further discussion on the advantages and limitations of this approach is warranted.
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