Introducing The Spring Street Passive House: A Healthy Home Project By Kristof & Diane Irwin

For two decades, our work at Positive Energy has been driven by a single, powerful question: why aren’t buildings created to better support the people inside them? We’ve dedicated our careers to answering that question, moving from hands-on custom home building to the forefront of building science and MEP engineering. Now, we’re bringing that journey full circle by taking on our most personal project yet: our own family home, the Spring Street Passive House.

Architectural Design, Building Enclosure, Building Science, Dehumidification, Electrification, Embodied Carbon, Environmental Design, Filtration, Healthy Home, Heat Pumps, High Performance Homes, HVAC, Indoor Air Quality, Mechanical Design, Natural Building Material, Passive House, Phius, Plumbing, Solar, Ventilation, WildfirePositive EnergyJuly 3, 2025Spring Street Passive House, Resilient Design, Human-Centered Design, Columbia River Gorge, Positive Energy, MEP Engineering, Building Science, Diane Irwin, Kristof Irwin, Blue Heron Builders, Diagnostic Performance Testing, Forensic Building Science, Human and Planetary Thriving, The Building Science Podcast, Passive House Standard, Passivhaus, Fabric-First Approach, Phius Standard, Phius CORE, Phius ZERO, Thermal Control, Continuous Insulation, Thermal Bridge Elimination, Air Control, Airtight Construction, Blower Door Test, Balanced Ventilation, Heat Recovery Ventilator (HRV), Energy Recovery Ventilator (ERV), Radiation Control, High-Performance Windows, Triple-Glazed Windows, Optimized Solar Gain, Shading, WUFI Passive Software, Moisture Control, Occupant Health, Building Durability, Extreme Winds, Temperature Extremes, Wildfire, Air Quality, Geological Conditions, Soil Conditions, Foam-Free Enclosure, Embodied Carbon, All-Electric Design, Radiant Heating, Radiant Cooling, Air-to-Water Heat Pumps, Net-Zero Energy Building, Rooftop Solar Array, Thermal Comfort, Indoor Air Quality, MERV Filters, Acoustic Comfort, Psychological Security, Environmental Pollutants, Sustainable Housing, Building Decarbonization.

The Electrification of Domestic Hot Water: Heat Pump Water Heater Adoption in U.S. Residential Construction

The residential construction market in the United States is undergoing a fundamental transformation, driven by the dual imperatives of grid modernization and enhanced indoor air quality. Central to this shift is the increasing adoption of Heat Pump Water Heaters (HPWHs). These highly efficient, all-electric systems represent a critical technology for decarbonizing buildings and fostering a more resilient energy infrastructure. While current national adoption rates remain modest, market dynamics indicate a significant acceleration, propelled by robust governmental policies, escalating consumer interest in new construction, and continuous technological advancements.

Plumbing, Electrification, Heat PumpsPositive EnergyMay 22, 2025Heat Pump Water Heaters (HPWHs), U.S. Residential Construction Market, Grid Modernization, Indoor Air Quality, Decarbonization, Energy Infrastructure, Governmental Policies, Consumer Interest, Technological Advancements, Heat Transfer, Energy Savings, Combustion Byproducts, Installation Complexities, Upfront Costs, Emergency Replacements, Incentives, Workforce Development, Consumer Education, All-Electric Homes, Clean Energy Transition, Building Emissions, Heat Decarbonization, Electric Grid Transformation, Distributed Energy Resources (DERs), State-Level Policy Goals, Energy Ecosystem, Societal Shift, Architects' Role, Thermal Energy, Electric Resistance Water Heaters, Energy Bill Savings, Market Dynamics, Growth Trajectory, Market Size (USD), Compound Annual Growth Rate (CAGR), Global Market, HPWH Sales, National Adoption Rate, Consumer Preference, New Construction Integration, North America, Eco-Conscious States, Market Nuance, Housing Stock Retrofits, Manufacturers (Rheem, A. O. Smith, Bradford White, Vaughn, Nyle Systems), Sales Targets, Policy Changes, DOE Efficiency Standards, Inflation Reduction Act (IRA), Tax Credits, Rebates, Energy Savings Standards, Carbon Dioxide Emissions Reduction, Appliance Standards Program, Home Electrification and Appliance Rebate Program, ENERGY STAR Certification, Low-to-Moderate Income (LMI) Households, State and Local Programs, Utility Rebates, Time-of-Use Pricing, Economic Stimulus, Supply Chain, Job Creation, Energy Equity, Market Transformation Strategy, Grid Resilience, Public Health, Flexible Loads, Thermal Storage, Electricity Consumption Timing, Peak Electricity Demand, Grid-Interactive HPWHs, Infrastructure Investment, Grid Reliability, National Energy Security, Sustainability Goals, Demand Management Programs, Load Shifting, Renewable Energy Integration, Grid Stability, Grid Efficiency, Grid-Interactive Efficient Buildings (GEBs), Transactive Energy, Load Swings, Economic Benefits, Future-Proof Energy Infrastructure, On-Site Combustion Elimination, Toxic Combustion Exhaust Gases, Pollutants, Fire/Explosion Risk, Fossil Fuel-Burning Appliances, Carbon Monoxide (CO), Nitrogen Dioxide (NO2), Particulate Matter (PM, PM2.5), Sulfur Dioxide (SO2), Hydrocarbons (Benzene), Aldehydes, Vented Combustion Devices, Unvented Combustion Devices, Source Control, Ventilation, Indoor Air Quality Concerns, Health Benefits, Vulnerable Populations, Environmental Advantages, Reduced Carbon Footprint, Greenhouse Gas Emissions, Technology Maturation, Reliability, Sound Reduction, Installer-Friendly Features, High Upfront/Installation Costs, Retail Prices, Contractor Installations, Skilled Labor Shortage, HVAC/Plumbing Trades, COVID-19 Impact, Installer Training, Project Completion Times, Improper Installations, Workforce Gap, Post-Installation Startup Process, Diagnostic Run Times, Electric Element Behavior, Consumer Awareness, Long-Term Cost Savings, Installer/Consumer Bias, 120V Plug-In Models, Retrofit-Ready Solutions, Holistic Building Design, MEP Engineers, Building Science Consultants, Point-of-Sale Rebates, Direct-to-Contractor Incentives, Tax Credits/Rebates Communication, Licensing Pathways

The Damp Deception: How a Well-Intentioned Code Change is Fostering Mold in New Homes

The promise of a new home often includes visions of a healthier, more energy-efficient living space. However, a subtle yet significant regulatory shift in U.S. building codes, particularly affecting hot-humid climate zones, may be inadvertently undermining this very promise. Before 2021, residential ventilation requirements were often loosely enforced; homes were typically required to have a ventilator, but the actual volume of air exchanged was not mandated to be measured. This frequently led to systems being ineffectively installed or even "sabotaged" by HVAC contractors, rendering them inoperable or improperly configured from the outset. Consequently, many homes, even in that period, did not achieve consistent fresh air exchange. Compounding this, most residential HVAC systems lacked any form of supplemental or dedicated dehumidification, a feature that building science experts have increasingly recognized as crucial, especially for high-performance homes in moisture-laden environments.

What Have We Learned About Air Conditioning & The Coronavirus

In an effort to broadly provide resources to our clientele and audience, we’ve written articles on the topics of health precautions for construction job sites and designing for healthy environments while reducing pathogen spread. We’ve released podcast episodes on the impact of ventilation and filtration on virus transmission. But now it’s time to talk about a serious elephant in the room as it pertains to coronavirus spread - air conditioning.

Indoor Air Quality, HVAC, COVID, Healthy Home, Filtration, VentilationPositive EnergyAugust 31, 2020SARS-CoV-2, COVID-19, Air Conditioning, Indoor Air Quality, Ventilation, Filtration, Masks, Humidity, Aerosols

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