Posts tagged net-zero energy buildings

The Theresa Passive House: A Blueprint for High-Performance Design in Hot-Humid Climates

The Theresa Passive House, nestled in Austin's historic Clarksville neighborhood, stands as a remarkable example of how architectural preservation can harmoniously merge with modern sustainable design. This 2100 square foot residence, completed in 2020, is not merely a renovation and addition to a 1914 Craftsman bungalow; it is a meticulously engineered dwelling that embodies rigorous targets in energy efficiency, indoor air quality (IAQ), thermal comfort, embodied carbon, and responsible materials sourcing.[1] These ambitious goals were established by the Passive House Institute U.S. (Phius), a leading authority in high-performance building standards.

Architectural Design, Building Enclosure, Building Science, Code, Dehumidification, Electrification, Environmental Design, Filtration, Healthy Home, Heat Pumps, High Performance Homes, HVAC, Indoor Air Quality, Mechanical Design, Passive House, Phius, Solar, VentilationPositive EnergyMay 28, 2025Theresa Passive House, high-performance design, hot-humid climates, residential performance, sustainable design, architectural preservation, energy efficiency, indoor air quality (IAQ), thermal comfort, embodied carbon, responsible materials sourcing, Passive House Institute U.S. (Phius), Phius certification, PHIUS 2018+ Source Zero, ASHRAE Climate Zone 2A, photovoltaic panels, battery backup systems, self-sufficiency, resilience, Forge Craft Architecture + Design, Hugh Jefferson Randolph Architects, Studio Ferme, integrated design process, building envelope, HVAC system, on-site solar panels, MEP (Mechanical, Electrical, Plumbing) engineering, Positive Energy, building science, human-centered design, net-zero energy buildings, heating loads, cooling loads, source energy, airtightness, energy modeling, continuous insulation, thermal bridges, air changes per hour (ACH@50 Pa), air leakage, Blower Door Test, high-performance windows, triple-glazing, low-emissivity (low-e) coatings, Solar Heat Gain Coefficient (SHGC), balanced ventilation, Energy Recovery Ventilators (ERVs), dedicated dehumidification, right-sizing mechanical systems, comfort, health, durability, passive survivability, Winter Storm Uri, University of Texas research, climate-specific standards, moisture management, key performance metrics, site energy use index (EUI), renewable energy production, wall assemblies, water control layer, air control layer, thermal control layer, vapor control layer, wood frame system, mineral wool insulation, unvented roof, Marvin windows, indoor pollutants, combustion products, Volatile Organic Compounds (VOCs), particulate matter (PM2.5), ASHRAE Standard 62.2, ventilation rates, Variable Refrigerant Flow (VRF) heat pump AC, Panasonic Intellibalance 1000 ERV, MERV filtration, heat pump hot water heater, climate resilience, extreme weather events, grid outages, source zero certification, community education, AIA Housing Award, Passive Project of the Year – Retrofit, Austin Green Awards, affordable multifamily housing, building envelope prioritization, mechanical ventilation with energy recovery (ERV) implementation, MEP systems integration, advanced air filtration, MERV ratings, active energy independence, photovoltaics, battery storage, MEP engineer collaboration, climate-specific MEP solutions, commissioning agent

Phius Market Penetration in the US: A Comparative Analysis with Typical Code-Built Houses

The adoption of Phius passive building standards in the United States, while demonstrating a robust upward trend, currently constitutes a small fraction of the overall construction market, which is predominantly characterized by buildings constructed to meet minimum code requirements. Phius certified buildings offer substantial advantages over typical code-built houses, most notably in their superior energy efficiency, which translates to significant reductions in operational energy consumption and associated costs. Furthermore, these high-performance buildings provide enhanced indoor air quality, increased durability, and a greater level of resilience against extreme weather events and power outages. The number of Phius certified projects and the total square footage of these projects have been steadily increasing across the US, reflecting a growing interest in and adoption of these advanced building principles. Moreover, the integration of Phius standards into the energy codes of several states and municipalities indicates a growing recognition of their value in achieving ambitious energy efficiency and sustainability goals. This report aims to provide a comprehensive, data-driven analysis of the current market penetration of Phius standards within the US construction sector, offering a comparative perspective against conventional code-compliant building practices and assessing the implications for the future of sustainable building in the nation.

Code, Building Science, Electrification, Healthy Home, High Performance Homes, HVAC, Phius, Passive HousePositive EnergyMay 26, 2025Phius passive building standards, US construction market, code-built houses, energy efficiency, operational energy consumption, indoor air quality, durability, resilience, extreme weather events, power outages, Phius certified projects, square footage, sustainability goals, Phius certification programs, net-zero energy buildings, continuous insulation, airtight building envelope, high-performance windows and doors, heat- and moisture-recovery ventilation, minimal space conditioning systems, Phius CORE, Phius ZERO, Phius REVIVE 2024, deep energy retrofits, climate-specific standards, US building codes, decentralized regulatory framework, International Code Council (ICC), National Fire Protection Association (NFPA), model building codes, International Energy Conservation Code (IECC), Home Energy Rating System (HERS) Index, ENERGY STAR certification, building permits, single-family homes, multifamily projects, commercial buildings, market penetration of Phius, certification growth trends, energy savings, construction costs, indoor environmental quality, thermal comfort, natural disasters, factors influencing Phius market adoption, regulatory endorsement, decarbonization, training programs, professional certification, long-term cost savings, financial incentives, Qualified Allocation Plans, perceived higher upfront costs, familiarity with passive building principles, specialized materials, traditional construction practices, future outlook for Phius, zero-carbon built environment.

The Resurgence of Natural Building Materials in High-End Homes: A Building Science Perspective for Architects

The landscape of luxury residential architecture is undergoing a profound transformation, driven by an escalating demand for homes that embody both sophisticated elegance and profound environmental responsibility. This evolution is particularly evident in the growing emphasis on sustainable practices, personalization, and a deep, intrinsic connection to the natural world. By the end of this decade, it is anticipated that high-end homes will prominently feature biophilic design principles, seamlessly integrating elements such as optimized natural light, lush indoor gardens, and fluid indoor-outdoor living spaces. This is not merely a passing aesthetic trend but a fundamental redefinition of luxury, where well-being and ecological stewardship are as valued as opulence and exclusivity.

Natural Building Material, Indoor Air Quality, High Performance Homes, Healthy Home, Environmental Design, Code, Building Science, Building Enclosure, Architectural DesignPositive EnergyMay 26, 2025luxury residential architecture, sustainable practices, personalization, environmental responsibility, biophilic design, natural light, indoor gardens, indoor-outdoor living spaces, United Nations Sustainable Development Goals, Paris Agreement, net-zero energy buildings, carbon footprint, eco-friendly building materials, passive design strategies, smart home technologies, personalized climate control, AI-driven systems, sustainable materials, natural building materials, renewable resources, low carbon footprints, recyclability, biodegradability, greenhouse gas emissions, construction waste, energy efficiency, insulation, thermal properties, indoor air quality (IAQ), low-VOC compositions, breathability, durability, organic aesthetic appeal, wellness strategy, building science, building envelopes, moisture management, bulk water, vapor diffusion, air-transported moisture, deflection, drainage, drying, vapor pressure, vapor permeability, dew point, hygroscopic materials, hydrophilic materials, hydrophobic materials, capillarity, hygric buffering, vapor retarders, vapor barriers, cold climates, hot and humid climates, mixed climates, thermal performance, R-value, thermal mass, heat capacity, thermal conductivity, density, specific heat capacity, thermal inertia, air movement, natural ventilation, wind-driven ventilation, stack effect, volatile organic compounds (VOCs), off-gassing, formaldehyde, benzene, toluene, earthen homes, adobe, compressed earth block (CEB), rammed earth, compressive strength, seismic considerations, reinforcement techniques, foundations, moisture barriers, wall protection, code acceptance, hemp-based materials, hempcrete, hemp batt insulation, carbon sink, hemp hurds, lime-based binder, fire resistance, char layer formation, VOC neutralization, structural frame, shear strength, Cross-Laminated Timber (CLT), engineered wood, CNC technologies, load-bearing capabilities, strength-to-weight ratio, acoustic properties, sound absorption, floating floors, charring effect, fire ratings, prefabrication, climate-specific design, structural engineers, building science consultants, skilled professionals.

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