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Posts tagged mold growth
The 5 Principles of a Healthy Home

This blog post will present a foundational framework for architectural practice, emphasizing the profound impact of building design decisions on human health and well-being. Moving beyond conventional priorities of aesthetics and initial construction costs, which are unfortunately all too common and mundane in our modern era, this post introduces and explores "5 Principles of a Healthy Home." These principles offer a holistic approach to achieving superior indoor environmental quality (IEQ) and long-term building durability. By understanding and integrating these foundational building science concepts, architects are empowered to design spaces that actively promote the health, cognitive function, and restorative sleep of occupants, thereby elevating their role to advocates for human thriving.

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Architectural Design, Building Enclosure, Building Science, Dehumidification, Filtration, Healthy Home, High Performance Homes, HVAC, Indoor Air Quality, Mechanical Design, VentilationPositive EnergyBuilding design and human health, indoor environmental quality (IEQ), principles of a healthy home, architects as advocates for human thriving, aesthetics vs. first cost in construction, indoor air quality, structural resilience, occupant well-being, human thriving, time spent indoors, invisible threats in indoor environments, particles, gas-phase pollutants, bioaerosols, physiological functions, cognitive functions, epigenetic changes, prenatal gene regulation, indoor air pollutants and gene expression, impact of air quality on cognitive abilities, decision-making, CO2 levels and cognitive performance, impact of air quality on sleep, particulate matter and nitrogen dioxide, sleep disturbances, building enclosure, moisture transport, water management, deflect, drain, dry principles, water-resistive barrier (WRB), flashing details, air barrier, insulation layer, vapor barrier, air leakage, air movement and water vapor transport, material selection and indoor air quality, toxic air pollutants, flame retardants, formaldehyde, chromated copper arsenate (CCA), lead, polyvinyl chloride (PVC), phthalates, dioxins, isocyanates, crystalline silica, air distribution system, flex duct, duct board, fluid dynamics, metal ductwork, air mixing, pollutant removal, indoor pollutants: particles, gases, particulate matter (PM), PM2.5, PM10, ultrafine particles, volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), bioaerosols: bacteria, viruses, protozoa, fungal spores, archaea, dust mites, active sources of indoor pollutants, cooking, showering, indoor combustion, air fresheners, personal care products, passive emissions, plasticizers, perfluorinated chemicals (PFAS), antimicrobials, six classes of harmful chemicals, dust as a pollutant reservoir, ventilation vs. air leakage, exhausting pollutants, supplying fresh air, ASHRAE Standard 62.1, ASHRAE 62.2, local exhaust: kitchen and bathroom, range hood, CFM (cubic feet per minute), whole-building fresh air, heat recovery ventilators (HRVs), energy recovery ventilators (ERVs), humidity control, excess moisture, mold growth, dimensional instability, VOC emissions, damp environments and health impacts, respiratory issues, 40-60% RH range, energy codes and latent loads, dehumidification needs, vapor compression dehumidifiers, desiccant dehumidifiers, particulate matter filtration, MERV ratings, HEPA filters, active air cleaning technologies, ozone, mechanical filtration.
The Case for Dedicated Dehumidification In Sealed Attics

Modern building design increasingly embraces sealed attic construction as a strategy to enhance energy efficiency and improve air leakage control, particularly beneficial for the performance of HVAC ductwork. This approach, where the attic space is brought within the building's thermal and air control envelope, fundamentally alters the moisture dynamics compared to traditional vented attics. While offering significant advantages, sealed attics introduce unique moisture challenges that demand precise and active management to prevent long-term durability issues and maintain superior indoor air quality.

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Designing Healthier Homes by Eliminating Fossil Gas Appliance Emissions

Architects, as the primary designers of our built environment, hold a profoundly influential position in shaping the health and well-being of building occupants. Beyond the critical considerations of aesthetics, structural integrity, and energy performance, a deep understanding of the invisible forces at play within a building's envelope is increasingly paramount. This report aims to equip architects with the essential knowledge to proactively design for superior indoor air quality (IAQ), particularly concerning emissions from common household gas appliances. The decisions made during the design phase, from material selection to mechanical system integration, directly influence the indoor environment and, by extension, the health outcomes of those who inhabit these spaces. This effectively positions architects as critical guardians of public well-being within the built space, expanding their traditional role to encompass a vital public health responsibility.

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Indoor Air Quality, HVAC, Electrification, Architectural Design, Building Enclosure, Code, Filtration, Healthy Home, High Performance Homes, VentilationPositive EnergyDesigning healthier homes, eliminating fossil gas appliance emissions, indoor environmental quality, architect's role, indoor air quality, gas appliances impact on home health, combustion byproducts, hazardous air pollutants, synthesizing scientific findings, actionable strategies for architectural practice, pollutants emitted by gas appliances, health effects, design and engineering solutions, fundamentals of indoor air quality, source control, ventilation, filtration, temperature and relative humidity levels, building as a dynamic system, geographic site, local climate, physical structure, HVAC, construction techniques, contaminant sources, occupants' activities and behaviors, air exchange pathways, mechanical ventilation systems, infiltration, air pressure differences, building envelope, "Building Tight, Ventilate Right" imperative, energy consumption, pollutant concentration, energy efficiency, ventilation strategies, indoor air pollutants exceed outdoor levels, internal pollutant sources, "concentration trap", managing and removing internal contaminants, key pollutants from gas appliances, nitrogen dioxide, carbon monoxide, particulate matter, volatile organic compounds, moisture, respiratory irritation, asthma exacerbation, infection risk, decreased lung function, fatigue, chest pain, impaired vision, headaches, dizziness, confusion, nausea, DNA damage, mortality, transmission of airborne pathogens, organ damage, allergic reactions, cancer, dampness, mold growth, electric coil burners, high-dose exposure, pulmonary edema, diffuse lung injury, bronchitis, ambient air quality standards, carboxyhemoglobin, unvented gas space heaters, gas stoves, back-drafting, angia, poor ventilation, ultrafine particles, respirable particulate matter, cooking emissions, airborne particles, pathogens, respiratory aerosols, formaldehyde, benzene, unburned natural gas leakage, environmental tobacco smoke, automobile exhaust, sensory irritation, carcinogens, moisture load, human respiration and perspiration, bathing, washing, plants, pets, appliance selection, all-electric homes, electronic ignitions, proper appliance installation and maintenance, ducted range hoods, capture efficiency, airflow requirements, multi-family homes, whole-house ventilation strategies, tighter building envelopes, backdrafting risks, make-up air systems, targeted spot exhaust, bathroom fan, high-efficiency filtration, MERV-13, infectious aerosol exposure, cost-benefit analysis, air cleaning, indoor particle concentrations, semivolatile organic compounds, monitoring and alarms, carbon monoxide alarms, advanced IAQ monitors, PM2.5 sources, collaboration with MEP engineers, certified technicians, health impacts, continuous leakage, moisture byproduct, all-electric transition, building a healthier future, works cited, RMI, ASHRAE, EPA, LBNL, ventilation and air cleaning, envelope leakage, hazardous air pollutant emissions, residential ventilation requirements.
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.

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