Posts tagged ASHRAE standards

Marfa Ranch

The Marfa Ranch is a distinguished residential project by Lake Flato Architects, is thoughtfully situated on a low rise within the expansive, pristine desert grasslands of Marfa, Texas. This unique location, nestled between the Chihuahuan Desert and the majestic Davis Mountains, presents a challenging yet profoundly beautiful environment. The architectural design of the ranch consciously adopts a low profile, comprising eight distinct structures meticulously organized around a central courtyard. This layout, shaded by native mesquite trees, serves as a cool respite from the sun-drenched desert beyond its walls, drawing inspiration from the area's earliest regional architectural traditions. Architect Bob Harris of Lake Flato articulated that the design embodies a "deliberate quality of spareness that matches the qualities of the land," emphasizing the importance of the house maintaining a low profile to merge seamlessly with the terrain while simultaneously opening to distant views and providing crucial protection from the region's harsh winds and intense sun. This project has garnered significant recognition, including the 2022 Texas Society of Architects Design Award and its inclusion in Dezeen's Top 10 Houses of 2022.

Architectural Design, Building Enclosure, Building Science, Environmental Design, Healthy Home, High Performance Homes, HVAC, Indoor Air Quality, Mechanical Design, Natural Building Material, VentilationPositive EnergyMay 28, 2025Marfa Ranch architecture, applied building science, Chihuahuan Desert environment, Lake Flato Architects, residential project design, courtyard layout, regional architectural traditions, low profile design, Bob Harris (Lake Flato), spareness of design, Texas Society of Architects Design Award, Dezeen Top 10 Houses of 2022, climate-responsive architecture, vernacular architecture, thermal mass, passive cooling, rammed earth walls, modern building science, MEP engineering, building envelope consultants, Positive Energy (MEP firm), human-centered design, healthy spaces, comfortable spaces, resilient spaces, building envelope, MEP systems, integrated design approach, thermal mass definition, specific heat capacity, diurnal temperature ranges, thermal lag, R-value, moisture resilience, Portland cement stabilization, compressive strength, longevity of rammed earth, hydrophobic additives, drainage, slab edge, moisture management, thermal conductivity, moisture content, hygric buffering, density of rammed earth, thermal lag hours, compressive strength of rammed earth, lifespan of rammed earth, R-value of insulated rammed earth, rammed earth wall performance attributes, air barrier, air pressure differences, energy loss prevention, moisture issues prevention, interstitial condensation, indoor air quality, controlled ventilation, mechanical ventilation, Energy Recovery Ventilators (ERVs), Indoor Air Quality (IAQ) definition, IAQ impacts on health, IAQ pollutants (particulate matter, VOCs, combustion byproducts), ASHRAE standards, green-certified buildings, cognitive function, passive building strategies, ventilation strategies, filtration strategies, humidity control strategies, source control strategies, MERV rating, whole-house fresh air systems, local exhaust systems, humidity range, low-VOC materials, combustion safety, holistic MEP design, hydronic heating system, VRF heating/cooling system, resilient design, sustainable water management, water scarcity, groundwater contamination, water conservation, greywater capture, onsite water storage, adaptive reuse (water tank to pool), rainwater collection, building science principles, durable wall assemblies, Energy Recovery Ventilators (ERVs) for IAQ, early collaboration between architects and engineers, healthier buildings, resilient buildings, positive Energy's mission, Kristof Irwin

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.

Building Science, Architectural Design, Building Enclosure, Dehumidification, Healthy Home, Filtration, High Performance Homes, HVAC, Indoor Air Quality, Mechanical DesignPositive EnergyMay 23, 2025Sealed attics, dedicated dehumidification, moisture control, energy efficiency, indoor air quality, HVAC systems, air leakage, building durability, condensation risks, mold growth, air barrier, thermal barrier, insulation, roof deck temperature, building codes (IRC), ASHRAE standards, unconditioned attics, conditioned attics, psychrometrics, vapor control, duct performance, latent load, sensible load, building science principles, dew point, hygric buffering, controlled ventilation, air sealing, maintenance issues, cross-contamination, volatile organic compounds (VOCs), pests, allergens, duct leakage, system strain, pressure balancing, wood framing, sheathing, building envelope, resilience, sustainability, dehumidifier sizing, condensate management, building science experts, MEP engineering.

Breathing Easy: The Case for a National Indoor Air Quality Code in the United States

The United States faces a significant, yet largely unregulated, public health challenge: the quality of the air inside its buildings. Americans spend approximately 90% of their time indoors , breathing air that can be two to five times, and occasionally more than 100 times, more polluted than outdoor air. Despite this reality, the nation lacks a comprehensive federal code specifically governing indoor air quality (IAQ), relying instead on a fragmented system of state regulations, voluntary guidelines, and limited occupational standards. This regulatory gap results in inconsistent protection and contributes to a silent epidemic of health problems—ranging from asthma and allergies to cardiovascular disease, cognitive impairment, and cancer—and imposes a substantial economic burden through healthcare costs and lost productivity, estimated in the tens to hundreds of billions of dollars annually.

CodePositive EnergyMay 1, 2025Indoor Air Quality (IAQ), national IAQ code, public health, building codes, regulations, ventilation, filtration, source control, pollutants, health effects, respiratory illnesses, allergies, cardiovascular disease, cognitive impairment, economic burden, healthcare costs, lost productivity, EPA recommendations, ASHRAE standards, WHO guidelines, implementation challenges, legislative action, phased implementation, research, workforce development, public-private partnerships, Clean Air Act, National Ambient Air Quality Standards (NAAQS), Model Clean Indoor Air Quality Act (MCIAA), California Title 24, Occupational Safety and Health Administration (OSHA), General Duty Clause, Particulate Matter (PM), Volatile Organic Compounds (VOCs), carbon monoxide (CO), radon, nitrogen dioxide (NO2), ozone (O3), formaldehyde, mold, biological contaminants, asthma, COPD, sick building syndrome, structural codes, fire codes, electrical codes, plumbing codes, information asymmetry, market efficiency, negative externalities, energy efficiency, MERV 13 filters, monitoring protocols, maintenance, schools, healthcare facilities, workplaces, cost-benefit analysis, financial assistance, tax incentives, utility programs, stakeholder engagement, building industry, public health advocates, labor unions, environmental organizations, consumer advocacy groups, government agencies, international models, European Union, Canada, South Korea, Japan, Singapore, air changes per hour, carbon dioxide (CO2) sensors, commissioning, verification, education, public awareness campaigns.

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