Posts tagged building science principles

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.

Understanding "Ping Pong Water" and Navigating Attic Moisture Dynamics in Modern Roof Assemblies

The design of residential attics has undergone a significant transformation. Conventionally, attics were vented spaces with thermal insulation placed on the attic floor, separating the unconditioned attic from the conditioned living space below. However, contemporary building practices increasingly favor unvented, or "conditioned," attics where insulation is applied directly to the underside of the roof deck.[1] This shift is driven by several factors, including the desire to bring HVAC equipment and ductwork within the building's thermal and air barrier envelope to improve system efficiency and longevity, enhance overall building airtightness for energy savings, and create potentially usable conditioned or semi-conditioned space within the attic volume.[3]

Building Enclosure, Building Science, Dehumidification, HVAC, High Performance Homes, Healthy Home, Code, Architectural DesignPositive EnergyMay 23, 2025"Ping Pong Water" phenomenon, attic moisture dynamics, modern roof assemblies, unvented attics, conditioned attics, moisture control challenges, roof sheathing moisture, attic ventilation, airtightness, energy efficiency, solar radiation, thermal buoyancy, hygric buoyancy, OSB hygroscopicity, chemical potential of wood, sorption isotherms, hysteresis, OSB and mold susceptibility, roof assembly durability risks, sheathing degradation, rot, corrosion of metal components, "bound water, " climate zone dependence, spray polyurethane foam (SPF), open-cell SPF (ocSPF), closed-cell SPF (ccSPF), vapor permeability, air barrier qualities, water barrier, code requirements, active attic conditioning, supply air strategies, return air strategies, dedicated dehumidification, exterior insulation, vapor diffusion ridge vents, fibrous insulation assemblies, cellulose, fiberglass, mineral wool, air tightness, vapor control layer, hybrid insulation systems, architect design considerations, building science principles, interior humidity management, material compatibility, constructability, quality control, building codes, hygrothermal modeling, risk management, lifecycle costs.

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