Engineering Commons^™

Mitigation Of Airborne Contaminant Spread Through Simple Interventions In An Occupied Single-Family Home, Florida Solar Energy Center, Nazim Muradov

FSEC Energy Research Center®

Historically, reducing aerosol-based transmission of respired viruses in indoor environments has been of importance for controlling influenza viruses and common-cold rhinoviruses. The present public health emergency associated with SARS-CoV-2 makes this topic critically important. Yet to be tested is the potential effectiveness of simple interventions that create an isolation zone (IZ) for a suspected/confirmed sick or sensitive person requiring quarantine. The intent in existing homes is to find a practical means to mitigate exposure to airborne contaminants. In creating an IZ in an occupied single-family home in the study, four simple strategies were tested. The test configurations were: (1) IZ …

Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes, Florida Solar Energy Center, Tanvir Khan

FSEC Energy Research Center®

Existing evidence strongly suggests that viral infectious diseases can be transmitted via an airborne route across distances in indoor environments. Accordingly, the risk of airborne transmission within homes should be managed. The public health emergency associated with SARS-CoV-2 makes controlling airborne transmission of respired viruses in indoor environments critical, especially in poorly ventilated indoor environments. The effectiveness of engineering interventions requiring minor efforts that create a negative-pressure isolation zone (IZ) for a contagious person has yet to be tested for existing residential homes.

To mitigate the risk of airborne virus transmission and maximize health protection for the population in existing …

Lab Home Testing Of Residential Isolation Space Control To Minimize Infectious Disease Transmission In Existing Single-Family Homes -- Fact Sheet, Florida Solar Energy Center, Tanvir Khan

FSEC Energy Research Center®

The FSEC Energy Research Center at the University of Central Florida performed research to test the effectiveness of interventions to isolate an ill person recovering from a contagious disease in a single-family home from the rest of the occupants in the home. Focus was placed on interventions requiring minor cost and effort on the part of the occupants.

DOE/GO-102021-5537, https://www.nrel.gov/docs/fy21osti/79519.pdf

Ventilation & Masks: Reducing Airborne Transmission Of Covid-19 In A Classroom, Eric A. Schiff

SyracuseCoE Research Brief Series

We've calculated the number of COVID-19 infections that will be spread from a single COVID-19 "superspreader" to students and teachers in a classroom shared for 4 hours in different ventilation and masking conditions.

Residential Attic Performance Comparison Research, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

This research project evaluated cooling energy and moisture-related impacts between conventional attic venting and sealed attic vents in a lab home located in central Florida. All tests had R30 insulation on the ceiling and the roof deck uninsulated. A total of four different test configurations were tested. The four tested configurations were: Attic Vented with Attic Ducts, Attic Vents Sealed with Attic Ducts, Attic Vented with Indoor Ducts, and Attic Vents Sealed with Indoor Ducts. On average the impact from sealing attic vents will increase annual cooling energy use in a Florida home between 5%-10%. For a 1620 square foot …

Evaluating Moisture Control Of Variable-Capacity Heat Pumps In Mechanically Ventilated, Low-Load Homes In Climate Zone 2a, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

The well-sealed, highly insulated building enclosures constructed by today's home building industry coupled with efficient lighting and appliances are achieving significantly reduced heating and cooling loads. These low-load homes can present a challenge when selecting appropriate space-conditioning equipment. Conventional, fixed-capacity heating and cooling equipment is often oversized for small homes, causing increased first costs and operating costs. Even if fixed-capacity equipment can be properly specified for peak loads, it remains oversized for use during much of the year. During these part-load cooling hours, oversized equipment meets the target dry-bulb temperatures very quickly, often without sufficient opportunity for moisture control. The …

Ozone Removal Efficiency And Surface Analysis Of Green And White Roof Hvac Filters, Omed A. Abbass, David Sailor, Elliott T. Gall

Mechanical and Materials Engineering Faculty Publications and Presentations

Heating, ventilation, and air-conditioning ( HVAC ) system filters from a commercial building were tested for their ability to remove ozone from intake air. Filters were taken from rooftop HVAC systems installed for two months: one located on a white membrane roof and the other on a vegetated green roof. One new, unused filter sample was tested as a reference. Samples from these filters were exposed to ozonated air streams at 40 and 120 ppb and relative humidity levels of 30% and 70%. Filter surfaces were analyzed with a scanning electron microscope to observe the structure and composition of the …

Field And Laboratory Testing Of Approaches To Smart Whole-House Mechanical Ventilation Control, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

Whole-house mechanical ventilation is a critical component to a comprehensive strategy for good indoor air quality (IAQ). However, due to lack of integration with standard heating and cooling systems, and perceptions from a portion of the homebuilding industry about risks related to increased energy use, increased cost, and decreased comfort, voluntary and code-required adoption varies amongst regions. Smart ventilation controls (SVC) balance energy consumption, comfort, and IAQ by optimizing mechanical ventilation operation to reduce the heating and/or cooling loads, improve management of indoor moisture, and maintain IAQ equivalence according to ASHRAE 62.2.Suggested Citation:Martin, E.; Fernaughty, K.; Parker, D.; Lubliner, M.; …

Residential Performance Code Methodology For Crediting Dehumidification And Smart Vent Applications Final Report, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

As energy efficiency reduces the hours where air conditioning is called for, and as codes require outdoor air to be brought into homes, humidity levels in homes may rise to the point where dehumidification is required. However, there are currently no standards in Florida's Energy Conservation Code for dehumidification. Thus, a mechanical contractor that invests in an expense such as variable speed heat pumps or heat pipe technology in order to dehumidify and save energy receives little benefit relative to another home that installs an inefficient dehumidifier. A reference home dehumidification strategy needs to be established.Another strategy to reduce interior …

Comparative Performance Of Two Ventilation Strategies In A Hot-Humid Climate, Florida Solar Energy Center, Sarah Widder

FSEC Energy Research Center®

ASHRAE Standard 62.2, 'Ventilation and Indoor Air Quality in Low-Rise Buildings,' is the most commonly referenced residential ventilation standard in the United States. It is currently required by ENERGY STAR Version 3 (V3), the 2012 International Energy Conservation Code, the U.S. Department of Energy's Zero Energy Ready Home Program, many state weatherization programs, and many other home performance programs. The standard calls for ventilation levels that are perceived by some builders and contractors to cause indoor moisture issues in hot-humid climates unless mitigated by supplemental dehumidification systems, which increase overall energy consumption. Therefore, many high-performance home builders in a hot-humid …

Energy-Efficient Management Of Mechanical Ventilation And Relative Humidity In Hot-Humid Climates, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

The U.S. Department of Energy's Building America research team Building America Partnership for Improved Residential Construction conducted this research project to gain data and insight into these issues. The project focused on energy-efficient management of mechanical ventilation and RH during the cooling season. It consisted of eight test configurations. A particular focus evaluated how well a ductless seasonal energy-efficiency ratio (SEER) 21.5 mini-split heat pump (MSHP) could perform as the primary cooling system without a dehumidifier for supplemental dehumidification in a continuously mechanically ventilated house.

Flexible Residential Test Facility: Impact Of Infiltration And Ventilation On Measured Cooling Season Energy And Moisture Levels (2016), Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Originally published in January 2014, this revision of the report clarifies and corrects references to Standard 62.2 as the 2013 version (62.2-2013), and it corrects the total CFM requirement for the subject buildings under the standard. Further, two plots have been updated to distinguish between the mechanical CFM and the total CFM required for the subject buildings under Standard 62.2-2013.

Investigation Of The Effectiveness And Failure Rates Of Whole-House Mechanical Ventilation Systems In Florida, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

This report presents the results of a field investigation of the effectiveness and failure rates of whole-house mechanical ventilation systems installed in Florida homes over the last 15 years. The report includes homeowner survey and ventilation system testing results and code modification recommendations based on study findings.

Developing Exhaust Air Energy Recovery Credits For The Florida Energy Code, Florida Solar Energy Center, Bereket Nigusse

FSEC Energy Research Center®

Energy recovery ventilator (ERV) or Heat Recovery Ventilator (HRV) devices recover energy from building's exhaust air to precondition outdoor air. Energy savings of ERV/HRV devices were determined for various commercial buildings in Florida climate using whole building energy simulation tool. The annual HVAC energy percent savings due to ERV/HRV device were calculated from HVAC energy use of a standard reference building without and with ERV/HRV device using EnergyPlus. The annual HVAC energy savings potential (ERV Credits) will be used for code compliance calculation when a compliance software does not have ERV modeling capability. The ERV/HRV credits were reported by building …

A Review Of Home Airtightness And Ventilation Approaches For Florida Building Commission Research, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

This research project was conducted with the primary objectives of 1) providing a literature review, examination of experimental data, and calculations of energy impacts of using or not using various types of ventilation systems and 2) developing alternative approaches to achieving acceptable levels of ventilation while avoiding the risks associated with super-tight home enclosures and potential mechanical system failures. The report includes discussions of pertinent airtightness and mechanical ventilation topics and provides recommended ventilation practices for Florida.

Assessment Of Energy Efficient Methods Of Indoor Humidity Control For Florida Building Commission Research, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

This research project was conducted with the primary objective to identify approaches and technologies which can achieve energy-efficient latent cooling in light of code requirements that may increase overall ventilation rates in new Florida homes. This report covers the work of two primary efforts of completing a literature review and testing a few space conditioning methods in a mechanically ventilated building. Results from a literature review provide a list of various approaches to managing the latent load in homes with emphasis on energy efficiency and cost-effectiveness. In addition to a literature review, controlled experiments using four different approaches to space …

Flexible Residential Test Facility: Impact Of Infiltration And Ventilation On Measured Cooling Season Energy And Moisture Levels, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Air infiltration and ventilation in residential buildings is a very large part of the heating loads, but empirical data regarding the impact on space cooling has been lacking. Moreover, there has been little data on how building tightness might relate to building interior moisture levels in homes in a hot and humid climate. To address this need, BA-PIRC has conducted research to assess the moisture and cooling load impacts of airtightness and mechanical ventilation in two identical laboratory homes in the hot-humid climate over the cooling season.

Impact Of Residential Mechanical Ventilation On Energy Cost And Humidity Control, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

The DOE Building America program has been conducting research leading to cost effective high performance homes since the early 1990's. Optimizing whole house mechanical ventilation as part of the program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this white paper is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version …

Flexible Residential Test Facility: Impact Of Infiltration And Ventilation On Measured Heating Season Energy And Moisture Levels, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Perhaps no residential topic has been discussed as much among building scientists as air infiltration and required mechanical ventilation. Usually, envelope tightening is recommended as an efficiency strategy for retrofitting an existing home. In humid climates, reducing infiltration can reduce summer moisture loads. However, during drier weather when the air conditioner is not running, lower infiltration can lead to potential condensation. Even though severe cold weather is rare in the Deep South, the prevalence of single-pane windows can lead to condensation events.

Numerical Simulation Of Buoyancy-Driven Turbulent Ventilation In Attic Space Under Winter Conditions, Shimin Wang, Zhigang Shen, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Attic design and construction have significant impacts on residential buildings’ energy performance. In order to understand how passive ventilation rates affect ridge-vent attic’s performance, a two-dimensional steady-state finite volume model is employed to simulate the buoyancy-driven turbulent ventilation and heat transfer in a triangular attic space of a gable-roof residential building under winter conditions. The modeled attic has a pitch of 5/12 and a passive ventilation system, consisting of continuous ridge and soffit vents. The v2f model is used to analyze the turbulent air flow and natural convection heat transfer inside the attic. The effects of ambient air temperature, vent …

Building America Industrialized Housing Partnership (Baihp Ii), Annual Report - Budget Period 4 (Bp4), January 01, 2009 - December 31, 2009, Florida Solar Energy Center, Robert Abernethy

FSEC Energy Research Center®

This annual report summarizes the work conducted by the Building America Industrialized Housing Partnership (BAIHP - www.baihp.org) during the fourth budget period (BP4) of our contract, January 1, 2009 to December 31, 2009. Progress from the three previous budget periods is included for context.

BAIHP is led by the Florida Solar Energy Center (FSEC) of the University of Central Florida. With over 50 Industry Partners including factory and site builders, work was performed in four task areas:

• Task 1: System Evaluations
• Task 2: Prototype House Evaluations
• Task 3: Community Scale Evaluations
• Task 4: Post- Phase 3 Activities.

In Task 1, …

An Overview Of Building America Industrialized Housing Partnership (Baihp) Activities In Hot-Humid Climates, Florida Solar Energy Center, Subrato Chandra

FSEC Energy Research Center®

BAIHP (www.baihp.org ) conducts systems research and technical assistance activities for new housing. Hot-humid climate efforts described here include:

Systems research: NightCool – A hybrid cooling and dehumidification strategy employing radiative cooling and desiccant materials. Interior Duct Systems in Manufactured Houses – Tests are ongoing in an occupied prototype home in Alabama and the FSEC manufactured housing lab. Ventilation and Dehumidification – A new strategy has been developed to hook up a whole-house dehumidifier so that it only runs when the air conditioning compressor is off. Plug Load Reduction – Whole house feedback devices and security system based plug load …

Energy Impacts Of Various Residential Mechanical Ventilation Strategies, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

The Building America program has been working with home builders for more than a decade using a variety of strategies for bringing fresh air into the homes. Many of these strategies utilize the central air handler fan from the HVAC system to ventilate when the system runs. Controllers can be purchased to force the air to enter for minimum periods of time or to shut off outside air dampers after some period of runtime. EnergyGauge USA, a detailed hourly residential simulation program, has been modified to simulate the various runtime strategies, as well as supply- or exhaust-only ventilation strategies and …

Balanced Return Air, Duct Airtightness, And Combustion/Dilution Air Code Compliance In 40 Central Florida Homes, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

This report has been extracted from a larger report titled "Florida Building Code - Enhance Florida's Building to Next-Generation Energy & Mechanical Codes and Enrich Compliance", FSEC-CR-1678-06, November 29, 2006, which can be found at http://www.fsec.ucf.edu/en/publications/pdf/FSEC-CR-1678-06.pdf

Assessing Six Residential Ventilation Techniques In Hot And Humid Climates, Florida Solar Energy Center, Neil Moyer

FSEC Energy Research Center®

The addition of mechanical ventilation air to "tight" homes in hot and humid climates may adversely impact health, building durability, comfort and energy use by raising indoor humidity levels (RH) above 50%. High indoor humidity has been linked to microbial growth, building material decay, discomfort, and increased energy use (Moyer, et al, 2001). High indoor humidity in "tight" homes with mechanical ventilation has been documented in various Building America projects in hot humid locations (Rudd 2003).

The research described here quantifies the energy use, and humidity impacts of six mechanical ventilation strategies installed serially in a new, Energy Star Manufactured …

Standards For Clean Air Florida Homes, Florida Solar Energy Center, Subrato Chandra

FSEC Energy Research Center®

These standards are designed for new, slab on grade homes built in Florida. Changes to the standards may be necessary for other house construction types. These standards are not meant to be exclusionary. The home builder may submit alternative materials or design details which will result in equivalent performance. These standards complement all building codes and do not supersede any codes.

Performance And Impact From Duct Repair And Ventilation Modifications Of Two Newly Constructed Manufactured Houses Located In A Hot And Humid Climate, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Two nearly identical houses situated next to each other in Bossier City, Louisiana were studied in an effort to better understand moisture and cooling energy related problems in manufactured houses with low thermostat set-points during the cooling season. By design, the major difference between houses was the type of air conditioning units. House A had a standard split air conditioner and House B had a two-speed split air conditioner.

In an effort to make the buildings more similar, the building airtightness was adjusted until it was the same in each house, and duct leaks were sealed so that the ducts …

Evaluation Of Energy Efficient Improvements To Portable Classrooms In Florida, Florida Solar Energy Center, Michael Callahan

FSEC Energy Research Center®

Florida has over 25,000 portable classrooms in use around the state. Energy costs for these structures exceed $20 million a year - or about 11% of all energy-related expenditures for educational facilities. Research has also shown interior ventilation rates in these classrooms typically fall far below the recommended levels in ASHRAE Standard 62-1989.

To explore ways in which costs might be reduced and the physical learning environment improved, we conducted a two year experiment in two highly instrumented portable classrooms at Silver Sands Middle School in Volusia County. A series of retrofits, aimed to cut energy use and improve ventilation …

Comparative Summer Attic Thermal Performance Of Six Roof Constructions, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Florida Solar Energy Center (FSEC) has measured summer attic thermal performance of six roofs at a heavily instrumented test site, the Flexible Roof Facility (FRF). The FRF is a 1,152 square foot (107 m2) building with six roof adjacent test cells which are heavily insulated from each other. Some 233 channels of data were obtained; this includes twenty temperature measurements per cell, extensive meteorological conditions, surface and tower wind speeds and attic humidity and roof surface moisture accumulation. The data were collected over the ASHRAE definition of summer (June - September) to compare cooling season thermal of roofing systems. Six …

Ventilation, Humidity, And Energy Impacts Of Uncontrolled Airflow In A Light Commercial Building, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

A small commercial building was monitored before and after energy saving retrofits to study the impact of retrofits upon ventilation rates, humidity, building pressure and air conditioning energy use. Duct airtightness testing identified severe duct leakage as a significant source of uncontrolled airflow. Differential pressure and infiltration measurements using tracer gas indicated an attic exhaust fan as another significant source of uncontrolled airflow. Duct repair resulted in a 31% drop (30.5 kWh/day) in cooling energy, and an increase in relative humidity from 72% to 76%. Turning off the attic exhaust resulted in an additional 36% energy savings (14.3 kWh/day), including …