Engineering Commons^™

Survey Of Unvented Attics In Climate Zone 2a, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

Moisture risk must be managed in unvented attics to ensure durability of components and longevity of the system. The FSEC Energy Research Center (FSEC), at the University of Central Florida tested and collected data in six homes in the northern Florida portion of IECC Climate Zone 2A built after 2015 with unvented (semi-conditioned) attics to add to the body of knowledge on the accumulation of moisture in the attic and its effects on roof moisture that can impact durability.

Measured Energy And Moisture Performance Impacts From Vented And Unvented Attic With Insulation On Top Of Ceiling In The Hot Humid Climate Zone, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Sealing attic vents helps decrease house air leakage and may reduce some moisture issues in attics in hot humid climates. new code-approved unvented attics can use different types of insulation materials, however, there are specific requirements that vary by materials used and climate zone. These requirements may be complex and may increase construction and operational energy costs.

This paper was published in the 2020 ACEEE Summer Study on Energy Efficiency in Buildings.

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 …

Nightcool: A Nocturnal Radiation Cooling Concept, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An experimental evaluation has been conducted on a night sky cooling system designed to substantially reduce space cooling needs in homes in North American climates. The system uses a sealed attic covered by a highly conductive metal roof (a roof integrated radiator) which is selectively linked by air flow to the main zone with the attic zone to provide cooling - largely during nighttime hours. Available house mass is used to store sensible cooling. Currently, the system's capability for solar dehumidification with minimal electricity input is demonstrated.

Energy Efficient Renovations Of Storm Damaged Residences - Florida Case Studies, Florida Solar Energy Center, Neil Moyer

FSEC Energy Research Center®

Storm-damaged homes offer the opportunity for repairs that reduce energy use, improve comfort and enhance resistance to future storms. Case studies of four Florida homes damaged in the summer of 2004 were documented to show the costs and benefits of various retrofit strategies. All four homes required roof replacement and each took advantage of roof cladding with higher reflectance than the original, a proven means of reducing cooling energy use. Two of the case studies included improvements to attic insulation, tightening of the envelope and/or duct system and improved efficiency equipment and lighting. Energy savings attributable to storm repairs were …

Technical Support For Development Of An Attic Simulation Model For The California Energy Commission, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The California Energy Commission (CEC) is developing a new attic simulation model for assessing residential energy performance within its Title 24 residential compliance methodology. Within this project, we are providing technical support to assist Bruce Wilcox and CEC in development of the model based on Florida Solar Energy Center (FSEC) experience with similar models. We assisted the effort by using data from FSEC instrumented facilities to help verify the eventual simulation. We also outlined critical issues for modeling with the development of the simulation. Given the importance of attic ventilation, we are also conducting new studies of varied ventilation rates …

Flexible Roofing Facility: 2004 Summer Test Results, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The Flexible Roof Facility (FRF) is a test facility in Cocoa, Florida designed to evaluate five roofing systems at a time against a control roof with black shingles and vented attic (Figure E-1). Since 1989 the testing has evaluated how roofing systems impact summer residential cooling energy use and peak demand. In the summer of 2004, the following roofing systems were tested. Materials tested were: Galvalume® unfinished (unpainted) 5-vee metal with vented attic (3rd year of exposure), galvanized unfinished 5-vee metal with vented attic (3rd year of exposure, black shingles with standard attic ventilation (Control Test Cell), white standing seam …

Literature Review Of The Impact And Need For Attic Ventilation In Florida Homes, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The Florida Department of Community Affairs (DCA) is seeking to examine the impact and necessity of residential attic ventilation in Florida homes. Here, we provide technical support by examining existing data sources on the impacts of attic ventilation both on cooling and heating energy use as well as to attic and home moisture levels. In particular we evaluate the issues with sealed attic construction where the attic is unvented and expanded foam insulation is applied directly to the underside of the roof decking.

We also report the data from Florida Solar Energy Center (FSEC) instrumented facilities to add unique information …

Theoretical Evaluation Of The Nightcool Nocturnal Radiation Cooling Concept, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An evaluation has been conducted of the potential of a night sky cooling system to substantially reduce space cooling needs in homes in North American climates. The report describes the innovative residential cooling system which uses nocturnal night sky radiation from a roof integrated radiator. The system uses a sealed attic covered by a highly conductive metal roof which is selectively linked by air flow to the main zone with the attic zone to provide cooling- largely during nighttime hours. Available house mass is used to store sensible cooling. Additional dehumidification is done during the evening hours as warranted by …

Flexible Roofing Facility: 2003 Summer Test Results, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The Flexible Roof Facility (FRF) is a test facility in Cocoa, Florida designed to evaluate five roofing systems at a time against a control roof with black shingles and vented attic (Figure E-1). The testing evaluates how roofing systems impact summer residential cooling energy use and peak demand. In the summer of 2003, the following roofing systems were tested: Galvalume® unfinished 5-vee metal with vented attic (2nd year of exposure); sealed attic with proprietary configuration; high reflectance brown metal shingle with vented attic; galvanized unfinished 5-vee metal with vented attic (2nd year of exposure); black shingles with standard attic ventilation …

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.

Comparative Evaluation Of The Impact Of Roofing Systems On Residential Cooling Energy Demand In Florida, Florida Solar Energy Center, John Sherwin

FSEC Energy Research Center®

Roof and attic thermal performance exert a powerful influence on cooling energy use in Florida homes. The Florida Power and Light Company and the Florida Solar Energy Center instrumented six side-by-side Habitat homes in Ft. Myers, Florida with identical floor plans and orientation, R-19 ceiling insulation, but with different roofing systems designed to reduce attic heat gain. A seventh house had an unvented attic with insulation on the underside of the roof deck rather than the ceiling: (RGS) Standard dark shingles (control home); (RWB) White "Barrel" S-tile roof; (RWS) Light colored shingles; (RWF) White flat tile roof; (RTB) Terra cotta …

Performance Assessment Of Photovoltaic Attic Ventilator Fans, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Controlling summer attic heat gain is important to reducing air conditioning energy use in homes in hot-humid climates. Both heat transfer through ceilings and to attic duct systems can make up a large part of peak cooling demand. Attic ventilation has long been identified as a method to abate such heat gains. We present test results from using the photovoltaic (PV) attic ventilator fans in a test home to assess impact on attic and cooling energy performance.

Energy And Resource Assessment Of The Caribbean Marine Research Center, Lee Stocking Island, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A project is being coordinated by the Florida Solar Energy Center (FSEC) with the Perry Foundation and the Caribbean Marine Research Center (CMRC) on Lee Stocking Island in the Bahamas. The purpose of the research is to demonstrate energy and water savings associated with efficient technologies in an isolated sub-tropical climate. The project is being used as a test case to examine how energy and resource independent eco-tourism projects might be successfully accomplished in Florida and other Caribbean locations.

FSEC plans to monitor energy and water consumption in two buildings at the center. The VIP (Scientists' quarters) building has been …

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 …

Monitored Summer Peak Attic Air Temperatures In Florida Residences, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Florida Solar Energy Center (FSEC) has analyzed measured summer attic air temperature data taken for some 21 houses (three with two different roof configurations) over the last several years. The analysis is in support of the calculation within ASHRAE Special Project 152P which will be used to estimate duct system conductance gains which are exposed to the attic space. Knowledge of prevailing attic thermal conditions are critical to the duct heat transfer calculations for estimation of impacts on residential cooling system sizing.

The field data was from a variety of residential monitoring projects which were classified according to intrinsic differences …

A Stratified Air Model For Simulation Of Attic Thermal Performance, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An improved computer simulation model for attics has been developed. The model accounts for detailed radiation, buoyancy and wind driven air flows and thermal stratification within the attic airspace. Through comparison with measured data, the paper examines the relative importance of the various modeling parameters and assumptions upon simulation accuracy. Stratification of the attic air was found to be a critical modeling characteristic which is typically ignored in building energy simulations. Both model and measurement results shows that air stratification increases significantly when low-emittance surfaces are included.

Rbs Technology: Task 3 Report, Florida Solar Energy Center, Philip Fairey

FSEC Energy Research Center®

The purpose of this report is to discuss the current state of attic radiant barrier system (RBS) technology. Concepts, research issues and experimental test results are presented and discussed.

Radiant Barriers: A Question And Answer Primer, Florida Solar Energy Center, Philip Fairey

FSEC Energy Research Center®

Attic radiant barriers made of aluminum foil are becoming a popular way for homeowners to save energy and money in Southern states. They are increasing in popularity for two reasons. First, tests by the Florida Solar Energy Center and other groups show that they work. Second, manufacturers are improving the quality of radiant barrier materials.

To most homeowners, attic radiant barriers are a new energy conservation concept; many of them have questions about how radiant barriers work and how to use them. This Energy Note answers some of the most commonly asked questions. It also recommends ways to install radiant …