Research Reports

RR-0001: Measurement of Ventilation and Interzonal Distribution in Single-Family Homes by Building Science Corporation — last modified 2008/06/04

Ventilation air change rate, local mean age-or-air, and interzonal ventilation air distribution were measured for two single-family homes and eight ventilation systems. A multi-zone, single-gas, tracer gas decay measurement technique was used. A single-story, slab-on-grade 1350 sq. ft. house was tested in Las Vegas, Nevada, and a two-story, 3192 sq. ft. house with basement was tested in Minneapolis, Minnesota. The ventilation systems studied included various configurations of exhaust, supply, and balanced ventilation, with and without whole-house recirculation by the central heating and cooling air-handler unit fan. Some of the systems were independent of the central air distribution system, while others were integrated with it. In general, results showed that all ventilation systems benefitted from periodic operation of the central fan, giving excellent uniformity of ventilation air distribution. System without central fan recirculation showed poor ventilation air distribution for closed rooms where there was no ventilation system duct.

RR-0002: Practical Approaches to Residential Ventilation for Improved Durability and Indoor Air Quality by Building Science Corporation — last modified 2008/06/11

This presentation examines how to provide durability for little or no incremental cost, as a goal of the Building America program.

RR-0003: An Advanced Systems Engineering Approach to Affordable Single Family Homes by Building Science Corporation — last modified 2008/06/11

This presentation examines the integrated system concepts of advanced framing, air flow retarder system, thermal envelope system, air distribution system and mechanical systems.

RR-0004: Air Barriers vs. Vapor Barriers by Joseph Lstiburek — last modified 2008/06/13

Most of us are not aware of just how differently these two barriers work in building assemblies. This article makes the differences as clear as the polyethylene film that should (or more likely should NOT) be in your walls.

RR-0005: Transfer Grille Sizing by Armin Rudd — last modified 2008/06/12

Sizing information excerpted from “RR-0006: Discussion of the Use of Transfer Grilles to Facilitate Air Flow in Central Return Systems.”

RR-0006: Discussion of the Use of Transfer Grilles to Facilitate Return Air Flow in Central Return Systems by Armin Rudd — last modified 2008/06/12

Transfer grilles represent a cost-effective alternative to individual return ducts if they are properly configured for air flow, privacy, and aesthetics.

RR-0007: Advanced Space Conditioning by Building Science Corporation — last modified 2008/06/18

Everything you ever wanted to know about HVAC for homes-thermal comfort, air distribution, nature of and dealing with contaminants, HVAC strategies, and climate-appropriate graphics to boot.

RR-0008: Time-Based Scheduling of Residential Ventilation by Armin Rudd — last modified 2008/06/24

Discussion of the purposes and practices of residential ventilation.

RR-0009: Wood Shear Panel Behavior and Seismic Design Guidance—Test Results by Building Science Corporation — last modified 2008/07/07

A presentation about wood shear panel behavior and seismic design guidance based on shear panel design testing.

RR-0101a: Moisture, Building Enclosures, and Mold—Part I by Building Science Corporation — last modified 2008/06/11

How water gets into a structure, why it doesn’t leave, and how these architectural flaws become HVAC headaches.

RR-0101b: Moisture, Building Enclosures, and Mold—Part II by Building Science Corporation — last modified 2008/06/11

How water gets into a structure, why it doesn’t leave, and how these architectural flaws become HVAC headaches.

RR-0103: Water Management by Joseph Lstibure — last modified 2008/06/12

This is a concise overview of the principles and steps to follow when dealing with water from the foundation to the roof.

RR-0105: Brick, Stucco, Housewrap and Building Paper by Joseph Lstiburek — last modified 2008/06/13

The manufacturers of housewraps have for years promoted the fantasy that water vapor in wall assemblies only moves one way – from the inside out. So, therefore, walls should be designed to “breathe” outwards. So, therefore, you should buy a highly vapor permeable housewrap. So, therefore, you should buy “our product.”

RR-0106: Problems with Housewraps by Joseph Lstiburek — last modified 2008/06/13

The primary function of a housewrap or building paper is rain penetration control. It is not air infiltration despite what the manufacturers say. The energy aspects of housewraps are vastly overstated. They have been embraced by builders for this function as can be evidenced by their market penetration. Yet their critical role in building durability is under appreciated and not marketed. It has been a triumph of marketing over physics.

RR-0107: Drywall, Wood and Truss Uplift by Building Science Corporation — last modified 2008/06/18

Wood moves. Drywall does not move. Interesting problem. The more you attach drywall to wood, the more cracks you have. Easy, attach the drywall to less wood, and, in a way, that allows the wood to move.

RR-0108: Unvented Roof Systems by Joseph Lstiburek — last modified 2008/06/24

Unvented roof systems can be safely used in many different climates. In cold climates, insulating sheathing must be added exterior to the roof sheathing to prevent condensation on the underside of the roof sheathing.

RR-0109: Sizing and Startup Procedures for Cooling Systems by Armin Rudd — last modified 2008/06/24

High performance building envelopes deserve high performance comfort conditioning systems. Especially for refrigerant based cooling systems, proper sizing and startup procedures are critical.

RR-0110: HVAC Equipment Sizing Strategies: Taking Advantage of High-Performance Buildings by Kohta Ueno — last modified 2008/06/24

If you are going to fine-tune your building enclosure, fine-tuning your HVAC system becomes even more important. This presentation covers everything you need to know to right-size your HVAC for better performance, fewer callbacks, and happier customers.

RR-0111: Placement of Ducts and HVAC Systems in Conditioned Space: An Overview by Kohta Ueno — last modified 2008/06/24

A discussion of the placement of ducts and HVAC equipment inside the conditioned space.

RR-0112: Setting Up Performance and Prescriptive Criteria and Domestic Water Use and Construction Waste Generation by Building Science Corporation — last modified 2008/07/07

There are no national programs with a performance evaluation process for water or for construction waste. These tables provide relative impacts of indoor water conservation measures and construction waste management measures.

RR-0113: Advanced Framing by Building Science Corporation — last modified 2008/07/07

This presentation discusses advanced framing techniques and includes comparisons to conventional framing.

RR-0114: Cutting Through the Clutter—Marketing Program Comparison by Building Science Corporation — last modified 2008/07/07

A short discussion of green building programs and federal initiatives for green building.

RR-0201: Using Wood Efficiently: From Optimizing Design to Minimizing the Dumpster by Building Science Corporation — last modified 2006/12/04

Americans have been building homes with wood—shaping logs, joining timbers, nailing studs—for almost 400 years. Our current approach, stick framing, grew poplular in the mid-1800's because it too less skill, required simpler tools, and took fewer people than timber framing. We apparently really like waste haulers, too.

RR-0202: Basement Insulation Systems by Building Science Corporation — last modified 2006/12/04

Heat loss from basements accounts for a significant portion of the energy loss from a home. In many jurisdictions, basement insulation is a building code requirement. Cost usually determines the type of insulation system used.

RR-0203: Relative Humidity by Building Science Corporation — last modified 2008/06/11

What relative humidity should I have in my home? Seems like a simple enough question. However, the answer can sometimes be difficult to understand. Elevated relative humidity at a surface – 70 percent or higher - can lead to problems with mold, corrosion, decay and other moisture related deterioration. When relative humidity reaches 100 percent, condensation can occur on surfaces leading to a whole host of additional problems. An elevated relative humidity in carpet and within fabrics can lead to dust mite infestation and mildew (mildew is mold growing on fabrics).

RR-0204: Practical and Effective Approaches to Residential Ventilation for Production Builders by Building Science Corporation — last modified 2008/06/11

This presentation examines durability with respect to moisture, and how mechanical ventilation can be used to control it.

RR-0205: Moisture Control for Buildings by Building Science Corporation — last modified 2008/06/11

When designing a building’s envelope and its interaction with the mechanical system, temperature, humidity, rain and the interior climate often are ignored. The focus for the building may be more on aesthetics and cost than on performance.

RR-0206: Foundations—Moisture Resistant Construction by Joseph Lstiburek — last modified 2008/06/12

Builders for many years have put mechanical equipment and ducts in non-living spaces such as crawls and attics primarily to save valuable floor space. Be that as it may (there are lots of good reasons for having this equipment in conditioned spaces, GIVEN proper attention to ventilation and pressurization issues), it makes perfect sense to condition these areas, for a variety of energy, moisture and durability reasons.

RR-0207: Residential Ventilation and Latent Loads by Joseph Lstiburek — last modified 2008/06/13

Adding outdoor air in hot, humid climates causes moisture problems, right? The answer is sometimes. It all depends on the condition of the house before outdoor air is added. In fact, most houses in hot, humid climates are over-ventilated due to duct leakage and induced air change from internal air pressure effects.

RR-0208: What You Need to Know About Mold by Joseph Lstiburek — last modified 2008/06/18

This article answers your questions about mold, what it is, where it grows, how it spreads, how can I prevent it.

RR-0209: Mold Testing by Building Science Corporation — last modified 2008/06/18

Although this article is titled "Mold Testing" it actually tells you why testing for mold is usually not needed.

RR-0210: Mold Remediation in Occupied Homes by Building Science Corporation — last modified 2008/06/18

This article provides both general guidelines for mold remediation as well as specific guidelines for the typical locations where mold is most often found in houses.

RR-0211: Mold—Causes, Health Effects and Clean-up by Building Science Corporation — last modified 2008/06/18

This article briefly repeats some of the information in the other mold articles but also includes information on how to prevent mold in residential structures.

RR-0212: PV Primer by Building Science Corporation — last modified 2008/06/18

PV systems have come a long way in the last two decades. While they may not work for all homes, residential installations are becoming a practical reality under more and more conditions. Here are the nitty-gritty details of photovoltaic systems. The details are meant to “de-mystify” both the technology and its economics.

RR-0213: Combo Space/Water Heating Systems—"Duo Diligence" by Building Science Corporation — last modified 2008/06/19

Combo systems use a gas water heater to provide domestic water and space heating. Find out when its appropriate to use such a system and guidelines for doing it right.

RR-0214: Conditioning Air in the Humid South—Creating Comfort and Controlling Cost by Building Science Corporation — last modified 2008/06/19

An examination of five different systems that show how to cool and dehumidify inside air while maintaining sufficient introduction of outside air for ventilation efficiently and cost-effectively.

RR-0215: Dehumidification Systems Research Results by Armin Rudd — last modified 2008/06/24

Moisture is the number one enemy of the durability of a house. Installing controlled mechanical supply ventilation systems, and dehumidification separate from cooling for humid climates is one of the ways to insure durability with respect to moisture.

RR-0216: Special Topics on Residential HVAC by Armin Rudd — last modified 2008/06/24

Discussion of cyclical trade-offs between building envelope improvements, reduced system size, and more efficient systems.

RR-0217: Building America Pilot Program—Guaranteed Resource- & Energy-Efficiency Now by Building Science Corporation — last modified 2008/06/24

A performance-based industry collaborative program in which energy, water, and maintenance guarantees can be translated into home buyer savings. The guarantees drive product performance, market demand, and environmental benefit. Collaboration among a wide variety of industry players ensures that the shared benefits of such a bold initiative outweigh the shared risks.

RR-0218: Green Building Programs—An Overview by Building Science Corporation — last modified 2008/07/07

An article discussing six green building programs with brief descriptions of USGBC’s residential programs.

RR-0301: Unvented Roof Summary Article by Building Science Corporation — last modified 2008/06/11

This article was written to tie together and summarize the various papers on unvented conditioned cathedralized attics found on our website. We realize that there is a wealth of information, and much of it too detailed to understand or digest in a single sitting. Furthermore, building officials might not have the time available to carefully examine the many documents on the page; this is meant to summarize the main arguments, and provide pointers to where detailed information and measured data can be found.

RR-0302: Roof and Attic Ventilation Issues in Hot-Humid Climates by Building Science Corporation — last modified 2008/06/11

A presentation examining the requirement for roof/attic venting in hot-humid climates.

RR-0303: Ventilation and Air Leakage by Building Science Corporation — last modified 2008/06/11

Buildings leak water and air, which is normal and unavoidable. Therefore, designers should not fixate on preventing leakage, i.e. making buildings “airtight.” Because even if all cracks were sealed, buildings have doors and windows.

RR-0304: Central Fan Integrated Supply Ventilation—The Basics by Armin Rudd — last modified 2008/06/13

The simplest, most effective, and most economical way to introduce fresh air in homes with central forced air systems is to use the central fan to pull in and distribute a controlled amount of outside air.

RR-0305: Why It's So Important (and Troubling) to Keep Ducts and Equipment in Conditioned Space by Building Science Corporation — last modified 2008/06/13

Perhaps the single most challenging BSC performance for Building America production homebuilders is that all ducts and HVAC equipment must be within the conditioned space (this means no ducts in outside walls and no ducts or air handlers in garages, vented attics or vented crawlspaces). It’s an important and even driving element for each of the four case studies in this report.

RR-0306: Unvented Roofs, Hot-Humid Climates, and Asphalt Roofing Shingles by Building Science Corporation — last modified 2008/06/13

When constructing unvented roofs with asphalt shingles in hot-humid climates, a vapor barrier must be installed between the asphalt shingles and the roof deck.

RR-0307: Windows and Occupant Comfort by Building Science Corporation — last modified 2008/06/18

How windows are part of a high performance wall system and what that means to the occupants.

RR-0308: Renovating Your Basement by Building Science Corporation — last modified 2008/06/18

Heat loss through uninsulated basement walls can account for up to one-third of the heat loss from an average home. Installing insulation on basement walls is often inexpensive, easy to accomplish and frequently combined with “finishing the basement.”

RR-0308: The How and Why of Your High Performance HVAC System by Building Science Corporation — last modified 2008/06/18

Concise explanation of how a high performance HVAC system works in a high performance home.

RR-0310: EcoVillage Homeowner Handbook by Building Science Corporation — last modified 2008/06/19

After a high performance home has been designed, constructed, and commissioned, what ensures that the home is actually operated at peak performance? It takes just 24 easy-reading pages for the homeowner to learn just how simple it is to achieve the full benefits of these particular energy-efficient, comfortable, healthy, and durable homes.

RR-0311: Optimizing Wood Framing by Building Science Corporation — last modified 2008/07/08

A discussion of the combination of factors that have driven up our consumption of wood in home building and how to break the myths about optimized framing techniques.

RR-0401: Conditioned Crawl Space Construction, Performance and Codes by Building Science Corporation — last modified 2006/11/27

This paper discusses the differences between vented, unvented and conditioned crawl spaces. Best practice construction techniques and assemblies for conditioned crawl spaces are discussed, the results of a field monitoring program are presented, and the code language addressing crawl spaces is explained.

RR-0402: Singing the "blues" in the key of "low-e" by Building Science Corporation — last modified 2008/06/11

High performance compact fluorescent lighting (CFLs) is not just about energy savings; it’s also about the other aspects of performance such as color rendering.

RR-0403: Air Barriers by Building Science Corporation — last modified 2008/06/11

Air barriers are systems of materials used to control airflow in building enclosures. They typically completely enclose the air within a building .The physical properties which distinguish air barriers from other materials are the ability to resist air flow and air pressure.

RR-0404: Roof Design by Building Science Corporation — last modified 2008/06/11

Roofs can be designed and constructed to be either vented or unvented in any hygro-thermal zone. Air barrier systems are typically the most common approach, however, air pressure control approaches are be-coming more common especially in cases involving remedial work on existing structures. Vapor diffusion should be considered as a secondary moisture transport mechanism when designing and building roofs. Specific vapor retarders are often unnecessary if appropriate air movement control is provided or if control of condensing surface temperatures is provided.

RR-0405: Community-Scale Evaluation Results by Building Science Corporation — last modified 2008/06/11

Using four Building Science Consortium Building America community-scale projects, this paper investigates the nature, strength, and durability of connections between high performance dwellings and developments. There are few inherent or natural links between the two (particularly in the production home setting); the connections must be either imposed (by government entities) or created in the marketplace. Because communities often involve two very distinct players—the developer and the builders—and the project often spans up to 10 years, it is challenging to develop and sustain either an imposed or marketed system with strong and meaningful links between high performance homes and neighborhoods.

RR-0406: Face Sealed vs. Drainable EIFS by Joseph Lstiburek — last modified 2008/06/12

Exterior insulation and finishing systems (EIFS) are inherently defective and unfit of use as an exterior cladding system where moisture sensitive components are used without a provision for drainage or in locations and assemblies without adequate drying.

RR-0407: Installing a Window with Building Paper on OSB over Wood Frame Wall by Joseph Lstiburek — last modified 2008/06/12

Details on how to install a window using building paper as the drainage plane

RR-0408: The deKieffer Bypass by Building Science Corporation — last modified 2008/06/13

Construction practices have improved and the HVAC systems need to improve with them. The deKieffer Bypass relieves air pressure in rooms without compromising sound or light transmission.

RR-0409: Painting by Building Science Corporation — last modified 2008/06/18

Exposure to sunlight (ultraviolet radiation) and moisture are the major factors affecting the durability of paint coatings and the durability of the substrate.

RR-0410: Vapor Barriers and Wall Design by Building Science Corporation — last modified 2008/06/19

Good design and practice involve controlling the wetting of building assemblies from both the exterior and interior and different climates require different approaches.

RR-0411: Vent on Venting by Building Science Corporation — last modified 2008/06/19

Just about everyone in the building industry can be guilty of using building terms loosely, and a prime example is with attics, roof assemblies. Just so that we are all on the same page.

RR-0412: Insulations, Sheathings and Vapor Retarders by Building Science Corporation — last modified 2008/06/19

Two seemingly innocuous requirements for building enclosure assemblies bedevil builders and designers almost endlessly: keep water vapor out, let the water vapor out if it gets in. It gets complicated because, sometimes, the best strategies to keep water vapor out also trap water vapor in.

RR-0413: The Snapshot—A Quick Description by Building Science Corporation — last modified 2008/06/19

SNAPSHOT stands for Short, Non-destructive Approach to Provide Significant House Operation Thresholds. It is a test form used in the Building America program to ascertain house performance and specifications.

RR-0414: The Anderson/Sargent Dallas Show House: A Case Study by Building Science Corporation — last modified 2008/07/08

A presentation discussing the U.S. Department of Energy’s Building America Zero Energy Home in Dallas, Texas.

RR-0501: Guide to Insulating Sheathing by Building Science Corporation — last modified 2006/12/04

This document looks at methods of incorporating insulating sheathing into the design of wall assemblies. Through examining and understanding the various material properties, these properties can then be used to our advantage in the design of water management details, vapor control strategies, and increased thermal resistance in wall assemblies.

RR-0502: Review of Residential Ventilation Technologies by Building Science Corporation — last modified 2006/12/04

This paper reviews current and potential ventilation technologies for residential buildings with particular emphasis on North American climates and construction.

RR-0503: Rainwater Management Performance of Newly Constructed Residential Building Enclosures by Building Science Corporation — last modified 2007/03/06

Building Science Corporation was engaged by the Home Builders Association of Metro Orlando and the Florida Home Builders Association to review the performance of residential assemblies in the central Florida (Orlando) area during the three hurricanes in August and September 2004.

RR-0504: Integrating Systems for Green Design by Building Science Corporation — last modified 2008/06/11

The effects of building development on the environment are at the most basic level about durability. Building a house or community is really about the durability of people, the durability of buildings, and the durability of the planet. Durability is really another way of expressing the concept of sustainability to the building community.

RR-0505: Residential Dehumidification Systems Research for Hot-Humid Climates by Building Science Corporation — last modified 2008/06/11

Twenty homes were tested and monitored in the hot-humid climate of Houston, Texas, U.S.A., to evaluate the humidity control performance and operating cost of six different integrated dehumidification and ventilation systems that could be applied by production homebuilders. Fourteen houses, that also met measured energy efficiency criteria, had one of the six directly- or indirectly-integrated dehumidification and ventilation systems. Three reference houses had the same energy efficiency measures and controlled mechanical ventilation, while three other reference houses met code minimums for energy efficiency and did not have mechanical ventilation.

RR-0506: Vapor Permeance Chart by Building Science Corporation — last modified 2008/06/13

Good design and practice involve controlling the wetting of building assemblies from both the exterior and interior and different climates require different approaches. This chart lists some common vapor permeance characteristics.

RR-0507: Affordable Housing—Toward Zero Energy by Betsy Pettit — last modified 2008/06/19

A presentation discussing zero energy homes, affordable housing and the available technologies to reach zero energy.

RR-0508: Understanding Green Homes & Durability by Betsy Pettit — last modified 2008/06/19

Presentation discussing the systems integration approach to energy efficient, durable, sustainable homes.

RR-0509a: Details for Mold-Free Homes by Betsy Pettit — last modified 2008/06/19

A presentation discussing the causes of house failures due to mold.

RR-0509b: Details for Avoidance of Mold—Foundations by Betsy Pettit — last modified 2008/06/19

A presentation discussing the details for building a dry foundation.

RR-0509c: Renovating Existing Basements by Betsy Pettit — last modified 2008/06/19

A presentation discussing the details for renovating existing basements.

RR-0509d: Crawlspaces by Betsy Pettit —