Reports

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-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-0601: Analysis of Indoor Environmental Data by Building Science Corporation — last modified 2006/12/04

This summary and analysis of indoor temperature and humidity data has been collected over a three and a half year period from 43 houses located mostly in the hot, humid gulf coast region.

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-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-0603: Impact Resistance of Advanced Framed Wall Systems with Insulating Sheathing as the Primary Sheathing by Building Science Corporation — last modified 2007/02/19

Advanced framed wall systems that use that use a stud spacing of 24 inches on center and eliminate the plywood or OSB sheathing from the wall and replace it with insulating sheathing is a type of enclosure assembly that has been designed to be energy efficient combined with efficient material use. The purpose of this research program was to determine the impact resistance performance of advanced framed wall systems with insulating sheathing as the primary sheathing from wind blown debris. With no standards available for testing wall assemblies, a window industry standard ASTM E1886-05 and E1996-05 Missile Level D, Wind Zone 1 and Wind Zone 2 Enhanced Protection and Wind Zone 3 Basic Protection Standard was adopted was used as a starting point for the research. The testing demonstrated two surprising outcomes: 1. None of the walls passed at an impact velocity of 50 fps including the ½” OSB wall, and 2. The high performance wall assembly (1” of insulating sheathing, housewrap, and 2 inches of closed cell spray foam installed in the cavity space) out-performed the baseline house (framed wall with 1/2” OSB sheathing) at a slightly reduced impact velocity of 43fps. These results indicate that high performance wall assemblies provide equivalent or even better impact performance then standard wall assemblies.

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-0701: Whole House Ventilation Systems Options by Building Science Corporation — last modified 2007/10/18

 

RR-9401: Development of Moisture Storage Coatings for Enthalpy Storage Wallboard by Building Science Corporation — last modified 2008/06/04

Two moisture-storage coating mixtures developed and tested between late 1990 and early 1991 could provide a low-cost, building-integrated method of managing indoor humidity in hot and humid climates. Since there are large surface areas of interior gypsum wallboard in nearly all new houses, the effort centered around coatings that could be applied to those surfaces.

RR-9301: Phase-Change Material Wallboard for Distributed Thermal Storage in Buildings by Building Science Corporation — last modified 2008/06/04

Development and testing were conducted for a prototype phase-change material (PCM) wallboard to enhance the thermal energy storage capacity of buildings with particular interest in peak load shifting. Most important, it was determined that small-scale differential scanning calorimetry can adequately predict (within 9%) the performance of PCM wallboard when installed in full-scale applications.

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-9801: Vented and Sealed Attics in Hot Climates by Building Science Corporation — last modified 2008/06/04

Sealed attic construction, by excluding vents to the exterior, can be a good way to exclude moisture-laden outside air from attic and may offer a more easily constructed alternative for air leakage control at the top of residential buildings. However, the space conditioning energy use and roof temperature implications of this approach have not been extensively studied. A computer modeling study (Rudd 1996) was performed to determine the effects of sealed residential attics in hot climates on space conditioning energy use and roof temperatures.

RR-0702: Monitored Indoor Moisture and Temperature Conditions in Hot-Humid US Residences by Building Science Corporation — last modified 2008/06/04

Indoor moisture and temperature conditions and equipment operation were measured and analyzed for 43 homes in warm-humid and mixed-humid climate regions of the United States. A range of house and mechanical system types were evaluated, including standard building enclosures and cooling systems and high-performance building envelopes with enhanced cooling or supplemental dehumidification systems. Conventional cooling systems in standard houses usually provide reasonable humidity control (below 60% RH) in midsummer. However, high humidity levels are observed at times when cooling loads are modest. The addition of continuous mechanical ventilation to standard houses is humid climates did not consistently increase indoor humidity levels. Indoor humidity levels were highest in high-performance, low sensible heat gain homes with mechanical ventilation. In these homes, the temperature balance point is higher, so there are many hours when sensible cooling is not required yet there are still significant moisture loads from internal sources and ventilation. These homes often require a separate dehumidifier to maintain space humidity in the swing seasons and at night when the thermostat is satisfied. The use of supplemental dehumidification in a high-performance house enables the implementation of efficiency improvements that significantly reduce sensible cooling demand while still maintaining proper humidity levels.

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-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-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-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-9908: Design Methodology and Economic Evaluation of Central-Fan-Integrated Supply Ventilation Systems by Building Science Corporation — last modified 2008/06/11

Residential ventilation systems can be categorized as supply, exhaust, or balanced systems. This effort focused on establishing a design methodology for central-fan-integrated supply ventilation systems. Air flow measurements were taken for 7.6 m lengths of 12.7 cm through 22.9 cm diameter flexible ducts, with a 15.2 cm wall-cap, at duct pressures of -10 Pa to -120 Pa. Using these measurements and field experience, a five-step method was developed as a guide for sizing and installing the ventilation system. An economic evaluation was made by conducting hourly computer simulations to determine the impact on heating, cooling, and fan energy use for four U.S. climates. An effective ventilation system can be achieved using a filtered duct from out doors to the return side of a central air distribution fan with a specialized fan control that automatically cycles the fan if the fan has been inactive for a period of time.

RR-9907: Measured Air Change Rates and Distribution Ventilation Air in a Single Family Home by Building Science Corporation — last modified 2008/06/11

A single-story, single-family, 1350 ft2house located in Las Vegas, NV was outfitted with two separate ventilation systems. The systems were independent of each other, and were operated at different times to evaluate the relative difference in air change rate and distribution of ventilation air induced by their operation.

RR-9906: Air Handler Leakage Testing: Sierra Air Conditioning, Las Vegas, NV by Building Science Corporation — last modified 2008/06/11

Duct leakage is a concern in the HVAC field, due to energy consumption, pressure balance problems, bypassing of the filter by leakage air, and contaminant draw from unconditioned spaces. Therefore, certain energy efficiency programs set duct leakage performance requirements that must be met to enter the program. However, the overall duct system tightness is limited by leakage at the air handler.

RR-9904: Unvented-cathedralized attics: Where we've been and where we're going by Building Science Corporation — last modified 2008/06/11

Current work is focusing on the performance and durability of unvented-cathedralized attics in hot-humid climates with both tile and asphalt shingle roofing. The advantages for the hot-humid climate are expected to be even greater than for the hot-dry climate.

RR-9905: Air Pressure and Building Envelopes by Building Science Corporation — last modified 2008/06/11

Understanding the significance of the complex flow and pressure distribution problems created by the interaction of the building envelope with the mechanical system and climate can lead to changes in building design, commissioning, operations, maintenance, diagnostics and rehabilitation.

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-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-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-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-9802: Performance of Building America Initiative Houses with Unvented Attics and Tile Roofs Constructed by Pulte Homes, Las Vegas Division by Building Science Corporation — last modified 2008/06/11

A residential attic model, contained in the finite element computer program FSEC 3.0, was empirically aligned with measured attic data from three roof research facilities in Florida and Illinois. This model was then used to simulate hourly space conditioning energy use, and roof and attic temperatures, for peak cooling days and annual weather, for Orlando, Florida and Las Vegas, Nevada. Results showed that, when compared to typically vented attics with the air distribution ducts present, sealed cathedralized attics (i.e. unvented attic with the air barrier and insulation at the sloped roof plane) can be constructed without an associated energy penalty in hot climates.

RR-9902: Mold Control in Publicly Funded Housing Developments by Building Science Corporation — last modified 2008/06/11

This presentation examines health related building problems in public housing.

RR-9903: House and Barn Renovation by Building Science Corporation — last modified 2008/06/11

Building a house or community is really about the durability of people (health, safety and well being of people), the durability of buildings (the useful service life of a building is typically limited by its durability), and the durability of the planet (the well being of the local and global environment).

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-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-9302: Humidity Control in the Humid South by Building Science Corporation — last modified 2008/06/11

Humidity concerns in the southern humid climates are particularly difficult to resolve. This is because one of the most effective approaches to dealing with humidity in heating climates, ventilation, can cause major humidity problems in the humid south. The issue becomes even more complex when you realize that you can replace the word humidity in the previous sentences with the words "indoor air quality " and not change the meaning or impact. Dilution is often used as the solution to indoor pollution in heating climates. Unfortunately, in humid, air conditioning climates, the greater the rate of dilution, ventilation or air change, the greater the rate of moisture entry with the exterior air. Therefore, the greater the likelihood of mold and other biological growth problems, particularly if the moisture in this incoming air is not removed.

RR-9402: Establishing Priorities for the Design of Affordable, Environmentally Responsible Housing in Dallas, Texas, a Mixed Climate Zone by Building Science Corporation — last modified 2008/06/11

Twelve affordable, healthy, environmentally responsible single family houses were designed and built on an urban infill in Dallas, Texas. They will sell for under $80,000 each, making them affordable to families earning less than 80 percent of the median income in the Dallas metropolitan area (under $35,000). Monthly payments will range between $500 to $700 per month. Utility costs (heating, cooling, and hot water) are expected to be $30 per month. Typical utility costs for houses of similar size in Dallas have ranged Between $80 and $100 per month. The building system design resulted in a 60- to-70 percent reduction in energy consumption. A minimum of $50 per month for utility cost will be saved.

RR-9701: Measurement of Attic Temperatures and Cooling Energy Use in Vented and Sealed Attics in Las Vegas, Nevada by Building Science Corporation — last modified 2008/06/11

Traditionally, building codes have required that attics of residential buildings be vented. The ventilation requirement varies between one square foot of net free ventilation area per 300square feet of attic floor area (1:300) to one square foot per 150 square feet (1:150). In cold climates, the primary purpose of attic ventilation is to maintain a cold roof temperature to avoid ice dams created by melting snow, and to vent moisture that moves from the conditioned space to the attic. In cooling dominated climates, the primary purpose of attic ventilation is to vent hot air, heated by solar gain on the roof, thus reducing the cooling load contribution from the roof. The magnitude of the roof cooling load contribution is often in the area of ten percent of the total cooling load for an occupied house.

RR-9901: Air Distribution Fan and Outside Air Damper Recycling Control by Building Science Corporation — last modified 2008/06/11

Energy efficient homes are inherently airtight and require ventilation for acceptable indoor air quality. Recognizing this fact, two building code jurisdictions, the federal department of Housing and Urban Development and the State of Washington, require mechanical ventilation for homes. The state of Minnesota will soon enact regulations for mechanical ventilation in homes, and it is expected that this trend will continue. Of all the options currently available, the low cost and low maintenance central-fan-integrated ventilation approach is the most acceptable to large production builders and manufactured home producers. In this approach, fresh air is filtered and ducted to the return air side of the central system fan. The central system fan and ducts then distribute the ventilation air throughout the living space. This is a resource and energy efficiency strategy that utilizes the existing air ducts and the normal cycling of the fan, in response to demand from the thermostat, to distribute ventilation air and conditioned air at the same time. The patented AirCycler™ control can be used to automatically operate the fan if the fan has been inactive for a period of time, and to control a motorized outside air damper to limit the intake of ventilation air independent of fan operation.

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-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-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-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-0602: Field test of room-to-room uniformity of ventilation air distribution in two new houses by Building Science Corporation — last modified 2008/06/12

In order for dilution ventilation systems to provide predictable results independent of the geometry of individual homes, outside air must be uniformly distributed throughout the house. The primary purpose of this field test was to characterize the uniformity of room-to-room ventilation air distribution under various operating conditions by examining multi-zone tracer gas decay curves and calculating local age-of-air.

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-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-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-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-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-9909: Drainage Planes and Air Spaces by Joseph Lstiburek — last modified 2008/06/12

Every exterior cladding system needs an air space and drainage plane for performance and durability. This article presents the right materials and spaces for most exterior claddings—brick, stucco, and wood, metal and vinyl lap siding.

RR-9910: Wood Durability by Building Science Corporation — last modified 2008/06/12

“We have accepted that design and construction must be responsive to varying seismic regions, wind loads and snow loads. Yet we typically ignore temperature, humidity, rain and the interior climate.” This article puts the durability of wood in the proper context—the environmental context in which we ask it to perform.

RR-9911: Heating Choices by Joseph Lstiburek — last modified 2008/06/12

Based on Building America experience, this report is about selecting furnaces, water heaters, both or sometimes just one to accomplish both space heating and domestic hot water.

RR-9912: Discussion of Ventilation System Energy Performance and Cost by Armin Rudd — last modified 2008/06/12

An hourly simulation stuffy using DOE2.1E was conducted to determine the annual difference in energy consumption between various ventilation options in different climates.

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-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-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-9913: Case Studies in Resource-Efficient Residential Building—The Building America Program by Building Science Corporation — last modified 2008/06/13

Building America is a program of the U.S. Department of Energy, in which teams of architects, engineers, builders, equipment manufacturers, and others collaborate in a systems engineering approach to produce homes that use up to 50 percent less energy to operate.

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