Water Management of Noninsulating and Insulating Sheathings: Final Report

There is an increasing market in liquid (or fluid) applied water management barriers for residential applications that could be used in place of tapes and other self-adhering membranes if applied correctly, especially around penetrations in the enclosure. This report discusses current best practices, recommends ways in which the best practices can be improved, and looks at some current laboratory testing and testing standards

Hygric Redistribution in Insulated Assemblies: Retrofitting Residential Envelopes Without Creating Moisture Issues

The Building America program has recognized that most of the current housing stock is in need of energy related retrofits. One of the best ways of reducing the space conditioning energy consumption is to improve the thermal performance of the enclosure by adding exterior board foam insulation. This report quantifies the amount of water that can become trapped in the drainage cavity of typical wall systems, and measures the effect of water trapped in the drainage cavity on the moisture content of the sheathing. This study also attempts to explain the discrepancy between hygrothermal simulations and field performance of low permeance, low R-value exterior insulation (e.g. 3/4-in. foil faced polyisocyanurate) in cold climates

Measure Guideline. Hybrid Foundation Insulation Retrofits

This measure guideline provides recommendations for designs and variations for retrofit hybrid assemblies in improving interior foundation insulation and water management of basements. Variations include closed cell spray foam (ccSPF) with membrane waterproofing or air gap membrane drainage layers, rigid board foam insulation at flat walls (cast concrete or CMU block), a 'partial drainage' detail making use of the bulk water drainage that occurs through the field of a rubble stone wall, and non-drained spray foam assemblies (including slab insulation)

Moisture and Structural Analysis for High Performance Hybrid Wall Assemblies

This report describes the work conducted by the Building Science Corporation (BSC) Building America Research Team's 'Energy Efficient Housing Research Partnerships' project. Based on past experience in the Building America program, they have found that combinations of materials and approaches---in other words, systems--usually provide optimum performance. No single manufacturer typically provides all of the components for an assembly, nor has the specific understanding of all the individual components necessary for optimum performance

Evaluation of an Open-Nucleus Model for Forest Tree Breeding

Papers and abstracts from the 27th Southern Forest Tree Improvement Conference held at Oklahoma State University in Stillwater, Oklahoma on June 24-27, 2003

Application of Spray Foam Insulation Under Plywood and Oriented Strand Board Roof Sheathing

Unvented roof strategies with open cell and closed cell spray polyurethane foam insulation sprayed to the underside of roof sheathing have been used since the mid-1990's to provide durable and efficient building enclosures. However, there have been isolated moisture related incidents reported anecdotally that raise potential concerns about the overall hygrothermal performance of these systems. The incidents related to rainwater leakage and condensation concerns. Condensation concerns have been extensively studied by others and are not further discussed in this report. This project involved hygrothermal modeling of a range of rainwater leakage and field evaluations of in-service residential roofs using spray foam insulation. All of the roof assemblies modeled exhibited drying capacity to handle minor rainwater leakage. All field evaluation locations of in-service residential roofs had moisture contents well within the safe range for wood-based sheathing. Explorations of eleven in-service roof systems were completed. The exploration involved taking a sample of spray foam from the underside of the roof sheathing, exposing the sheathing, then taking a moisture content reading. All locations had moisture contents well within the safe range for wood-based sheathing. One full-roof failure was reviewed, as an industry partner was involved with replacing structurally failed roof sheathing. In this case the manufacturer's investigation report concluded that the spray foam was installed on wet OSB based on the observation that the spray foam did not adhere well to the substrate and the pore structure of the closed cell spray foam at the ccSPF/OSB interface was indicative of a wet substrate

Water Management of Noninsulating and Insulating Sheathings: Final Report

There is an increasing market in liquid (or fluid) applied water management barriers for residential applications that could be used in place of tapes and other self-adhering membranes if applied correctly, especially around penetrations in the enclosure. This report discusses current best practices, recommends ways in which the best practices can be improved, and looks at some current laboratory testing and testing standards

Moisture Control Handbook: New, low-rise, residential construction

Moisture problems are prevalent all over North America, almost independent of climate. They are viewed as one of the single largest factors limiting the useful service life of a building. Elevated levels of moisture in buildings also can lead to serious health effects for occupants. Until recently, very little consensus on moisture control existed in the building community. The information available was typically incomplete, contradictory, usually limited to specific regions, and in many cases misleading. A need to develop a document which presented the issues relating to moisture from a building science or ``systems`` approach existed. This handbook attempts to fill that need and illustrates that energy-efficient, tight envelope design is clearly part of the solution to healthy buildings when interior relative humidity, temperature, and pressure are controlled simultaneously. The first three chapters of the handbook present the basic principles of moisture problems and solutions in buildings. Chapter 1 -- Mold, Mildew, and Condensation, examines surface moisture problems. Chapter 2 -- Moisture Movement, examines how building assemblies get wet from both the exterior and interior. Chapter 3 -- Wetting and Drying of Building Assemblies, introduces the concepts of acceptable performance, moisture balance, and the redistribution of moisture within building assemblies. Chapters 4 through 6 apply the concepts outlined in the previous chapters and present specific moisture control practices for three basic US climate zones. The advantages and disadvantages of several wall, foundation, and roof assemblies are discussed for each climate zone

Hygric Redistribution in Insulated Assemblies: Retrofitting Residential Envelopes Without Creating Moisture Issues

The Building America program has recognized that most of the current housing stock is in need of energy related retrofits. One of the best ways of reducing the space conditioning energy consumption is to improve the thermal performance of the enclosure by adding exterior board foam insulation. This report quantifies the amount of water that can become trapped in the drainage cavity of typical wall systems, and measures the effect of water trapped in the drainage cavity on the moisture content of the sheathing. This study also attempts to explain the discrepancy between hygrothermal simulations and field performance of low permeance, low R-value exterior insulation (e.g. 3/4-in. foil faced polyisocyanurate) in cold climates

Moisture and Structural Analysis for High Performance Hybrid Wall Assemblies

This report describes the work conducted by the Building Science Corporation (BSC) Building America Research Team's 'Energy Efficient Housing Research Partnerships' project. Based on past experience in the Building America program, they have found that combinations of materials and approaches---in other words, systems--usually provide optimum performance. No single manufacturer typically provides all of the components for an assembly, nor has the specific understanding of all the individual components necessary for optimum performance