Photo of a rigid exterior insulation installed on the roof of a house.

The NorthernSTAR team’s “overcoat” is a continuous air, moisture, and thermal barrier that is applied on the outside of the roof structure for improved overall performance.

Top Innovation Spotlight: Exterior Rigid Insulation Best Practices

For years, Building America research teams have advocated using the thermal, air, and vapor properties of rigid foam sheathing insulation to improve walls, roofs, and foundations of homes. In 2013, these research efforts earned a Top Innovation award, acknowledging work by three Building America teams. Research by the Partnership for Home Innovation resulted in a design methodology for high-performance walls with exterior rigid foam sheathing under wind pressure loading, which will lead to improved disaster-resistant wall solutions. This research formed the basis for a new ANSI Standard for wind pressure resistance, which is now referenced in model building codes across the United States. Building Science Corporation’s field and test facility studies of rigid structure sheathing include: verification of an optimally performing, cost-effective framed wall assembly; use of insulation board as the primary sheathing and in certain areas, as the drainage plane and vapor control layer; and techniques for roof applications. NorthernSTAR Partnership’s whole-house “overcoat” approach to air-sealing and insulating existing homes with rigid foam installed over the roof, walls, and foundations has reduced air leakage by up to 81%. Building Energy Optimization analysis of the strategy indicates source energy savings above 50% and whole-house leakage reductions of 20% to 60% when the roof alone was retrofitted. Learn about all of the Building America Top Innovations.

Building America Website Renovation

You may have noticed that the Building America website is sporting a new look! In addition to the style change, we have enhanced the site with an online newsletter page including current and archived issues, a new Frequently Asked Questions (FAQ) feature, and updated Climate-specific pages with case studies describing whole house solutions for new and existing homes and technologies appropriate for all climate zones. Feedback is encouraged; please send comments to Building America Webmaster.

DOE Challenge Home at 2014 RESNET Conference

The 2014 RESNET Building Performance Conference is the premier national forum on home energy ratings, existing home retrofits, building codes and energy policy. The conference offers strategic options to business challenges and provides a venue where attendees can find usable solutions in an evolving industry. While at RESNET, plan to attend the DOE Challenge Home track, which will outline the business case for building zero energy-ready homes, present builder and rater perspectives and motivations for building in this space, and dig into key technical issues with Building America experts. The DOE Challenge Home track runs from February 24–26, with 10 sessions in all.

DOE Challenge Home Tech Trainings for Zero Energy-Ready Homes

The Challenge Home program continues its series of technical training webinars, which provide overviews of systems critical to performance of zero energy-ready homes. Mark your calendar for these upcoming webinars.

Ducts in Conditioned Space
Date/Time: 3/20/14 – noon-1:30 p.m. Eastern
Presenter: Bill Zoeller, Steven Winter Associates
Description: One of the DOE Challenge Home program’s mandatory specs calls for ducts in conditioned space. However “ducts in conditioned space” isn’t a one-size-fits-all design requirement. During the last several years, DOE’s Building America research program and its partners have worked out the kinks on a toolkit of duct design strategies. In this session Bill Zoeller, a leading Building America expert, will present the pros and cons of these strategies so you can specify distribution systems that are effective in any type of project.

Comprehensive Building Science
Date/Time: 3/26/14 – noon-1:30 p.m. Eastern
Presenter: Dean Gamble, Environmental Protection Agency
Description: DOE Challenge Homes aren’t just really efficient – they’re also designed and built using solid building science principles. Version 3 of the ENERGY STAR® Certified Homes program, a prerequisite for every Challenge Home, delivers three key systems that improve comfort, indoor air quality, and durability—a complete thermal enclosure system, a complete HVAC system, and a complete water management system. In this webinar, Dean Gamble will cover the building science basics that underlie these key systems, and will discuss the top three challenges of each system and how to overcome them.

New Publications from Building America

The Building America Publications Library offers an extensive collection of technical reports, measure and strategy guidelines, case studies, and other resources to help you boost energy efficiency in new and existing homes. Also, the Building America Solution Center links you to expert building science and energy-efficiency information based on Building America research results. Here are samples of some of our most recent publications:

Cladding Attachment Over Thick Exterior Insulating Sheathing
The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of wood framed walls and mass masonry wall assemblies. In this research, Building Science Corporation addressed these questions:
1. What are the relative roles of the mechanisms and the magnitudes of the force that influence the vertical displacement resistance of the system?
2. Can the capacity at a specified deflection be reliably calculated using mechanics-based equations?
3.What are the impacts of environmental exposure on the vertical displacement of furring strips attached directly through insulation back to a wood structure?

Technology Solutions Case Study: Stud Walls With Continuous Exterior Insulation for Factory Built Housing
This case study describes the Advanced Envelope Research effort led by the ARIES team, which will provide factory homebuilders with high-performance, cost-effective alternative envelope designs. In the near term, these technologies will play a central role in meeting stringent energy code requirements. The primary goal of this research is to develop wall designs that meet the thermal requirements based on 2012 IECC standards. Given the affordable nature of manufactured homes, impact on first cost is a major consideration in developing the new envelope technologies.

Evaluating an Exterior Insulation and Finish System for Deep Energy Retrofits
Exterior insulation and finish systems (EIFS) are proprietary synthetic formulations that are applied to the exterior walls of buildings to serve as insulation and exterior cladding. The insulation thickness can vary from less than one inch to a foot or more. In this project, the ARIES team investigated the applicability of EIFS for residential deep energy retrofits through modeling and a case study home. The home was retrofitted using a site-applied four-inch-thick EIFS. Site-specific details were developed as required for the residential retrofit application. Site work and the costs of the system were documented. The demonstration home was modeled using BEopt™ energy and cost analysis software to explore the cost-effectiveness of various EIFS insulation thicknesses in two climate locations.

Additional reports published recently:
Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control
Technology Solutions Case Study: New Insights for Improving the Designs of Flexible Duct Junction Boxes
Hood River Passive House
Evaluation of Retrofit Variable-Speed Furnace Fan Motors
New Whole-House Solutions Case Study: Hydronic Heating Coil Versus Propane Furnace
Advanced Envelope Research for Factory Built Housing, Phase 3—Design Development and Prototyping

Visit the Building America Publications Library to access the entire catalog of publications to help improve the efficiency of new and existing homes.

Want to learn more about Building America or help us spread the word about the program? View the new video, “What is Building America?” on DOE’s YouTube channel to learn about how Building America aims to bridge the gap between homes with high energy costs and homes that are healthy, durable, and energy efficient.

Please forward this announcement to colleagues who may be interested in subscribing to future updates about Building America.