High-Performance Building Retrofit Options


Project Motivation

Retrofits and renovations are an essential, ever-evolving tool in reducing energy consumption in US buildings, particularly older structures. Recent advances in building technology have significantly expanded the options available to homeowners, while manufacturing improvements have made cutting-edge elements more affordable than ever.

As the availability of energy-efficient systems and materials increases, seeing how they work in real-world situations -- and with one another -- becomes increasingly crucial. Working on behalf of the US Department of Energy, CSE researchers examined two elements in particular: high-performance windows, which minimize heat losses and gains within a building, and vacuum insulation panels (VIPs), a novel insulation material with very low thermal conductivity. 

Proving Durability and Cost-Effectiveness

Following an extensive analysis of the existing structure, CSE's research teams began the process of retrofitting a 1950s slab-on-grade building with new high-efficiency windows and exterior insulation. The main purpose of this retrofit was to prove that high-efficiency windows and vacuum insulation panels could significantly improve the energy performance of old wood-framed buildings in a northern US climate, while simultaneously being durable and cost-competitive retrofit options. To this end, CSE's teams developed a way to integrate high-performance windows with VIP insulation to minimize thermal shorts and long-term durability problems.

Using sensors and other on-site measuring equipment, CSE researchers monitored overall energy consumption, humidity and temperatures along the building envelope for the best part of a year. CSE's findings not only confirmed the insulation value of the VIPs, but also identified potential issues with leakages and air circulation.

First in the U.S. Commercial Wall Retrofit, Using Vacuum Insulation

In 2013, Fraunhofer CSE partnered with the Midcoast Regional Redevelopment Authority in Brunswick, ME, Dow Corning, and Dryvit on two Department of Energy (DOE) Building Technologies Office (BTO)-funded projects. They were focused on a field demonstration of the viability in the Northern Climate zone (both from a constructability and energy performance perspective) of a new high efficiency Vacuum Insulated Panel (VIP) system. This technology was developed earlier by Dow Corning and Dryvit under the DOE BTO ARRA funding. In addition to the high R-value wall retrofit, the scope of the project also included the replacement of existing windows with high efficiency windows manufactured by Mathews Brothers of Belfast, Maine. The research team collaborated to increase the thermal performance of exterior insulation and finishing systems (EIFS) to reach R-40 performance, meeting the needs for high performance walls. Additionally, the project helped remove barriers to using EIFS on retrofit commercial buildings desiring highly insulated wall assemblies.


Dr. Jan Kośny
Director, Building Enclosures and Materials
Office +1 (617) 714-6525