About Us +
Researchers in the Building Technology & Urban Systems Division (BTUS) at Lawrence Berkeley National Laboratory develop data and technologies that increase energy efficiency and improve the health, safety and comfort of building occupants, in the United States and worldwide.

We work closely with industry partners, academics and government officials to achieve these goals, and share our research widely
Research +
We are at the forefront of cutting-edge research that redefines building technology and explores all areas of urban systems.

We have been leaders for decades in developing energy-efficient windows, improving indoor air quality, coming up with new ideas to fix the nation's electricity grid, and so much more.

Visit our research areas at the right to find out more.
Colum 1 +
Colum 2 +
Publications +
Enjoy presentations from Building Technology & Urban systems research experts on a wide variety of topics in the areas of building energy efficiency, the electricity grid and how it relates to buildings and much more.
- Presentations
News
Tools & Guides +
Explore our tools, guidebooks and software and download for free.

We offer a variety of technologies designed to simulate and model real-world circumstances to assist in energy-saving programs and help building owners build better buildings. These tools can help calculate performance of building systems like windows and shades, help consumers and builders pick the best windows for a variety of applications and much more.

Publications

Publications By Research Area

2005

Levinson, Ronnen M., Paul H. Berdahl, Asmeret A. Berhe, and Hashem Akbari."Effects of soiling and cleaning on the reflectance and solar heat gain of a light-colored roofing membrane."Atmospheric Environment 39.40 (2005) 7807-7824. DOI

Akbari, Hashem, Asmeret A. Berhe, Ronnen M. Levinson, Stanley Graveline, Kevin Foley, Ana H. Delgado, and Ralph M. Paroli."Aging and Weathering of Cool Roofing Membranes." (2005).