Joint Development of Innovative R-20 Wall Panels by ORNL and SustainBuild
During 2002 a joint collaboration between ORNL and Houston, TX-based SustainBuild was initiated. During 2005 a patent application was filed to the US Patent office for innovative light-gage steel sandwich panels. The main objective of this project was development and experimental validation of a concept novel energy efficient, panelized, building envelope technology.
As shown in Figure 1, this panelized technology is combining the structural elements of sandwich skins and light-gage steel profiles which are characteristic of steel framing, together with a unique application of thermal mass components (active thermal mass inserts containing PCM-phase change material) and a new close-cell polyurethane foam with reduced internal radiant heat transfer (initial tests indicate that the R-value of new foam may range from R-7.0 to R-7.5 – over 30% greater than currently available pentane-blown foams).
Figure 1. Structural components of the new panelized technology.
It is well known, that due to the hot humid climate of Texas & much of the southeastern United States, annual damages due to termites, mold & moisture are significant. The new building envelope system will virtually eliminate these damages. It is further anticipated that this envelope technology will substantially out perform conventional wood frame construction when tested for wind & uplift load tolerances. This R-20 wall technology, coupled with a whole building approach will be capable to reduce peak hour loads & enhance comfort & indoor air quality.
The southeastern states are high-risk insurance areas due to their expansive Gulf of Mexico coastlines& exposure to hurricane & tropical storm related insurance risks. The light-gage steel skin sandwich structure is non-combustible & will provide superior wind performance. Therefore, a significant attribute of this envelope technology will be its disaster resistance resulting in the added benefit reduced insurance risks (&, therefore insurance premiums).
Another significant attribute of this new panelized envelope system is that it will be user-friendly & require generally unskilled labor for the envelope construction. To facilitate the user-friendly attributes, including maximizing construction simplicity and speed, a collection of prefabricated, lightweight component integration panels for corners, window/door connections, etc., was designed. In addition, the panels have the same thickness of the traditional 2X4 frame (compatible with off-the-shelf windows, doors, etc.). their weight will not exceed 80 lbs.(for low-cost no-crane applications). Panels do not require internal conduits, or additional penetrations, for installation of electrical lines.
The panels are 100% recyclable (can be constructed in one building form, then later dismantled & reconstructed into another). This attribute has far reaching possibilities for military use as well as the evolving needs of developing &war-torn countries such as Afghanistan, Iraq, Africa, etc.
more information please contact Dr. Jan Kosny