The Double Skin Façade is a system consisting of two glass skins placed in such a way that air flows in the intermediate cavity. The ventilation of the cavity can be natural, fan supported or mechanical. Apart from the type of the ventilation inside the cavity, the origin and destination of the air can differ depending mostly on climatic conditions, the use, the location, the occupational hours of the building and the HVAC strategy. The glass skins can be single or double glazing units with a distance from 20cm up to 2 meters. Often, for protection and heat extraction reasons during the cooling period, solar shading devices are placed inside the cavity

The cavity between the two skins may be either naturally or mechanically ventilated. In cool climates the solar gain within the cavity may be circulated to the occupied space to offset heating requirements, while in hot climates the cavity may be vented out of the building to mitigate solar gain and decrease the cooling load. In each case the assumption is that a higher insulative value may be achieved by using this glazing configuration over a conventional glazing configuration.

Double skin facade buildings were first built in the US and Europe in the 1970s during the first energy crisis as an attempt to improve building performance.

The recent resurgence of efficient building design has renewed interest in this concept. Since the USGBC rewards points for reduction in energy consumption vs. a base case, this strategy has been used to optimize energy performance of buildings.

The advantages of double skin facades over conventional single skin facades is not clear-cut; similar insulative values may be obtained using conventional high performance, low-e windows. The cavity results in a decrease in usable floor space, and depending on the strategy for ventilating the cavity it may have problems with condensation, becoming soiled or introducing outside noise. The construction of a second skin may also present a significant increase in materials and design costs. [1]

Building energy modeling of double skin facades is inherently more difficult because of varying heat transfer properties within the cavity, making the modeling of energy performance and the prediction of savings debatable


For some applications, double skin facades can be an effective way of layering together dynamic and static elements to increase the performance of window systems. Solar heat gain and daylighting can be managed through an operable blind system in the cavity, which can also be utilized for a range of ventilation strategies including pre-conditioning outside air and creating a solar flue to draw air out of the adjacent spaces. A double skin facade can provide acoustic benefits for buildings with natural ventilation. The cavity can also provide a thermal buffer between interior and exterior to reduce heat loss, although in most commercial buildings cooling is more of an issue than heating. Overheating of the cavity must be balanced with acoustics and other factors for configurations with fixed outer openings, or operable outer openings can be utilized to allow seasonal adjustments.

For tall buildings, where the wind speeds might be too high for dynamic exterior shading devices, a double skin can provide wind protection. Since the 1990s Northern European design teams have sought to improve the performance of highly glazed buildings with double skin facades. The most significant challenges include the high cost, the tendency for overheating in the cavity, and general effectiveness. Building off the lessons learned from earlier installations, a new generation is now being designed and installed with the intent of further improving performance. Experience has led to a better understanding of the trade-offs between thermal performance, daylighting, and acoustics, and is resulting in more selective and strategic use of double skin facades. Simulating and measuring the performance of double skin facades is extremely complicated, but is essential to assure that the strategy is applied appropriately, and that assemblies are properly designed.


http://www.google.com.my/imglanding?q=double%20skin%20facade&imgurl=http://www.pages.drexel.edu/~amn38/images/Construction/Double%2520Skin%2520Facade.jpg&imgrefurl=http://www.pages.drexel.edu/~amn38/Construction%2520Page.htm&h=1224&w=792&sz=169&tbnid=dgq0DcnL-K3yYM:&tbnh=279&tbnw=180&prev=/images%3Fq%3Ddouble%2Bskin%2Bfacade&zoom=1&q=double+skin+facade&usg=__afRdQqQLd9eh7k4mIsFwzlij38s=&sa=X&ei=YkNATb3EHsnLrQfDm53lAg&ved=0CBkQ9QEwAA&start=0#tbnid=BRlAP8wl7lhmWM&start=50