In high rise buildings the glass façades systems are often preferred due to the low maintenance, being
rain screen as well as being lightweight, aesthetic, and durable. In the other side this system cannot be setup
with openings such as windows for ventilation due to wind effect at upper floors. Therefore, this system
increases cooling loads and ventilation systems. A double skin glass façade system has been developed to solve
all these problems. Although the façades are often considered one of the measurable indicators for the cost
efficiency, however cost of the double skin façades need guiding rules.
The aim of this paper is to present a quantitative evaluation methodology that could be used to determine cost
optimal level for standard double skin glass façades alternatives based on enhancing building performance. The
paper concentrates on the initial costs in addition to the maintenance costs, salvage costs and the annual costs
along the life cycle period for the façade.
The paper has generated standard double skin glass façades alternatives that are common used in the building
construction industry based on an extensive literature review, concerning double façade components. In addition,
variables that affect the quantitative evaluation process are identified. Then, these standard double skin glass
façades alternatives are subjected to a proposed quantitative evaluation methodology, which is used to find out
the total present value life cycle cost (TPVLCC). The present value method (PVM) along the life cycle period
for the façade is applied, consequently the research results support the decision-making for investors, architects,
façade engineers and specialists to choose the cost optimal level for double skin glass façades.