Both new buildings as well as remediation of existing building enclosures need to incorporate design that will provide the intended functionality of the wall system. Design of the building enclosure also depends on other factors including structural requirements, mechanical and electrical systems and energy requirements. Remediation of a building enclosure requires thorough planning to ensure that the problems that the building was facing are properly corrected. It is important to spend as much as required for the design process so as to reduce the impact of changes during construction. However, there are some elements that cannot be ascertained or verified prior to construction.