Many 1960's high rise facades remain in their originally constructed state some 40 years later despite standards having increased 5 fold for U values.
The concept of overcladding is now well established as a means of regenerating older buildings. Rapidly increasing environmental pressures are changing the outcome of the 'option appraisal process' to the extent that the case for 'refurbishment' is now irresistible over the alternative options of 'leave and maintain' or 'demolish and rebuild'.
Provided an existing building is structurally sound, new overcladding can serve to restrain and protect the existing facade such that the regenerated buildings life expectancy is comparable to that of a new building. Warranties are available to cover both the existing structure/facade and the new overcladding as they are mutually dependent upon one another for performance and longevity.
A wide variety of cladding solutions exist that offer a equally wide variety of life expectancies, performance and aesthetic properties. To refurbish, meeting only minimum standards, extending the buildings life short term for say 20 years is to pass our inherited problem to the next generation. Quality, long term, 60 year life systems exist that can readily surpass current standards by 50% for additional capital expenditure of circa 15% over the cheapest solution. These should be adopted wherever possible.
Feasibility assessment must be accurate and comprehensive to allow the 'informed decision making process' to work effectively. Past project examples of most cladding and window options are available up to 20 years old that can be examined and reported upon such that the industry learns and progresses, improving efficiency and the delivery process per Egan report 're-thinking construction'.
Project delivery and subsequent performance is pre-determined by the procurement process. Client risk can be reduced with clear responsibilities from the outset, normally achieved via a Design Build contract. We recommend that track record and references be rigorously investigated as they clearly demonstrate the product and service that will ultimately be delivered.