BUILDING ENVELOPE FAILURE CASE STUDIES IN HIGH-RISE

CONSTRUCTION

Pierre-Michel Busque, P.Eng.

Building Code

• Objective Based

• Prescriptive

• Mixed

Objective Based Building Codes

• Dangerous when designer’s competence are low

• Evolving performance requirements can make a designer’s skills obsolete

• Unconscious incompetence

Prescriptive Based Building Codes

• Suggest recipes

• But do not guaranty performance

Building Code

• Prescriptive Codes: Limit innovation

• Objective-Based Codes: Gives bad designers free reign.

Society Expects...

• ...that designers perform to the standard of care of a reasonable and prudent professional.

What is the Standard of Care?

• Not what conforms to the building code.

• Not what everybody else is doing.

• Not what has been done.

What meets the theoretical and practical demands of the state of the art.

...what a good father would do for his family.

Within the Standard of Care

•Code Requirements

•Good Practice

•Design Service Life

•Expected Service Life (Clients)

Raised leg No Overlap

Raised leg Overlap

Conclusion

Standard of care of a designer is not clearly defined... Not a recipe.

Performance-based Codes give designers more freedom in the solutions that they implement.

ConclusionChanging performance requirements can make it difficult for designers to meet the standard of care.

Third party warranties on building performance with peer reviews of designs can help ensure that the standard of care is met.