Comprehensive vs. Supplemental Facade Inspection: What’s the Difference?
A comprehensive facade inspection and a supplemental facade inspection are different types of inspections under San Francisco’s Chapter 5F program. A comprehensive inspection includes a 100% visual inspection and a 25% tactile inspection of the exterior facade.
A supplemental inspection focuses on 100% visual inspection of exterior glazing, such as glass and glazing systems.
The main difference is how each inspection is performed and what it evaluates. A comprehensive inspection uses both General and Detailed Inspection methods. A supplemental inspection focuses on the visual evaluation of exterior glazing, with a Detailed Inspection performed when the qualified professional decides it is necessary.
A supplemental inspection does not replace a comprehensive inspection. Each has a different purpose within San Francisco’s Chapter 5F facade inspection framework.
Comprehensive vs. Supplemental Facade Inspection: What Is the Key Difference?
A comprehensive facade inspection uses 100% visual and 25% tactile examination of exterior facades, together with General and Detailed Inspection procedures.
A supplemental facade inspection focuses on 100% visual examination of exterior glazing, with additional detailed Inspection performed when the qualified professional considers it necessary.
Neither should be viewed simply as a more or less extensive version of the other. They use different inspection approaches for different functions within San Francisco’s Chapter 5F framework.
For professional assistance with facade inspection requirements, property owners can visit our Building Facade Inspection Services page in San Francisco.
| Comparison Point | Comprehensive Facade Inspection | Supplemental Facade Inspection |
|---|---|---|
| Primary coverage | Exterior facades | Exterior glazing |
| General Inspection | Required | Required |
| Detailed Inspection | Part of the comprehensive methodology | Performed when considered necessary |
| Visual examination | 100% of exterior facades | 100% of exterior glazing |
| Tactile examination | 25% of exterior facades | No equivalent routine 25% tactile requirement |
| Interior leak survey | Cursory survey included | Not mandatory unless considered necessary |
| Primary methodology | Visual + tactile evaluation | Focused visual glazing evaluation |
What Makes a Facade Inspection Comprehensive?
A comprehensive facade inspection combines a systematic visual inspection of the exterior facade with a closer examination of selected areas.
Under San Francisco’s AB-110 procedures, a comprehensive facade inspection follows the applicable General Inspection and Detailed Inspection procedures referenced in ASTM E2270. These methods help the qualified professional evaluate visible facade conditions and examine selected areas more closely when needed.
How Do General and Detailed Inspections Work Together?
The General Inspection establishes systematic visual coverage of the exterior facade. It allows the qualified professional to observe facade conditions and identify areas that may warrant closer evaluation.
The Detailed Inspection provides a closer level of examination. The methods used depend on the building and the professional's observations during the inspection.
An important distinction involves probes. Probing is not automatically required simply because a Detailed Inspection is being performed. Under AB-110, probes are used when the qualified professional considers them necessary after evaluating exterior indications of facade deterioration.
This combination of systematic observation and closer examination is a defining feature of the comprehensive inspection methodology.
Why Does a Comprehensive Inspection Include 100% Visual Examination?
The comprehensive procedure requires 100% visual inspection of the exterior facades.
Full visual coverage systematically observes the exterior rather than relying on a limited selection of facade areas.
Visual observations can also help guide the Detailed Inspection by identifying locations where closer examination may provide additional information.
However, visual coverage is only one part of the comprehensive methodology. It works together with the required tactile examination.
Why Does a Comprehensive Facade Inspection Include a 25% Tactile Inspection?
A comprehensive facade inspection requires a tactile inspection of at least 25% of the exterior facades. This close-up examination helps the qualified professional evaluate selected facade areas more carefully than visual inspection alone.
During a tactile inspection, selected areas are examined at close range to better understand conditions that may be difficult to assess from a distance.
Simply put:
A visual inspection examines the overall facade, while a tactile inspection provides a closer physical examination of selected areas.
Using both visual and tactile inspection methods provides a more complete evaluation of the exterior facade during a comprehensive facade inspection.
Why Is Water-Leakage Information Considered?
The comprehensive procedure also considers information about the facade’s watertight performance.
AB-110 calls for a cursory interior survey for leaks and consultation with the owner, manager, or other appropriate personnel regarding known water leakage or infiltration. This information may help the qualified professional identify locations where closer exterior evaluation is appropriate.
This does not make the work a separate building-envelope inspection. Instead, leakage history provides supporting information for the facade evaluation.
What Makes a Supplemental Facade Inspection Different?
A supplemental facade inspection is distinguished primarily by what its required visual examination targets: exterior glazing.
Under AB-110, the supplemental procedure follows the applicable General Inspection methodology and includes 100% visual inspection of exterior glazing.
The qualified professional methodically scans applicable glazing and evaluates conditions relevant to the glazing system, including:
out-of-plane displacement;
deterioration;
glazing defects; and
glass breakage.
This glazing-specific methodology is what separates the supplemental inspection from the visual-and-tactile facade methodology used for a comprehensive inspection.
Does a Supplemental Inspection Automatically Require a Detailed Inspection?
No. A detailed inspection is not automatically mandatory as part of every supplemental inspection.
Under AB-110, a detailed inspection and a cursory interior leak survey may be undertaken when the qualified professional considers them necessary.
This is an important methodological distinction. The supplemental procedure begins with its required visual glazing evaluation, while further detailed investigation depends on the conditions observed and professional judgment.
Does a Supplemental Facade Inspection Replace a Comprehensive Inspection?
No. A supplemental facade inspection does not replace a comprehensive facade inspection.
San Francisco’s Chapter 5F framework treats them as distinct inspection requirements. The supplemental provisions operate alongside the comprehensive inspection framework where applicable rather than providing an alternative way to satisfy the comprehensive inspection requirement.
A building may therefore be subject to both inspection types.
This distinction is particularly important when reviewing previous inspection documentation. Completion of a supplemental inspection should not automatically be interpreted as completion of a comprehensive inspection because the required procedures are different.
Detailed questions about which buildings are subject to Chapter 5F and when inspections are required are separate compliance issues and are covered in our Facade Inspection Requirements in San Francisco guide.
How Do Comprehensive and Supplemental Inspections Work Together Under Chapter 5F?
The two inspection types are distinct components of the same regulatory framework.
The comprehensive procedure establishes the visual and tactile methodology for evaluating exterior facades. The supplemental procedure provides an additional glazing-focused evaluation where the supplemental provisions apply.
In simplified form:
Chapter 5F → Comprehensive Facade Inspection → Supplemental Glazing Inspection Where Applicable
The supplemental inspection, therefore, adds a specific inspection function without duplicating the methodology of the comprehensive inspection.
For a broader explanation of the regulatory framework itself, see our Chapter 5F Facade Inspection Explained guide.
Why Does San Francisco Use a Separate Supplemental Glazing Inspection?
The supplemental procedure provides a dedicated inspection methodology for exterior glazing.
Rather than repeating the visual-and-tactile examination used for the exterior facade as a whole, the supplemental General Inspection directs the qualified professional to systematically examine exterior glazing for displacement, deterioration, glazing defects, and glass breakage.
San Francisco’s procedures also recognize appropriate observation technologies. Depending on the inspection circumstances, visual evaluation can involve magnification, remote optical devices, or qualifying remote-sensing methods.
The result is a glazing-specific evaluation that complements rather than duplicates the comprehensive inspection methodology.
Conclusion
A comprehensive facade inspection and a supplemental facade inspection differ primarily in their inspection methodology and the areas examined.
The comprehensive procedure combines full visual facade coverage with 25% tactile examination and the applicable General and Detailed Inspection procedures. The supplemental procedure establishes a focused 100% visual examination of exterior glazing, with closer investigation added when professional judgment indicates that it is necessary.
Understanding this distinction helps prevent the two inspection types from being treated as interchangeable and clarifies how each functions within San Francisco’s Chapter 5F facade inspection framework.
Frequently Asked Questions
Can remote optical devices be used during a supplemental facade inspection?
Yes. San Francisco’s AB-110 procedures allow exterior glazing to be observed with or without magnification or remote optical devices. Appropriate remote-sensing techniques may also be used as inspection means and methods when they meet applicable requirements and are used under the qualified professional’s direction.
Are probes required during every comprehensive facade inspection?
No. Probes are not automatically required during every comprehensive inspection. AB-110 states that they need not be undertaken unless the qualified professional considers them necessary after evaluating exterior indications of facade deterioration.
Can a supplemental facade inspection lead to a closer investigation?
Yes. Although a detailed inspection is not automatically mandatory during a supplemental inspection, the qualified professional may determine that additional investigation is necessary based on observations made during the visual glazing evaluation.
Can glazing records affect supplemental inspection requirements?
Yes. Chapter 5F contains specific provisions on glazing inspection and maintenance records, glass-breakage history, and other prescribed conditions when evaluating certain supplemental requirements. These provisions depend on documented building conditions and should not be assumed without the applicable records and professional review.
Are historic buildings handled differently during facade inspections?
Historic resources can require additional professional considerations. San Francisco’s procedures require applicable expertise in inspecting and maintaining historic resources, and inspection methods should use the least intrusive or invasive means feasible while still effectively evaluating relevant conditions.
