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Addenda to Standard 90.1-1999

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Standard 90.1-1999, Energy Standard for Buildings Except Low-Rise Residential Buildings

NOTE: All documents linked from this page are in pdf_icon.png PDF-format.

(These descriptions may not be complete and are provided for information only.)

pdf_icon.png Addendum a (Clarification to, Substantial Contact.)

pdf_icon.png Addendum d (Clarifies what F-factors should be used for trade-offs in the calculation procedures for slab-on-grade insulation in, Slab-on-Grade Floor Insulation. Appendix A, Section A6.)

pdf_icon.png Addendum e (Clarifies that the calculation procedures in Section A9 can also be used for determining heat capacity of assemblies not covered in Tables A6 and A7.)

pdf_icon.png Addendum f (Revises Appendix B to change the unheated slab-on-grade floor criteria for residential spaces.)

pdf_icon.png Addendum g (Revises Appendix B to change the heated slab-on-grade floor values in Tables 19 through 26.)

pdf_icon.png Addendum j (Changes to 6.2.1, Mechanical Equipment Efficiency, and corresponding Tables 6.2.1C, H, I & J.)

pdf_icon.png Addendum k (Exceptions to, General, have been reworded for clarity and consistency.)

pdf_icon.png Addendum n (Change to the Exceptions to, Shutoff Damper Controls relates to gravity dampers and makes the statement consistent with the requirements of 6.1.3 (n), Simplified Approach Option for HVAC Systems.)

pdf_icon.png Addendum o (Change to, Zone Isolation, clarifies how zones may be grouped and removes the detailed performance requirements.)

pdf_icon.png Addendum q (Deletes, Enclosed Parking Garage Ventilation, in its entirety.)

pdf_icon.png Addendum r (Revises Exception to 6.3.1 (b) with regard to economizers.)

pdf_icon.png Addendum s (Exception to, Economizer Heating System Impact, was added to ensure that code officials would allow economizer operation where reheat was allowed.)

pdf_icon.png Addendum t (Change to, General, and, Air System Balancing, relates to system balancing and removes the exception to

pdf_icon.png Addendum u (Change to Table 6.2.1B, Electrically Operated Unitary and Applied Heat Pumps-Minimum Efficiency Requirements, adds the heat pump minimum efficiency ratings using the ISO procedure that are equivalent to the current requirements.)

pdf_icon.png Addendum v (In, Automatic Lighting Shutoff, the term 'occupant intervention' is vague and needed clarification.)

pdf_icon.png Addendum w (Change to, Space-by-Space Method of Calculating Interior Lighting Power Allowance, clarifies the intended use of this additional interior lighting allowance.)

pdf_icon.png Addendum y (Clarifies the definition of 'General Low Bay' and 'General High Bay' under the heading of Industrial Buildings, Table, Lighting Power Densities Using the Space-by-Space Method.)

pdf_icon.png Addendum z (Change to 9.3.2, Exterior Building Lighting Power, and Table 9.3.2, Lighting Power Limits for Building Exteriors, clarifies the language and intent of exterior building lighting power.)

pdf_icon.png Addendum aa (Change to, Feeders, and, Branch Circuits, specifies that connection load is not always the sizing method used in electrical design.)

pdf_icon.png Addendum ab (Change to 9.3, Prescriptive Path, and Table, Space-by-Space Method of Calculating Interior Lighting Power Allowance, clarifies that the additional power allowances apply to any lighted area that meets the criteria.)

pdf_icon.png Addendum ac (Change to 7.2.1, Sizing of Systems, provides additional wording to the designer for more flexibility in determining the load of the system.)

pdf_icon.png Addendum ad (Numerous changes including Tables 6.2.1A, 6.2.1B,, and 6.1.3;,, &

pdf_icon.png Addendum af (Changes to, strengthens the standard, eliminates the possibility of loopholes.)

pdf_icon.png Addendum ag (Changes to,, A8, Tables A-17, A-17 and A-19. Revise U-factor requirements for glazed wall systems in vertical fenestration to require compliance with NFRA certification programs.)

pdf_icon.png Addendum ah (Change to, allow building area lighting power allowance method to be used for all buildings.)

pdf_icon.png Addendum ai (Change to, adding footnote to Table to indicate specific building types apply.)

pdf_icon.png Addendum ak (Appendix B, Tables B-1 to B-26 (SI only): Revises all U-factors in SI edition to be consistent with the IP edition.)

pdf_icon.png Addendum al (In Section 3 modifies the definition of pump system energy demand. Also, change to, 'mechanical refrigeration' to 'mechanical cooling', and, deleted certain requirements for system balancing.)

pdf_icon.png Addendum am (Changes to subsections of 4.1 and exceptions, rewritten version of Section 4 makes clear the different treatments given to additions and alterations to existing buildings.)

pdf_icon.png Addendum an (Change to 11.4.2, coordinates subsection 11.4.2 with and

pdf_icon.png Addendum ao (Changes to the entire Section 5. No changes to the requirements. The revision simply restructures to make it easier to read and use.)

pdf_icon.png Addendum ap (Wording change to 11.4.3(e) and (f), this clarifies the rules for air and water economizers for budget building design.)