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Standards, Research & Technology

Addenda to Standard 90.1-2007 IP SI Versions

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

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

Addendum ac (ac: This addendum modifies requirements for controls in the following applications: personal
and manual dimming, multi-scene, manual and automatic bi-level switching, daylighting

Addenda ag, ai, aj, ak, ay, bc, bd (ag: This adds a requirement for joint insulation overlap. ai: This clarifies how distribution pump energy is to be addressed when using purchased heat or purchased chilled water. aj: This update the test and table of Chapter 10 to comply with the new federal law. Since the new law and the new version of ASHRAE 90.1 will both occur in 2010, this change will ensure that there is no confusion about the new energy efficiency standards for motors that are manufactured in 2010 and beyond. ak: This modifies requirements for Heat Pump and Water-Cooled Unitary Air-Conditioners, Differential Pressure Reset, fan power limitations, chilled water cooling, and deletion of 10 HP from Section 6.5.4. ay: This change more correctly requires users to identify spaces by function and is consistent with a previous interpretation. It is expected that the net energy result will be positive. bc: This clarifies that the requirements in Section are also specified for unconditioned spaces. bd: This addendum removes emergency circuits not used for normal building operation from the requirements which will lead to increased compliance.)

Addendum al (al: This adds skylight requirements in certain space types to promote daylighting energy

Addenda am, aq, ax (am: The intent of this addendum is to revise air leakage criteria so they more closely reflect
current practice.
aq: This addendum modifies the Purpose and expands the scope so the standard may regulate
process loads. ax: This modifies requirements for kitchen exhaust.)

Addenda ar, av, bp (ar: This addendum adds exterior lighting power requirements. av: This modifies the requirements of section 9.1.2 Lighting Alterations and replaces the previous public review draft of addendum "av" in its entirety. bp: This allows the use of control that provides automatic 50% auto on with the capability to manually activate the remaining 50% and has full auto-off.)

Addenda bf, bn, bs (bf: This provides performance requirements for air leakage of the opaque envelope. bn: This limits poorly oriented fenestration. Compliance can be shown by having more south facing fenestration than west facing fenestration. For those buildings affected by this requirement, this reduces envelope loads, energy usage and thereby costs. bn: This limits poorly oriented fenestration. Compliance can be shown by having more south facing fenestration than west facing fenestration. For those buildings affected by this requirement, this reduces envelope loads, energy usage and thereby costs. bs: This new requirement will provide the means for non-critical receptacle loads to be automatically controlled (turned off) based on occupancy or scheduling without additional individual desk top or similar controllers)

Addenda bi, bt (bi: This provides updated requirements for pipe insulation. bt: This addendum modifies centrifugal chiller adjustment factor for nonstandard conditions.)

Addendum bu (bu: This addendum adds efficiency requirements to HVAC systems dedicated to computer rooms and data centers)

Addenda bx, by, ca, cb, cc (bx: This addendum modifies VAV reheat requirements. by: This proposes new Lighting Power Densities for both the whole building and space-by-space compliance methods. In addition, the Lighting Power Density may be re-calculated based on room geometry. ca: This change closes a loophole in the fan power allowances for Variable Air Volume (VAV) systems. Standard VAV systems are multi-zone systems with terminal units containing control dampers to vary airflow to individual zone. cb: This addendum includes a number of changes to require simple systems to meet prescriptive outdoor air damper requirements, allow backdraft dampers only for exhaust and relief dampers in buildings less than three stories in height, require backdraft dampers on outdoor air intakes to be protected from wind limiting wind blown infiltration through the damper.. cc: This addendum fixes a mistake in the way 200 mm pipe was analyzed. RS Means data for threaded pipe was used for 8" when welded pipe data should have been used. It also includes a minor editorial change since it is not possible to operate more than 8760 hrs/yr.)

Addenda cd, ck, cn, cq, ct, cv (cd: These additions 1) strengthen the language to actually require exterior control rather than just require the control capability; 2) add bi-level control for general all-night applications such as parking lots to reduce lighting when not needed; 3) add control for façade and landscaping lighting not needed after midnight. ck: This addendum expands zone level demand controlled ventilation to include various forms of system level strategies. cn: This change adds two versions of a combined advanced control to the control incentives table. These control systemcombinations involve personal workstation control and workstation-specific occupancy sensors for open office applications. The control incentive will apply only to the particular controls when they are applied in open office areas.. cq: This addendum modifies the duct sealing requirements in ANSI/ASHRAE/IESNA Standard 90.1-2007. ct: This addendum sets controls for the the "night lights" that are part of the emergency system when there are no occupants in the space. This has definite energy savings and is not prohibited by the electrical codes. cv: This addendum adds energy efficiency requirements for service water pressure booster systems.)

Addenda ce, cp (ce: This additional control requires that all spaces (unless exempted) have multilevel control capability (also commonly known as bi-level switching). cp: This proposal establishes, for the first time in ASHRAE 90.1, efficiency requirements for VRF air conditioners and heat pumps, including heat pumps that use a water source for heat rejection.)

Addendum cf (cf: Stairwell lighting represents the "Emergence Egress Light Level" with stairwell occupancy. However the occupancy percentage of a stairwell is only 10%, thus offering savings. Various case studies and demonstrations have shown significant energy savings for this strategy.)

Addenda ch, cl, db (ch: This addendum makes Appendix G and Section 11 consistent with requirements approved in Addenda h (dual minimum controls) and as (lab exhaust). cl: The proposed text would clarify how to interpret the use of dynamic glazing products that are designed to be able to vary a performance property such as SHGC, rather than having just a single value.. db: This addendum modifies the fan power requirements in the energy cost budget section.)

Addenda cr, cs, cw, cz, da, dc (cr: The definition for an unmet load hour is currently lacking a throttling range or limit to the setpoint. It was decided that the baseline and proposed shall have the same thermostat throttling range. This required additional language in the unmet load hour definition as to how throttling range effects determination of an unmet hour along with additional language in Table 11.3.1 and Table G3.1, Design Model sections.. cs: This change originated with a continuous maintenance proposal to address information received on addendum bs on receptacles after the public review period closed and which the committee found to have merit. cw: These changes address corrections and clarifications necessary to Section 11, Table 11.3.1 and Section 11 Service Hot Water Systems. cz: This change incorporates bi-level control for parking garages to reduce the wasted energy associated with unoccupied periods for many garages AND allows an exception for lighting in the transition (entrance/exit) areas to accommodate IES recommendations.. da: The intent of this addendum is to establish that an Appendix G baseline shall be based on the minimum ventilation requirements required by local codes or a rating authority and not the proposed design ventilation rates.. dc: The conditions and common practice that existed to create the need for this requirement on tandem wiring are no longer practiced primarily with the new Federal efficacy requirements and products available on the market.)

Addenda cy, co, dd, de, df (cy: This addendum makes several revisions to the economizer requirements in Section 6.5.1 and in Section 6.3.2. With increased envelope insulation levels and higher internal plug loads we are seeing commercial buildings operating in cooling at lower ambient temperatures. This allows for greater air and water economizers to be used instead of mechanical cooling.. co: This proposal makes three major amendments to Table 6.8.1A. First, it updates EER and IEER values for all condensing units and water and evaporatively cooled air conditioners with cooling capacities greater than 19 kW. Second, the proposal establishes a separate product class for evaporatively cooled air conditioners with different energy efficiency standards. Third, the proposal replaces the IPLV descriptor for condensing units with the new IEER metric and amends the EERs with more stringent values. dd: This addendum modifies the VAV fan power limitation requirements. de: This addendum lowers the Lighting Power Densities in 90.1 to reflect advances in lighting technology.. df: This addendum sets requirements elevator ventilation and lighting, which have been unregulated, regardless of occupancy.)

Addenda d, o, x, aa, ab, ae, at, au, ba (d: This addendum modifies the daylighting requirements to allow the use of photocontrols combined with skylighting to reduce the electricity used for lighting. o: This provides the necessary pressure credits for laboratory exhaust systems that allow prescriptive compliance of systems serving fume hoods. x: This revision updates the requirements for automatic lighting shutoffs, adds specific occupancysensor applications, and provides additional clarification. aa: This change mandates that lighting controls have a "manual on" capability. ab: This change modifies skylighting and daylighting requirements from addendum "d" to 90.1-2007.. ae: This change adds requirements for radiant heating panels.. at: This change modifies the exhaust air damper requirements in 90.1. au: This change modifies the economizer requirements in Standard 90.1. ba: This a system performance option that allows compensating for the insulating value of the piping while maintaining the same net thermal requirements.)

Addenda dg, di, dj, dk, dl (dg: This addendum adds a definition for the term field fabricated used in Section, which is similar to the definition in CA Title 24. di: This addendum allows for a reduction in ventilation in uncontaminated garages. dj: This addendum provides limits on the pressure drop of energy recovery devices. dk: This addendum makes 90.1-2010 consistent with changes made in addenda al, bc, and bn. dl: This addendum gives instruction to the users of Appendix C on how to model the base envelope design and the proposed envelope design in complying with the cool roof provisions in Section 5..)

Addenda dn, do, dp, dq, dr (dn: This addendum modifies the efficiencies for variable refrigerant flow equipment. do: This addendum attempts to clearly establish the goals and requirements of the lighting system including controls and to ensure that the owner is provided all information necessary to best use and maintain the lighting systems. dp: This addendum updates the references in Standard 90.1. While these changes reflect the current edition of the cited standard it should be noted that substantive changes in the referenced documents did not affect the requirements in 90.1 or change the stringency of the requirements of 90.1.. dq: This addendum modifies the calculations found in Appendix C in order to reflect modifications to the modeling assumptions in the equations.. dr: The original purpose for this provision was to limit the use of inefficient lighting sources for high wattage applications when there was not a comprehensive table of exterior LPD limits. With the table of requirements now in the 2007 and beyond versions of the standard, the need for this limit is superseded..)

Addenda e, as, az, bg, bh, bj, bk, bl, bm, bo, bq, br, bv, bw (e: This addendum modifies the requirements for Energy Recovery by expanding them to cover the use of energy recovery by weather zone as: This addendum adds lab exhaust requirements. az: Lighting controls must be functionally tested to ensure their proper use and appropriate energy savings. This addendum provides requirements for those tests.. bg: This provides requirements for water-to-water heat pumps. bh: This provides requirements for multiple zone HVAC systems (that include simultaneous heating and cooling) to include controls that automatically raise the supply-air temperature when the spaces served are not at peak load conditions. bj: This adds an exception within Appendix G that allows users to claim energy cost savings credit for the increased ventilation effectiveness of certain HVAC system designs.. bk: This language distinguishes Subtype I and Subtype II motors. Addendum "aj" to ASHRAE Standard 90.1-2007 first incorporated these changes into Standard 90.1. This proposed language has different minimum efficiency requirements as called out in EISA 2007, Section 313 and clarified in the Federal Register.. bl: This adds requirements for chillers with secondary coolants (glycol or brine). In additions, there are changes to footnote a to Table 6.8.1C in recognition of lower practical scope limits for positive displacement (both air- and water-cooled) and corrects for the lower limit introduced in Addendum M for centrifugal chillers.. bm: The intent of this addendum is to coordinate terminology for visible transmittance with NFRC 200. bo: This is part of an ongoing effort to keep the requirements of Section 11 and Appendix G consistent with other addenda to the Standard. This addendum makes changes to Section 11 and G related to Addenda e, s, and u.. bq: This changes the requirements for retail space lighting which will make use of more recent lamp technology that is readily available. br: This adds an exterior zone 0 to cover very low light requirement areas. bv: The addendum makes Appendix G of Standard 90.1 consistent with addenda aj, bk, and ax.. bw: The addendum modifies efficiency requirements for packaged terminal air conditioner( PTAC)..)

Addendum f (f: This addendum sets requirements for high-albedo roofs.)

Addenda v, af, an, ao, ap (v: This modifies the requirements for axial fan open circuit cooling towers. af: This change modifies the pipe sizing requirements. an: This expand the table of default U-Factors for single digit rafter roofs.. ao: This corrects errors in Table 6.8.1E, re-orders footnotes, and changes one efficiency. ap: This modifies the requirements for Demand Control Ventilation (DCV)..)