DC Code Updates for Engineers

Read the engineer's guide to DC energy performance building codes.

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This resource is available courtesy of DCSEU.

The table below highlights the key code changes/updates and provides insight on what might be impacted from a design and equipment selection process, as well as what other parties the MEP engineer might be responsible for coordinating with, in terms of verifying compliance with sections of the energy code. All code sections below reference the 2017 DC Energy Conservation Code, unless otherwise noted.

 

Code subsection Summary Key items for MEP engineers to track
2017 DC Building Code 101.10.6 Alternative Compliance Paths for Commercial Building Projects Text includes alternative compliance paths and requirements for Appendix Z; ILFI for full LBC, Energy Petal and Zero Energy certification; PHIUS and Onsite Solar; PHI and Onsite Solar; and LEED Zero Carbon and Zero Energy Certification. Works with owner and architect on setting project energy codes. Provides feedback on different code compliance paths.
Definitions 3.2 Alters baseline building design and baseline building performance definitions. Has implications for projects that follow the performance compliance path. May require some coordination with energy modeler.
Strikes primary side-lighted area and secondary side-lighted area and insets a single definition for side-lighted area. Impacts how the daylight zone is calculated and determines the daylight-responsive lighting control requirements within those zones.
Alters performance rating method and rating authority definition Has implications for projects that follow the performance compliance path.
Inserts definition for thermal barrier and thermal bridge. Impacts how thermal insulation requirements are calculated. May impact key decisions regarding HVAC system sizing and selection and the location of mechanical and plumbing penetrations.
5.1.3 Envelope Alterations Strikes existing language and replaces with revised scope of envelope alterations. Impacts scope of work for building alterations regarding roof insulation and window replacements. May have implications for mechanical system design and sizing.
5.2 Compliance Paths Adds text making Section 5.4 mandatory for the Performance Method (Appendix G). Makes all the new requirements of Section 5.4 mandatory for projects following the performance compliance path. This means that those requirements cannot be traded off for other efficiency gains.
5.4.1.1 Accounting for Thermal Conduction Components Strikes continuous thermal barrier language and replaces with requirements for accounting for thermal bridging by incorporating it into the area-weighted U-value methodology. Includes default cladding attachment coefficients. Impacts how thermal insulation requirements are calculated. May impact key decisions regarding HVAC system sizing and selection and require coordination with architect on the location of mechanical and plumbing penetrations.
5.4.4 On-Site Renewable Energy Systems New solar-ready requirements for at least 25% of horizontal projection of roof area. Impacts the design and sizing of on-site renewable energy systems. Requires coordination with the renewable energy requirements of Section 13.
5.5.1 Prescriptive Envelope Option Updates for assemblies and fenestration Climate Zone 4. Impacts mechanical system design and sizing criteria.
Table 5.5 Building Envelope Requirements Updates U-factors and R-values for assemblies and fenestration in Table 5.5 for Climate Zone 4.
5.5.4.2 Fenestration Area WWR not to exceed 40%.
Table 5.5.4.4.1 SHGC Multipliers for Permanent Projections Updates for SHGC multipliers for PF based on orientation.
6.3.2 Criteria Adds language for projects that comply with the Alternate Renewables Approach that triggers the higher performance HVAC tables (189.1) in Section 13.1.1.2 and ENERGY STAR heating and cooling requirements in Section 10.11.2. For projects larger than 10K sq. ft. that have selected the Alternate Renewables Approach, these requirements impact the design of on-site renewable energy systems and the efficiency rating criteria for mechanical equipment. Requires some coordination with architect and Cx agent.
6.4.1.1.1 Higher-Efficiency Requirements Adds language for projects complying with the Alternate Renewables Approach in Section 13.1.2.
6.4.1.1.2 Heat Pump Requirement Adds requirement for the use of a heat pump as primary heating source for spaces that are both heated and cooled using unitary systems. Impacts mechanical system design, selection and sizing for projects using unitary systems to meet their heating and cooling loads. Requires some coordination with architect and Cx agent.
6.4.3.8 Ventilation Controls for High-Occupancy Areas Replaces language to expand DCV requirements for densely occupied spaces served by air-side economizer, automatic modulating control of OA dampers or a design outdoor airflow greater than 1000 cfm. Impacts ventilation system design and documentation requirements for densely occupied spaces where the outdoor airflow is greater than 750 cfm. Requires some coordination with architect and Cx agent.
6.4.3.8.1 Design of DCV System Add language requiring DCV to be in compliance with 62.1-2013 and includes CO2 sensor requirements. Impacts DCV control strategy, documentation, and the placement of CO2 sensors. Design documents must include occupant CO2 generation assumptions. Requires some coordination with architect and Cx agent.
6.4.4.1.2 Duct and Plenum Insulation Replaces language to include requirements for projects complying with Chapter 13. Impacts distribution systems for projects that choose the Alternate Renewables Approach as described in chapter 13.
6.4.4.1.3 Piping Insulation Replaces language to include all branch piping and piping components. Impacts plumbing documentation and specifications and may impact sizing of SHW equipment.
Table 6.5.1-1 Minimum fan cooling unit size for which an economizer is required for comfort cooling Replaces existing tables with new table that lowers cooling capacity requirement for which an economizer is required. Impacts equipment selection by requiring an economizer for cooling equipment with a capacity of 33,000 Btu/h. Requires some coordination with Cx agent.
6.5.1 Economizers Replaces language to include requirements for computer rooms, two stage capacity control (for systems <54,000 Btu/h) and for resetting the supply air temperature up at least 5 degrees during economizer operation. Also includes additional exceptions. Impacts economizer selection criteria for computer rooms and control strategy that includes two-stage capacity and the ability to reset the supply air up at least 5 degrees. Requires coordination with Cx agent.
6.5.2.1 Zone Controls Replaces language to remove a number of exceptions that apply to DDC. Impacts HVAC control selection criteria and functionality criteria. Requires coordination with Cx agent.
6.5.3 Air System Design and Control Replaces language to include specific requirements for hotels and motels with more than 50 guest rooms. Impacts fan and fan control selection criteria in hotel and motel guest rooms. Requires some coordination with Cx agent.
Table 6.5.3.1-1 Fan Power Limitation Replaces table to reduce fan power limits. Impacts mechanical system design and fan selection criteria.
6.5.3.1.3 Fan Efficiency Replaces language to lower the design point of operation of the maximum total efficiency of the fan. Impacts fan selection criteria and specifications.
6.5.6.1 Exhaust Air Energy Recovery Replaces language to increase energy recovery effectiveness from 50% to 60%. Impacts exhaust air approach and selection of energy recovery device. Also requires some coordination with Cx agent.
6.5.6.3 Supermarket Heat Recovery Adds new language for supermarkets 25,000 sq. ft. or larger to recover waste heat from the condenser heat rejection on refrigeration and or HVAC equipment. Impacts the design of supermarket HVAC and refrigeration systems and the selection criteria for heat recovery strategies. Also requires some coordination with Cx agent.
6.5.7.1.3 Kitchen Exhaust Systems Replaces language to lower cfm threshold for hoods from 5,000 to 2,000 for establishing max net exhaust flow rates. Impacts the design of kitchen exhaust systems and hood selection criteria. Requires some coordination with Cx agent.
6.5.7.1.4 Kitchen Exhaust Systems Replaces language to lower the total kitchen exhaust air-flow rate from 5,000 cfm to 2,000 cfm for when efficiency requirement apply. Adds control requirements. Impacts the design of kitchen exhaust systems control strategy and selection criteria. Requires some coordination with Cx agent.
6.5.12 Automatic Control of HVAC in Hotel/Motel Guest Rooms Adds new language to require automatic HVAC controls in hotels and motels with more than 50 guest rooms. Include setback control and ventilation control requirements. Impacts the selection of HVAC controls for hotel and motel guest rooms. Requires some coordination with Cx agent.
7.4.2 Equipment Efficiency Replaces language to include the Alternate Renewables Approach in Section 13.1.1.2 and the ENERGY STAR requirements for SHW in Section 10.11.2 Impacts the selection of SHW equipment and appliances if the Alternate Renewables Approach is selected.
8.1.5 Establishing an open and interoperable automated demand response infrastructure Adds new language for Auto-DR for HVAC systems to reduce peak heating and cooling demand (by 10%) and logic to prevent a rebound peak. Buildings where there is not a DR program, where the electric demand is not greater than .75 of the standard reference design and where 20% of buildings demand is met by on-site renewable generation are exempt. For projects required to meet AutoDR requirements, impacts the selection of HVAC controls and requires coordination with Cx agent. For projects required to meet on-site renewable generation requirements, requires coordination with architect, energy modeler, and Cx agent.
8.4.2 Automatic Receptacle Control Replaces language to include one controlled receptacle in each private office and at each workstation. Impacts electrical design and controls specification. Requires some coordination with Cx agent.
8.4.3 Energy Metering and Reporting Replaces language to include distribution design/load isolation for HVAC, lighting, PPLs; the capability to meter peak demand for different fuels; and submetering for project 25,000 sq. ft. and larger. Projects less than 25,000 sq. ft. need to be submeter-ready. Impacts electrical design and metering approach and selection. Requires some coordination with Cx agent.
8.5.1 Automatic Control of Equipment in Hotel/Motel Guest Rooms Adds language for hotel/motels with more than 50 guest rooms requiring automatic switched outlet control and television control. Impacts electrical design and control requirements in hotel and motel guest rooms. Requires some coordination with Cx agent.
9.1.1 Lighting Scope Replaces language to include additional requirements in exception #2: Dwelling units are only exempt when 85% of the lamps in permanently installed luminaires are high efficacy. Impacts lighting design and luminaire selection. Requires coordination with architect.
9.1.2 Lighting Alterations Replaces language in the exception where alterations that involve less than 50% (from 10%) of the connected lighting load in a space need to comply with requirements. Impacts scope of work for building alterations regarding lighting retrofits.
9.1.4 Interior and Exterior Luminaire Wattage Replaces language to include an exception to criteria a, when lighting is connected to a current limiter and containing high efficacy lamping it should use the wattage of the current limiter and not the max wattage of the luminaire. Impacts the selection criteria for high efficacy lamping that is connected to a current limiter.
9.4.1.1 Interior Lighting Controls Replaces language to include an exception to requirement d. Bi-level Lighting Control where existing and or renovation spaces are not required to provide bi-level control in areas where no work is to be performed. Impacts scope of work for building alterations regarding lighting retrofits.
Removes language that applies to the secondary side-lighted areas and adds exception 4 to the photocontrol requirement where the interior LPD is 20% below the listed LPD. Impacts lighting and daylighting design and the selection of photocontrols if not 20% below the LPD threshold. Requires some coordination with architect and Cx agent
Threshold for daylighting controls for top lighting is lowered from 150W to 105W in areas under skylights or roof monitors. Impacts lighting and daylighting design and the selection of daylight responsive controls. Requires some coordination with architect and Cx agent.
Item h extends the automatic shutoff requirement for restrooms to 30 minutes and 20 minutes for all other spaces. Impacts the selection of lighting controls and their functionality requirements as characterized in the BOD. Requires coordination with MEP and Cx agent.
9.4.1.4 Exterior Lighting Control Adds language that applies to uncovered parking areas (9.4.1.4.1 Parking Lighting) that includes control requirements. Updates values in Table 9.4.2-2. Impacts exterior lighting design and control specifications. Requires coordination with Cx agent.
Table 9.5.1 Replaces table to updates LPDs. Impacts interior lighting design and luminaire selection. Requires some coordination with architect.
9.5.2 Prescriptive Control Requirements Adds section that includes Automatic Control of Lights requirements for Group R-1 Occupancies (9.5.2.1); Occupancy Sensor Control with Multilevel Switching or Dimming in commercial and industrial storage stack areas (9.5.2.2); Automatic Controls for Egress and Security Lighting (9.5.2.3); and Controls for Exterior Sign Lighting (9.5.2.4). Impacts interior lighting design, lighting control specifications, and how lighting control functionality is characterized in BOD. Requires coordination with architect and Cx agent.
Table 9.6.1 Replaces table to update LPD values for some common space types. Impacts interior lighting design and luminaire selection. Requires coordination with architect.
9.6.2 Additional Interior Lighting Power Replaces language to include additional lighting power allowances as a percentage of the values in Table 9.5.1. Impacts lighting design for retail areas. Requires some coordination with architect.
9.6.3 Prescriptive Controls Replaces language in order to specify that projects must comply with the prescriptive control requirements of 9.5.2, 9.5.3, 9.5.4, and 9.5.5. Impacts lighting design as additional power allowance is no longer accepted for spaces with non-mandatory lighting controls. Requires coordination with architect.
10.5 Prescriptive Compliance Path Adds new prescriptive compliance requirements including ENERGY STAR for new equipment (10.5.1 and 10.5.2), and specifies the requirements for projects complying with the Alternate Renewables Approach. Impacts the selection of ENERGY STAR-rated equipment including appliances, heating and cooling equipment, SHW equipment, LED lighting, and commercial food service equipment. Requires coordination with architect and owner.
10.5.3 Programmable Thermostats Adds new prescriptive compliance requirements for programmable thermostats (10.5.3). Impacts the specification requirements of residential programmable thermostats. Requires coordination with architect.
10.5.4 Refrigerated Display Cases Adds new prescriptive compliance requirements for refrigerated display cases (10.5.4). Impacts the design and specification of refrigerated display cases to ensure that they are sufficiently covered. Requires coordination with architect.
11.2 Compliance All provisions of Section 11 are mandatory. Impacts code compliance requirements.
11.3.1 Construction Includes acceptance testing and commissioning requirements including requirements for Envelope Commissioning/Testing (11.3.1.3). Impacts acceptance testing and commissioning scope, required acceptance testing activities and submittal timeframes. Requires coordination with architect, Cx agent and owner.
13.1 Prescriptive Renewable Path Adds new code section that requires either the Standard Renewable Approach (13.1.1.1) or the Alternate Renewables Approach (13.1.1.2) for projects 10,000 sq. ft. or larger. Impacts the design of on-site renewable energy systems as required by the standard or alternative renewable energy approaches. Requires coordination with owner, architect, Cx agent and structural engineer. If it is determined that on-site renewable energy is not viable, owner must commit to purchasing renewable electricity products.
13.2 Adoption of Normative Appendix B Adds the equipment efficiency tables for the Alternate Reduced Renewables and Increased Equipment Efficiency Approach as specified in ASHRAE 189.1-2014. Impacts the selection of HVAC equipment and appliances for projects complying with the Alternate Renewables Approach. Requires coordination with architect and Cx agent.
Appendix G Replaces entire section to reflect the code updates/additions. Impacts the use of the energy modeling code compliance path. Requires coordination with architect and energy modeler.
Appendix Z Adds new alternative compliance path for project interested in pursuing higher levels of performance. Impacts project scope, energy goals, and code compliance submittal requirements. Requires coordination with owner and architect.
Z2 Minimum Performance Requirements Includes energy use target (zEPI of 30), TEDI requirements for annual heating and cooling demand and airtightness testing requirements. Impacts the design of the thermal envelope and HVAC system selection and design. Requires coordination with architect, energy modeler and owner.
Z3 Renewable Energy Specifies amount and acceptable sources of renewable energy and include a ban on on-site combustion. Impacts the design and sizing of on-site renewable energy systems and the selection of HVAC systems. Requires coordination with architect, energy modeler and building owner.
Z4 Energy Metering, Monitoring and Reporting Requires metering of all forms of energy delivered to the site, flow rates for all centrally ventilated building systems, and consideration of on-site energy storage options. Impacts the electrical design and specification of meters. Requires coordination with architect and Cx agent.
Z5 Energy Reporting Requirements for post-occupancy measurement and reporting. Impacts energy metering and reporting functionality. Requires coordination with owner and MEP.
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