Presentation on theme: "ENERGY STAR Multifamily High Rise Program"— Presentation transcript:
1 ENERGY STAR Multifamily High Rise Program Introduction to the Prescriptive PathJuly 2011The EPA’s Multifamily High Rise Program offers eligible buildings two Paths to earning the ENERGY STAR.This webinar will explain in detail what is required in the Prescriptive Path. The webinar for the Performance Path should be viewed prior to this one, as it reviews the Prerequisites that are common in both paths. During this webinar, having a printed copy of the Prescriptive Path is recommended.
2 Prescriptive Path Components PrerequisitesPerformance TargetSimulation GuidelinesPerformance Path CalculatorModeling ChecklistPrescriptive RequirementsTesting and Verification (T&V)BenchmarkingBy the end of this webinar, you will be familiar with all the components of the Prescriptive Path.If you’ve already completed the webinar on the Performance Path, you’ll notice that the components related to energy modeling are not components in this Path.The Prescriptive Path is the non-modeling approach to earning the ENERGY STAR.The Prerequisites are the same mandatory requirements as in the Performance Path.The Prescriptive Path simply adds additional requirements in order for the building to achieve similar energy costs savings as a building selecting the Performance Path. These requirements were based on other known Standards and the buildings that participated in the Multifamily High Rise Pilot.Testing and Verification and Benchmarking are required in both Paths.
3 Prerequisites & Prescriptive Requirements AppliancesHeating and Cooling Equipment & DistributionEnvelopeGarages and SidewalksVentilation and InfiltrationDomestic Water HeatingLightingPump Motor EfficiencyIn contrast to the Performance Path, there are no trade-offs when selecting the Prescriptive Path.Unless local code prevents you from doing so, you must meet or exceed all Prerequisites and additional Prescriptive requirements to earn the ENERGY STAR. Although less flexible, the benefit is generally the cost savings from avoided energy modeling and ease of duplicating specs for multiple buildings.The Prerequisites and Prescriptive requirements have been grouped into the following categories: Appliances, Heating and Cooling Equipment & Distribution, Envelope, Garages and Sidewalks, Ventilation and Infiltration, Domestic Water Heating, Lighting, and Pump Motor Efficiency.Some of the Prescriptive requirements simply repeat ASHRAE requirements or Prerequisites; some exceed them.The following slides will show you the Prerequisites and where the Prescriptive requirements exceed that criteria, they will be shown in red.33
4 AppliancesWhen provided in common areas and/or apartments, refrigerators, dishwashers, clothes washers, ceiling fans, ceiling exhaust fans, in-line exhaust fans and vending machines must be ENERGY STAR qualified.No additional Prescriptive requirement.Appliances – Many ENERGY STAR qualified appliances and residential products are available today and meet energy efficient criteria set by the EPA. Because the following are readily available as ENERGY STAR qualified, it is a requirement of the program that refrigerators, dishwashers, clothes washers, ceiling fans, ceiling exhaust fans, in-line exhaust fans and vending machines are ENERGY STAR qualified when provided in the building.There is no additional Prescriptive requirement.
5 Heating and Cooling Equipment – ASHRAE Mandatory Provisions The heating and cooling systems must comply with ASHRAE , Section 6.4.In addition, the systems must also comply with Prescriptive Path Section 6.5.Heating and Cooling Equipment.In the Performance Path webinar, you were introduced to the mandatory provisions of ASHRAE Chapter 6 covers heating and cooling equipment. Section 4 of most ASHRAE chapters outlines the mandatory provisions determined by ASHRAE. Meeting those provisions are one of the requirements of this Program, regardless of Path selected. ASHRAE provides a 2-page checklist that can help you verify whether the building has met those mandatory provisions listed in Section 6.4.For projects following the Prescriptive Path, compliance with Section 6.5, is also required. An additional 2-page checklist is available to verify compliance with this section.Neither of these ASHRAE checklists are required to be submitted to the EPA, but are available to assist the design team in ensuring that these requirements are being met.5
6 Heating and Cooling Equipment – Sizing and Load Calculations Load sizing calculations must reflect the design. The installed capacity cannot exceed design by more than 20%, except when smaller sizes are not available.Loads must be calculated and equipment selected per latest editions of ACCA Manual J & S, ASHRAE 2009 Handbook of Fundamentals, or equivalent procedure.No additional Prescriptive requirement.The heating and cooling sizing and load calculation requirement is the same in both Paths. Load sizing calculations must reflect the design. The installed capacity cannot exceed design by more than 20%, except when smaller sizes are not available. Loads must be calculated and equipment selected per latest editions of ACCA Manual J & S, ASHRAE 2009 Handbook of Fundamentals, or equivalent procedure, and must use the appropriate temperatures.As reviewed in the Performance Path webinar, indoor temperatures must be 70 degrees Fahrenheit for heating and 75 degrees Fahrenheit for cooling and outdoor temperatures must be the 1.0% and 99.0% design temperatures.This prerequisite is the same in both Paths.
7 Heating and Cooling Equipment – Minimum Efficiencies See Table 1 for list of equipment and minimum efficiencies per ASHRAE climate zones.See ASHRAE for equipment not listed in Table 1.Since modeling is not allowed in this Path, the Prescriptive Path establishes minimum efficiencies for many possible types of heating and cooling equipment that must be met.Table 1 of the Prescriptive Path lists the most common systems found in multifamily high rise buildings and the minimum efficiency required of those systems to participate in this path.If your system is not listed, refer to the equipment tables in ASHRAE , Standard for the Design of High-Performance, Green Buildings.
8 Heating Equipment – Prescriptive Requirements No electric resistance space heating is permitted in any space.Atmospherically vented gas furnaces and boilers cannot be specified.The next few slides will review examples of the Prescriptive requirements related to heating equipment:When following the Prescriptive Path, no electric resistance space heating is permitted in any space, in any climate zone. If the design cannot avoid electric resistance heating, then the Performance Path would need to be followed instead.Atmospherically vented furnaces and boilers cannot be specified in any climate zone. This is the same Prerequisite as in the Performance Path.
9 Heating Equipment – Minimum Efficiencies for Boilers In Climate Zones 1-5: Boilers < 300,000 Btuh must be ≥ 85% AFUE.In Climate Zones 6-8: Boilers < 300,000 Btuh must be ≥ 90% AFUE.Boilers ≥ 300,000 Btuh must be ≥ 87% Et, or ≥ 89% Et if used with water-source heat pumps.Although not all equipment in Table 1 will be reviewed in this webinar, the most common systems will be.Hot water boilers (gas or oil-fired) less than 300,000 BTUs per hour must be 85% AFUE or better. If located in the colder Climate Zones 6, 7 or 8, they must be 90% AFUE or better.Larger hot water boilers (gas or oil-fired) greater than 300,000 BTUs per hour must be 87% efficient or better.If used with water-source heat pumps, those boilers must be 89% efficient or better.
10 Heating Equipment – Minimum Efficiencies for Furnaces For CZ 1, 2, and 3, in-unit warm-air furnaces <225,000 Btuh must be 80% AFUE or greater.For CZ 4&5, in-unit warm-air furnaces <225,000 Btuh must be ENERGY STAR qualified.For CZ 6, 7 and 8, in-unit warm-air furnaces <225,000 Btuh must be 95% AFUE or greater if gas-fired and 90% AFUE or greater if oil-fired.Furnaces <225,000 Btuh serving common areas must be greater than 78% AFUE.Warm-air furnaces ≥225,000 Btuh must be ≥80% Et if gas-fired and ≥81% Et if oil-fired.In the Prescriptive Path, warm-air furnaces in apartments less than 225,000 BTUs per hour in climate zones 1, 2 and 3, don’t have to be ENERGY STAR qualified, but they have to be at least 80% AFUE.Warm-air furnaces in apartments in climate zones 4 and 5 have to be ENERGY STAR qualified.If in climates zones 6, 7 and 8, they have to exceed ENERGY STAR criteria due to their higher heating loads. If gas-fired, they need be 95% AFUE or greater, and 90% AFUE or greater if oil-fired.Common area furnaces less than 225,000 BTUs per hours need to be greater than 78% AFUE and ALL furnaces larger than 225,000 BTUs per hour need to be at least 80% efficient if gas-fired and 81% efficient if oil-fired.
11 Heating and Cooling Equipment – Minimum Efficiencies for PTAC/PTHP Equations based on capacity determine minimum efficiencies for PTACs and PTHPs.Example: PTACEER=13.8-(0.3xCap/1000)“Cap” is capacity and must be a number between 7,000 and 15,000 Btuh.Minimum efficiencies for Package Terminal Air Conditioners and Package Terminal Heat pumps are determined using capacity-based equations.For example, the minimum energy efficiency rating for a PTAC is determined using this formula. If the proposed PTAC is less than 7,000 BTUs per hour, 7,000 must be used in the equation. Similarly, if the proposed PTAC is greater than 15,000 BTUs per hour, 15,000 must be used in the equation.At a capacity of 12,000, this formulas yields a minimum EER of 10.2 as the Prescriptive requirement for a PTAC.
12 Heating and Cooling Equipment - Minimum Efficiencies for ASHPs Air-cooled heat pumps in Climate Zones 1 and 2, must meet or exceed SEER 15 and 8.2 HSPF.They must be ENERGY STAR qualified in Climate Zones 3 to 8.Climate Zones 4-6 have additional HSPF requirements.Dual-fuel for zones 7&8Split-system air-cooled heat pumps between 13,000 BTUs per hour and 65,000 BTUS per hour, must be minimally ENERGY STAR qualified in all climate zones.In climate zone 1 and 2, they must exceed ENERGY STAR criteria with at least a SEER 15 and 8.2 Heating Season Performance Factor.Climate Zones 4-6 have additional HSPF requirements and in climate zones 7 and 8, the ENERGY STAR qualified heat pumps must have dual-fuel backup, rather than electric resistance backup. If heat pumps with electric resistance backup are chosen for the design in those two zones, the Performance Path would need to be selected instead of the Prescriptive Path to earn the ENERGY STAR. Although electric resistance heating is not permitted as a primary heating source in any space in the Prescriptive Path, it is permitted as a back-up heat source to heat pumps in climate zones one through six.
13 Cooling Equipment – Minimum Efficiencies for Split ACs Split system air conditioners in any zone that are less than 13,000 Btuh must be SEER 13 or greater.For Climate Zones 1 and 2, split system ACs must be SEER 16 or greater.For Climate Zones 3, 4 and 5, split system ACs must be ENERGY STAR qualified.For Climate Zones 6, 7 and 8, split system ACs must be SEER 13 or greater.Due to availability, split system air conditioners smaller than 13,000 BTUs per hour do not need to be ENERGY STAR qualified but must meet the Federal Standard of SEER 13.In the Prescriptive Path, due to their larger cooling loads, split system air conditioners for climate zones 1 and 2, have to exceed ENERGY STAR criteria with a SEER 16 or better.Split system air conditioners in climate zones 3, 4, and 5 have to be ENERGY STAR qualified.Due to the smaller cooling load, split system air conditioners in climate zones 6, 7, and 8 only need to meet the Federal Standard of SEER 13.
14 Cooling Equipment – ENERGY STAR or better In all zones, all window, through-wall, and mini-split air conditioners (or heat pumps) must be ENERGY STAR qualified.In ALL zones, all room air conditioners and mini-splits must be ENERGY STAR qualified.
15 Heating and Cooling Equipment- Other Prescriptive Requirements Cooling tower fan motors must be equipped with variable frequency drives that are controlled by a temperature sensor on the condenser water supply pipe.To wrap up the heating and cooling equipment requirements of the Prescriptive Path, if central cooling is provided using a cooling tower, the cooling tower fan motors must be equipped with variable frequency drives that are controlled by a temperature sensor on the condenser water supply pipe.For systems not mentioned in this webinar, please review Table 1 of the Prescriptive Path.15
16 Heating and Cooling Distribution – Ducted Forced Air System Design For in-unit ducted forced air distribution systems, perform design calculations (using ACCA Manuals J and D, the ASHRAE Handbook of Fundamentals, or an equivalent procedure) and install ducts according to design.Flex duct shall follow the Sheet Metal and Air Conditioning Contractors’ (SMACNA) installation standards for flex ducts.Bedrooms must be pressure-balanced.No additional Prescriptive Requirement.Identical to the Performance Path, in-unit ducted forced air distribution systems must be properly designed and installed and all flex duct shall follow SMACNA’s installation standards.Also, bedrooms must be pressure-balanced using any combination of transfer grills, jump ducts, dedicated returns, or properly undercut doors.These are the same Prerequisites in both Paths.
17 Heating and Cooling Distribution – Insulation Heating and cooling supply and return ductwork must be insulated to a minimum R-8 in unconditioned space.Piping carrying fluid or steam with temperatures less than 60°F or greater than 105°F, must have a minimum of 1” of insulation. Pipes over 1.5” in diameter must have a minimum of 1.5” of insulation. (No additional requirement.)Distribution systems, whether hydronic or forced air, have minimum insulation requirements.In the Prescriptive Path, heating and cooling, supply AND return ductwork is increased to a minimum R-8 in unconditioned space. Piping insulation remains the same as the Prerequisite in the Performance Path.17
18 Heating and Cooling Distribution –Sealing and Leakage Heating and cooling ductwork must be sealed at all transverse joints and connections, including ductwork connections through drywall or other finish materials, using UL-181 compliant methods and materials.Total duct leakage for in-unit ducted forced air systems shall be:≤6 CFM25 per 100 ft2 of conditioned floor area for units 1200 ft2 and greater.≤8 CFM25 per 100 ft2 of conditioned floor area for units less than 1200 ft2.Ductwork sealing and allowed leakage amounts are also the same as the Prerequisite in the Performance Path.Duct sealing must utilize UL-181 compliant methods and materials and total duct leakage amounts must be tested to be less than either 6 or 8 CFM per 100 square feet of conditioned floor area, depending on the size of the apartment.
19 Heating and Cooling Distribution ControlsThermostatsOutside air dampersHydronic designNo additional Prescriptive Requirement.The remaining Prescriptive Requirements related to heating and cooling distribution (controls, thermostats, outside air dampers and hydronic design) are all the same as the Prerequisites in the Performance Path, and details can be found in the Prescriptive Path document.19
20 Envelope – Air Barrier & Infiltration The building plans shall demonstrate a continuous, unbroken air barrier separating the conditioned space of the building from the exterior and other unconditioned or commercial spaces.Apartments shall be sealed to reduce air exchange between the apartment and exterior as well as the apartment and adjacent spaces.A maximum air leakage rate of 0.30 CFM50 per square feet of enclosure is allowed.Also identical to the Prerequisites in the Performance Path, buildings following the Prescriptive Path must demonstrate a continuous unbroken air barrier and apartments must be tested for air leakage, which cannot exceed 0.30 CFM50 per square feet of enclosure. As a reminder, the enclosure includes all surfaces, floor, ceiling, party walls and exterior walls.
21 EnvelopeThe envelope components must comply with ASHRAE , Section 5.4.See Tables 2 and 3 of the Prescriptive Path for minimum R-values and maximum assembly U-values per ASHRAE climate zones.Similar to the Mandatory Provisions of ASHRAE that applied to the heating and cooling equipment, the envelope components must comply with ASHRAE , Section A one-page checklist is provided by ASHRAE to help design teams confirm whether or not they are in compliance with these provisions, but is not required for submission to the EPA.This is the same Prerequisite as in the Performance Path.Rather than follow the U-value requirements in ASHRAE , the Prescriptive Path requirements are based on ASHRAE , Standard for the Design of High-Performance, Green Buildings. These minimum R-values and maximum U-values are provided in Tables 2 and 3 of the Prescriptive Path, according to climate zone.
22 Envelope – Climate Specific Requirements RoofAbove-Grade WallsBelow-Grade WallsFloorsSlabsUnheatedHeatedExterior DoorsVertical GlazingNonmetalMetalTables 2 and 3 list the climate-specific minimum R-values and maximum U-values for roofs, above-grade walls, below-grade walls, floors above unconditioned spaces, slabs on grade, slabs below grade, slabs with radiant heat, exterior doors, nonmetal framed windows and metal framed windows.
23 Envelope – Climate Specific Requirements For example, an attic in Climate Zone 5 would prescriptively need R-49 in between roof rafters.If selecting another insulation method, the U-value of the roof assembly cannot exceed UFor example, an attic in Climate Zone 5 would prescriptively need R-49 nominally rated insulation in between roof rafters.Alternatively, you can follow the U-value rather than the R-value. For example, if selecting another insulation method, perhaps lower cavity insulation, but additional continuous, the U-value of the roof assembly cannot exceed
24 Envelope – U-values, Insulation Grade U-value determinations must follow ASHRAE , Appendix A.An area weighted average of the U-values of the wall and floor perimeter assemblies is acceptable.RESNET-defined Grade I insulation installation or Grade II if combined with continuous insulation (≥R-3 in CZ 1-4 and ≥R-5 in CZ 5-8).No additional prescriptive requirement.Although there is no energy model in the Prescriptive Path, U-value determinations must still follow ASHRAE , Appendix A.The area weighted average of the U-values of the wall and floor perimeter assemblies is still acceptable for comparing to the requirements in Tables 2 and 3 for the above-grade wall.Insulation that is installed must still meet RESNET Grade one criteria, unless installed in conjunction with an appropriate amount of continuous insulation, in which case Grade two would be permitted.These are the same requirements as the Prerequisites in the Performance Path.
25 Envelope – Vestibules & AC sleeves When required by local building code, entranceways shall be designed with vestibules with weather-stripping hard-fastened to the door or frame.Insulated covers (R-7 or higher) for through-wall AC units must be provided by the building for use during the heating season or when AC units are not installed.No additional prescriptive requirement.Identical to the Performance Path, if your local building code requires that entranceways be designed with vestibules, the vestibules must have weather-stripping hard-fastened to the door or frame.And, if your building utilizes through-wall air-conditioners for cooling, insulated covers, R-7 or higher, must be provided by the building for use during the heating season or when AC units are not installed.
26 Envelope – Walls & Windows For steel-framed and metal buildings, continuous exterior insulation is required.For masonry buildings with metal framing, continuous interior or exterior insulation is required.Specified windows must be double or triple-pane, with low-e glass or coatings.Maximum allowable window to wall ratio: 30%In addition to meeting the climate specific envelope requirements from Tables 2 and 3, to reduce thermal bridging, continuous exterior insulation is required for steel-framed and metal buildings.For masonry buildings with metal framing, continuous interior or continuous exterior insulation is required. This is the same requirement as in the Performance Path.Beyond meeting the window U-value and solar heat gain coefficients from Tables 2 and 3, windows must still be double or triple pane with low-e glass or coatings.In addition, total window area is limited in the Prescriptive Path to 30%. This means that no more than 30% of the gross exterior above grade wall area can be glazing. Buildings with higher window to wall area ratios can pursue the ENERGY STAR in the Performance Path.
27 Garages and Sidewalks Garages shall be fully compartmentalized. All pipe & conduit penetrations shall be sealed.Garages shall not be heated for comfort or to prevent pipes from freezing.Radiant heating, either wall or ceiling-mounted or within the garage floor (or sidewalks) may be used to prevent ice formation on the ground as a safety feature only.When exhaust is required by code, CO sensors must be installed to control operation.The prerequisites that apply to garages and sidewalks are the same in the Prescriptive Path. Garages must be properly air-sealed and heating can only be used as a safety feature to prevent ice formation on the ground and not to prevent pipes from freezing. If the design cannot meet this requirement, the building cannot earn the ENERGY STAR through EITHER path.The one additional requirement in the Prescriptive Path is that when mechanical exhaust is required in the garage by local code, carbon monoxide sensors must be installed that control exhaust fan operation and prevent them from operating when there is no need for ventilation. Although the ventilated air does not represent a loss of conditioned air, the electricity consumed by these large exhaust fans can be greatly reduced by using these sensors.
28 Ventilation – ASHRAE 62 requirements Common area ventilation systems shall be designed and tested to satisfy minimum requirements of ASHRAEApartment ventilation systems shall be designed and tested to satisfy minimum requirements of ASHRAE based upon the anticipated occupancy.Measured rates cannot exceed ASHRAE rates by more than 50%.Identical to the Prerequisite in the Performance Path, common area ventilation systems shall be designed and tested to satisfy minimum requirements of ASHRAE and apartment ventilation systems shall be designed and tested to satisfy minimum requirements of ASHRAEProviding dedicated outdoor air to each unit is still recommended, but not required and kitchen exhaust must still be vented to the exterior.The additional requirement of the Prescriptive Path is that measured rates cannot exceed ASHRAE by more than 50%. Over-ventilation consumes extra energy which can be captured through energy modeling in the Performance Path, but not in the Prescriptive Path.
29 Ventilation – Duct sealing & Leakage Ventilation system ductwork must be sealed at all transverse joints and connections including boot to wall/ceiling connections through drywall using UL-181 compliant materials and methods.Ductwork penetrations must be sealed at the roof curb to prevent air leakage through the duct system and/or the building envelope.Central exhaust systems must be tested for duct leakage, which cannot exceed 5 CFM50 per floor per shaft. See T&V Protocols for details.In the Prescriptive Path, all ventilation ductwork must still be properly sealed and central exhaust systems are still tested for leakage, however the amount of leakage allowed in the Prescriptive Path is cut in half compared to the Performance Path.
30 Ventilation – Controls Central exhaust fans ≤ 1/16 HP must be direct-drive and have variable speed controllers.Central exhaust fans between 1/16 and 1 HP must be direct-drive with ECM motors and variable speed controllers.Central exhaust fans 1 HP and larger must have NEMA Premium efficient motors.All the ventilation control requirements on this slide are only applicable to projects in the Prescriptive Path.Central exhaust fans 1/16 horsepower and less must be direct-drive and have variable speed controllers.Central exhaust fans greater than 1/16 horsepower and less than 1 horsepower must also be direct-drive with variable speed controllers but must also have ECM motors.Central exhaust fans 1 horsepower and larger must simply have NEMA Premium efficient motors. NEMA motors are not sufficient, they must be NEMA PREMIUM.These requirements not only reduce the amount of energy consumed by the exhaust fans, but can make the balancing process easier.
31 Ventilation – Controls, continued Central exhaust and in-line exhaust systems serving apartments must have self-balancing dampers at each grille.Powered common laundry ventilation must be installed with automatic demand control to turn off ventilation fans when no dryers are operating. These ventilation control requirements are also just applicable to projects in the Prescriptive Path.Central exhaust and in-line exhaust systems serving apartments must have self-balancing dampers at each grille. These dampers prevent the stack effect from impacting the amount of ventilation exhausted from a space by automatically moderating how much air can be ventilated through the grille.Ventilation serving common laundry rooms must be installed with automatic demand control to turn off ventilation fans when no dryers are operating. This can significantly reduce energy consumption as this reduces both electricity consumed by the ventilation fans and the thermal loss from the continual and unnecessary ventilation of this space.
32 Domestic Water Heating – ASHRAE Mandatory Provisions Domestic water heating systems must comply with ASHRAE , Section 7.4 and 7.5.Domestic water heating systems in the Prescriptive Path must still comply with ASHRAE , Section 7.4.In addition, the requirements of Section 7.5 must also be met. Similar to before, a checklist is available to help the design team confirm compliance with these sections, but is not required to be submitted to the EPA.
33 Domestic Water Heating – Minimum Efficiencies Domestic water heating equipment shall be ENERGY STAR qualified, where applicable.Minimum Efficiencies:Hot Water Supply Boiler (oil or gas): 85% EtIn-Unit Storage or Instantaneous:Gas (EF): 0.69-(0.002 x Tank Gallon Capacity)Electric (EF): 0.97-(0.001 x Tank Gallon Capacity)Domestic water heating equipment shall be ENERGY STAR qualified, where applicable. Not all systems found in multifamily high rise buildings are eligible for the ENERGY STAR label, since that program tends to apply to residential equipment used in single family homes. Where available, they should be ENERGY STAR qualified.Minimum efficiencies are therefore established as follows:For hot water boilers, gas or oil-fired, in-unit or central, the minimum efficiency allowed in the Prescriptive Path is 85% Et.For in-unit tankless or storage water heaters, these equations determine the minimum efficiency. For example, a 50 gallon gas storage water heater must have an energy factor of at least Since storage water heaters are readily available as ENERGY STAR qualified, this minimum will generally be exceeded due to the higher criteria for ENERGY STAR qualified water heaters.To determine minimum efficiencies for tankless systems, use 1 gallon for Tank Gallon Capacity.
34 Domestic Water Heating - Type Atmospherically vented gas water heaters, tankless coils and side-arm water heaters shall not be specified.If storage is provided, the maximum storage tank capacity shall be specified based on occupancy.The next two slides review Prescriptive requirements that are the same as the Prerequisites from the Performance Path.Atmospherically vented gas water heaters, tankless coils and side-arm water heaters shall not be specified.If storage is provided, the maximum storage tank capacity shall still be specified based on occupancy.
35 Domestic Water Heating – Temperature and Pressure Self-contained or electronic mixing valves shall be used to control hot water temperature for central domestic water heating systems.The temperature of the stored hot water shall be just sufficient to deliver water to apartments within a temperature range of °F.Self-contained or electronic mixing valves shall still be used to control hot water temperature for central domestic water heating systems. Mechanical tempering valves are still not permitted.The temperature of the stored hot water shall be just sufficient to deliver water to apartments within a temperature range of °F.This delivery temperature is verified during inspections.
36 Domestic Water Heating – Low Flow All lavatory faucets or aerators must be WaterSense labeled.The average flow rate for all other faucets must be ≤ 2.00 gpm.The average flow rate for all showers must be ≤ 1.75 gallons per minute per stall and all showerheads must be WaterSense labeled.All tank-type toilets must be WaterSense labeled.The Prescriptive Path reduces the average flow rate allowed for lavatory faucets and showers.Lavatory faucets and aerators must now be WaterSense labeled.This still enables kitchen faucets to have slightly higher flow rates than bathroom faucets since they remain at 2.0 gallons per minute, with no labeling requirement.Showers, even those with multiple showerheads, are now limited to 1.75 gallons per minute for the entire shower stall. The WaterSense labeling requirement for the actual showerheads is the same as the Performance Path.The same requirement for low-flow toilets remains, they must be WaterSense labeled.
37 Lighting Lighting must comply with ASHRAE 90.1-2007, Section 9.4. 80% of installed light fixtures must be ENERGY STAR qualified or have ENERGY STAR qualified lamps (bulbs) installed.Lighting must be designed to meet light levels (footcandles) by space type as recommended by the Illumination Engineering Society (IESNA) Lighting Handbook, 9th edition.In the Prescriptive Path, lighting must still comply with ASHRAE , Section 9.4. Similar to before, a checklist is available to confirm compliance with these mandatory provisions.At least 80% of installed light fixtures must still be ENERGY STAR qualified or have ENERGY STAR qualified lamps installed and the energy efficient lighting in each space must still be designed to meet proper light levels. A footcandle is equivalent to one lumen per square foot.
38 Lighting – Footcandles (lumen/ft2) ASHRAE Space TypeLighting Power Densities (W/ft2)Recommended Light Levels (Weighted Avg. Footcandles)ASHRAE SpaceTypeApartments0.75*16Stairway0.6915Storage0.6320Restroom0.9812Elevator0.64Office (enclosed/open)1.11/0.9835Food Preparation0.9940Conference/meeting/multipurpose1.2330Dining Area - For Family Dining0.8923Electrical/Mechanical0.95Lobby0.90Workshop1.5950Corridor/Transition0.6610Parking garage0.197The Illuminating Engineering Society’s footcandle recommendations for spaces commonly found in multifamily high rise buildings have been listed for your convenience in both the Prescriptive and Performance Path documents and is shown on this slide.Once you have the proposed lighting schedule and fixture specifications, the Performance Path calculator has a worksheet that will help you determine if light levels have been met. This worksheet can ALSO be used if following the Prescriptive Path. The Performance Path Calculator is an Excel-based worksheet used in the Performance Path and available for download from our website. There is also a webinar that demonstrates how to use it.
39 Lighting – Common Areas All non-apartment spaces, except those where automatic shutoff would endanger the safety of occupants, must have occupancy sensors or automatic bi-level lighting controls. Automatic controls are required in 24-hour areas such as corridors and stairwells.Total installed lighting power for the combined common spaces should not exceed ASHRAE allowances for those combined spaces.Common areas, or non-apartment spaces, have additional lighting requirements if following the Prescriptive Path.The prerequisites already require that these common spaces have either occupancy sensors that turn lighting on and off based on motion, or bi-level lighting controls that allow for low level lighting until triggered, and then provide lighting at full capacity.If following the Prescriptive Path, these sensors are not required in spaces if automatic shutoff or low-level lighting would endanger the safety of the occupants. They are however required in spaces intended for 24-hour operation such as corridors and stairwells. Generally if emergency lighting is required by local code to remain on for 24 hours, this requirement can be met by using sensors on the fixtures not designated as emergency.These common spaces are also subject to a prescriptive requirement that limits the amount of lighting installed. The total installed lighting power for the combined common spaces should not exceed ASHRAE allowances for those combined spaces. The Performance Path allowed an excess of up to 20% over this is not permitted in the Prescriptive Path.
40 Lighting – ASHRAE 90.1-2010 Lighting Power Densities (LPDs) ASHRAE Space TypeLighting Power Densities (W/ft2)Recommended Light Levels (Weighted Avg. Footcandles)ASHRAE SpaceTypeApartments0.75*16Stairway0.6915Storage0.6320Restroom0.9812Elevator0.64Office (enclosed/open)1.11/0.9835Food Preparation0.9940Conference/meeting/multipurpose1.2330Dining Area - For Family Dining0.8923Electrical/Mechanical0.95Lobby0.90Workshop1.5950Corridor/Transition0.6610Parking garage0.197As you can see in this Table, the lighting power densities, or LPDs, from ASHRAE have been listed for common spaces frequently found in multifamily high rise buildings. This table is located in the Notes section of the Prescriptive Path document.Apartment dwelling units are not listed as a space type in ASHRAE, so the lighting power density for highway lodging guest rooms was used instead.Multiplying the lighting power density by the square footage of a given space type, determines the ASHRAE allowance for that space.For example, a 1,000 square foot corridor would have a lighting allowance of 660 Watts.Summing the allowances for all the common area spaces gives you the COMBINED allowance.EPA will allow any individual space to exceed their lighting allowance, as long as the sum of the installed lighting power for ALL the common spaces combined does not exceed the combined baseline allowance and illumination requirements are still met.This prescriptive requirement allows flexibility in selecting light fixtures, while limiting over-lighting of common spaces.Unlike the Performance Path, the Prescriptive Path has a maximum lighting allowance identified for apartments, which is 0.75 Watts per square foot.
41 Lighting – Calculations The requirement of ASHRAE , Section 9.1.4a, that light fixtures MUST be calculated with the maximum labeled wattage of the fixture is not required.Example: A fixture with a 13 W screw-in CFL can be modeled as 13 W, plus any associated ballast power. See Appendix B of Prescriptive Path for suggested ballast power.To calculate lighting power densities in your building, you can use the Lighting worksheet available in the Performance Path calculator.Although ASHRAE requires that light fixtures be modeled with the maximum labeled wattage of the fixture, REGARDLESS of the type of lamp installed, the EPA does not.According to ASHRAE, a light fixture that has a maximum rated wattage of 100 Watts, must be modeled as 100 Watts, even if a much lower Watt lamp is installed.This is not a requirement in the MFHR program so that buildings with energy efficient lighting can account for savings associated with the installed lamps, regardless of the fixture installed.For example, a fixture with a 13 Watt screw-in CFL can be calculated as 13 Watt, plus any associated ballast power, even if the fixture is rated for up to 100 Watts. If ballast power is not known, see Appendix B of the Prescriptive Path for suggested ballast power.
42 Lighting – Calculations inside Units Overall in-unit lighting power density may not exceed 0.75 W/ft2.Use 1.1 W/ft2 for areas inside units where lighting is not installed (ex. Living rooms and bedrooms that use switched outlets).Use data from light fixtures to calculate LPD of spaces where lighting is installed and take the weighted average to get the overall LPD.In spaces where supplemental lighting will be needed, installed fixtures may only illuminate up to 2 ft2 per Watt.As mentioned previously, overall in-unit lighting power density may not exceed 0.75 Watts per square foot. For example, bathrooms can have higher lighting densities if other spaces inside the unit can compensate for it, while still providing enough illumination.To calculate the overall lighting power density inside a unit, use 1.1 Watts per square foot for areas inside units where lighting is not installed, such as living rooms and bedrooms that use switched outlets.Use data from light fixtures to calculate lighting power density of spaces where lighting is installed and then take the weighted average to get the overall lighting power density.In spaces where some fixtures are installed but occupant-provided supplemental lighting will be needed to meet footcandle requirements, the fixtures that are installed by the builder may only account for illuminating up to 2 square feet per Watt installed.
43 Lighting – Calculations inside Units BR1 – 150 ft2Kitchen ft2Bath – 50 ft2Hall – 100 ft2This floorplan is not drawn to scale, but demonstrates the calculations.The total square footage of the apartment is 950 square feet.If providing lighting in each space that will fully provide illumination for each space without the need of supplemental lighting, no more than 712 Watts may be installed if following the Prescriptive Path.Each room does not need to meet the 0.75 Watts per square foot requirement, as long as the overall lighting power density does not exceed it.This prescriptive requirement can be used as a guideline for selecting fixtures. For example, a 50 square foot bathroom should target about 37 Watts to maintain that lighting power density.Living Room- 300 ft2BR2 – 150 ft2950 ft2 x 0.75 Watts/ft2 = 712 Watts
44 Lighting – Calculations inside Units BR1 – 150 ft2Kitchen ft2Bath – 50 ft2Hall – 100 ft2Living Room- 300 ft2If a room has a fixture installed, but it is not intended to provide full illumination for the space, then supplemental lighting will need to be provided by the occupant.That supplemental lighting must be calculated as 1.1 Watts per square foot.The installed lighting can only apply to 2 square feet per Watt of installed lighting.So, if 100 Watts of energy efficient lighting is installed in the 300 square foot living room, it can at most illuminate 200 square feet, leaving 100 square feet to be lit by supplemental lighting provided by the occupant. It cannot be assumed to light the entire 300 square feet.Unlit area –100 ft2, assume 110 W supplied by occupantLit area –200 ft2, 100 W installedBR2 – 150 ft2
45 Lighting – Exterior80% of outdoor lighting fixtures must be ENERGY STAR qualified or have ENERGY STAR qualified lamps installed.Fixtures must include automatic switching on timers or photocell controls except fixtures intended for 24-hour operation, required for security, or located on apartment balconies.Total installed exterior lighting power cannot exceed ASHRAE allowances.Similar to indoor lighting requirements, 80% of the exterior light fixtures must be ENERGY STAR qualified or have ENERGY STAR qualified lamps installed.Exterior lighting fixtures must include automatic switching on timers or photocell controls. Fixtures intended for 24-hour operation, required for security, or located on apartment balconies do NOT have to meet this requirement.These are the same requirements as in the Performance Path. The one additional requirement is that the total installed exterior lighting power cannot exceed ASHRAE allowances.
46 Lighting – Exit SignsAll exit signs must be specified as LED (not to exceed 5W per face) or photo-luminescent and must conform to local building code; fixtures located above stairwell doors and other forms of egress must contain a battery back-up feature.Identical to the Prerequisites in the Performance Path, exit signs are not included in the 80% ENERGY STAR requirement, however they must be specified as either LED, with no more than 5 Watt per face, or photo-luminescent. They must also conform to local building code and contain battery back-up where needed.
47 Pump Motor EfficiencyAll three-phase pump motors 1 HP or larger shall meet or exceed efficiency standards for NEMA Premium™ motors, where available.Many motors are NEMA labeled and this label alone, does not ensure that a motor is energy-efficient. This requirement refers specifically to the NEMA Premium energy efficient motors program.Motors 5 HP or larger for circulating pumps serving hydronic heating or cooling systems must be specified with variable frequency drives.Pump motor efficiency – the program prerequisite requires that three-phase pump motors 1 horse-power or larger shall meet or exceed efficiency standards for NEMA Premium™ motors, where available. Single phase pump motors or pump motors smaller than 1 horsepower, do not need to meet this prerequisite.This requirement is the same for the Prescriptive Path and refers specifically to the NEMA Premium energy efficient motors program.In addition, for buildings following the Prescriptive Path that have hydronic heating or cooling systems, any motors 5 horsepower or larger for circulating pumps serving those hydronic systems must be specified with variable frequency drives.
48 MeteringThe commercial/retail parts of the building shall be separately metered or sub-metered for electricity, gas, fuel oil, water, and steam, where applicable.The building owner must secure signed utility bill releases from individual apartment occupants to allow for benchmarking or obtain whole-building consumption data from their local utility.The building owner must provide a signed release for the common area/whole-building utility meters.Metering is the final prerequisite and is the same as in the Performance Path.As part of their Participation Agreement, the developer of the building commits to benchmarking the energy use of the building for a minimum of two years after construction is complete.To facilitate this process, in mixed-use buildings, the commercial and retail spaces must be separately metered for all fuel sources and water.The building owner commits to collecting utility bill releases from as many occupants as possible and provides a release for any building level meters or meters serving common areas. If obtaining tenant release forms and extrapolating the data is problematic, some local utilities may offer a service where they can aggregate the consumption data at the building level, for a fee. Alternatively, whole-building utility meters can be installed for a fee that record whole-building consumption.
49 Testing and Verification Buildings following the Prescriptive Path must also follow the Testing and Verification Protocols.These protocols are the mandatory requirements for the inspection, testing and verification of components related to the building’s energy performance.The intent of the protocols is to verify thatthe construction documents & final building include all Prerequisites and Prescriptive requirements.measures have been installed and perform as expected.The other common requirement of both paths is verification and performance testing.The Testing and Verification protocols establish a consistent set of requirements for the inspection, testing and verification of components related to the building’s energy performance.The intent of the protocols is to verify that both the construction documents and the final building include all Prerequisites, Prescriptive requirements and that measures installed perform as expected.
50 Testing and Verification Changes to the initial design noted during inspections must be reflected in the revised T&V Worksheets and submitted at the end of construction.All Prescriptive requirements must still be met in order to earn the ENERGY STAR. If any are not met, an As-Built energy model could be used to earn the ENERGY STAR, if it meets the 15% Performance Target and Prerequisites.The T&V Worksheets and Photo Template must be submitted as they document the results of all mandatory testing and verification.Any change in design during construction must be accounted for in the final T&V Worksheets.If changes occur during construction that cause the building to not meet a Prescriptive requirement, the building will not earn the ENERGY STAR. The developer has the option at that point to switch to the Performance Path and develop an energy model that represents the As-Built conditions. If this As-Built model meets the 15% energy cost savings Performance Target and all Prerequisites, it can still earn the ENERGY STAR.The EPA requires that the T&V protocols be documented throughout the course of the project, beginning with plan reviews during the design stage. The Testing and Verification worksheets must be submitted and approved twice, once prior to construction and once after construction is complete. The Photo Template gets submitted once, after construction is complete.A separate webinar is available that explains the Testing and Verification protocols and how to document them.
51 Prescriptive Path Components PrerequisitesPrescriptive RequirementsTesting and Verification (T&V)BenchmarkingWe’ve reviewed almost all of the components of the Prescriptive Path.The final component is using Portfolio Manager to Benchmark your building’s energy use. Webinars are available on our website that will guide you through this process.
52 Prescriptive Path Steps Apply to Program; become PartnerMeet Prerequisites & Prescriptive requirementsReview plans, submit T&V worksheets to EPABuild according to DesignConduct Testing and VerificationSubmit T&V worksheets and Photo Template to EPAEarn ENERGY STARBenchmark for two yearsAs we conclude this webinar, let’s review the steps to follow if selecting the Prescriptive Path.First, the developer needs to apply to the program and sign the partnership agreement.A registered architect or professional engineer works with the design team to ensure the design meets prerequisites and the additional Prescriptive requirements.The results of plan reviews and the signed Prescriptive Checklist are submitted to the EPA using the T&V Worksheets.The building is constructed according to design, and throughout construction every component is verified and documented, and performance testing is conducted.At the end, the updated worksheets and photo template are submitted to the EPA, and if all requirements have been met, the EPA will approve the building to earn the ENERGY STAR.Finally, the developer must follow through on their commitment to benchmark the building energy use for two years.
53 Contact: MFHR@energystar.gov The EndQuestions?Contact:If you have questions about the Prescriptive Path, please visit our website for more information or us.