Fall$ 08! HighPerformance%Building%Guidelines%

High Performance Building Guidelines 2nd Edition

Fall 14

08 Fall

JHU High Performance Building Standards

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Introduction

This guide was assembled with input from each of the Johns Hopkins University’s Schools, Divisions and Campuses. It will assist designers, project managers and maintenance technicians to improve sustainable energy designs, their implementation and operations. This will more clearly communicate our energy and water reduction goals for construction, building materials, equipment and systems, and operational and maintenance needs to both internal stakeholders and to our design consultants. The Office of Sustainability has collaborated with our campus Design and Construction, Project Management and Facilities Operations staff to identify areas needing improved sustainable choices.

Improving our sustainable efforts challenges each of us to identify and implement the most environmentally friendly, financially sound and socially acceptable solutions for our institution. These initiatives will reduce our Greenhouse Gas emissions, water consumption and waste generation. Many of these opportunities will result in more efficient buildings, equipment and systems, intended to save energy and operating expenses. No initiatives should compromise the user’s comfort, productivity or safety.

Questions or comments about this guide? Please contact Ed Kirk, the University Energy Manager at 443-‐997-‐2343 or [email protected].


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Table of Contents

1. Guiding Principles a. Using this Guide b. Energy Reduction c. Greenhouse Gas Reduction Goals d. LEED and Building Energy Codes

2. Tools and Benchmarks a. Financial Evaluation b. Metering & Measuring Performance c. Energy Modeling d. Audits and Inspections e. Commissioning f. LEED, Energy Star, IGCC and Energy Code g. Utility Incentives and Rebates

3. Building Envelope a. Roofing b. Windows and Doors c. Thermal Insulation

4. Mechanical Equipment and Systems a. Heating and Hot Water b. Ventilation and Cooling c. Domestic Water d. Elevator e. CHP f. Controls (BAS, BMS, ATC, EMS) g. Dashboards

5. Electrical Equipment and Systems a. Service, Transformers and Distribution b. Emergency Power c. Lighting d. Lighting Controls e. Plug Loads

6. Specific Space Types a. Data Centers b. Research spaces c. Cooking Facilities d. Mechanical and Electrical spaces e. Tel/Data Closets f. Mobile Equipment

7. Renewable Energy a. Solar PV b. Solar Thermal c. Wind d. Bio Fuels

8. References


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Guiding Principles

Using this Guide: The information contained here is intended to apply to all projects that touch building systems that consume energy or water, regardless of project budget or square foot impact. Using progressive ways of providing for capacity, redundancy, reliability and future flexibility, so every project or renovation moves JHU toward its overall goals. Verify through proper installation, set-‐up and commissioning that the thermal envelope and all building components and systems are working optimally.

Energy & Water Reduction Goals: Each project should set a goal to be designed to use 30% less energy and water than allowed by the latest published codes. Projects effecting energy use should perform some sort of energy modeling and use Life Cycle Cost Analysis, when possible, to compare project options, enabling design teams to make informed decisions. All project options that pay for themselves in less than half their life expectancy should be brought to the design team’s attention for serious consideration. This means that financial analysis that considers total cost of ownership (Life Cycle Cost Analysis) must be performed. Do not allow systems to become overly complex, costly to install or difficult to maintain. Build in the ability for automatic tune-‐ups, fault detection and performance verification using “dashboards” and smart phone apps. Ensure a healthy, productive and safe environment for the building’s occupants.

Greenhouse Gas Reduction: Our University goal to reduce our GHGs by 51% by 2025 need to be measurable. Real-‐time metering is required on all energy and water systems to regularly verify performance and progress toward our reduction goals.

LEED and Building Energy Codes: We wish to create the healthiest, most productive work environments possible. When conflicts occur between building and energy code requirements, we insist upon open dialogue amongst the design team and the JHU owner representatives so we are sure we are meeting the end user’s needs, the intent of the codes and not just the letter of the codes.


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Tools and Benchmarks

Financial Evaluation: Energy code enhancements have forced designers and operators to pay more attention to project budgeting. Even more important than a project’s initial design and construction funding, and regardless of size, are energy code limits and impacts to operating costs over their expected life. While the use of first cost estimating is a simple tool when developing initial project budgets, today’s budgets must include energy code compliance. Life Cycle Cost Analysis must be used for “Value Engineering” cost cutting options that could impact energy and water use, storm water mitigation or other long term environmental factors.

Measuring Performance: Each building requires utility metering to track energy and resource use. At a minimum metering is required for electrical, gas, oil, water, steam and chilled water. For new construction and major renovations, and where applicable to major alterations to the system infrastructure, sub-‐metering is also needed on domestic hot water make-‐up, irrigation, cooling tower, boiler make-‐up, gray water system inputs, lighting, HVAC and building equipment, and plug loads.

Energy Modeling: Full modeling is required for all new construction and major renovations. Some energy modeling is also required for any renovations that alter mechanical or electrical systems. Energy modeling should reflect how the spaces and systems will operate once occupied. Models are the tool needed to perform Value Engineering or for obtaining utility rebates. The Energy Use Intensity (EUI) calculation from energy model will be compared to similar space use types. If planning a renovation, model should show existing pre-‐renovation consumption, the latest ASHRAE 90.1 code limit and estimated post-‐renovation consumption.

Listed below are some Energy Use Intensities (EUI) in site KBTU/gsf/yr. This table will assists the design team to understand what limits exist to beat JHU’s goal of 30% less energy use.

Building Type JHU ’09 Avg EUI ASHRAE 90.1 2010 JHU <30% Goal JHU small renovation Goal

Office 90 37.1 26 50

Classroom 169 39.8 28 55

Data Center PUE 2+ 1.1 1.2-‐1.3

Library 124 55 39.5 60

Research Facility (Bio) 357 148 105 225

Research Facility (other) 216 125 88 175

Residence Halls 112 66.6 47 75


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Audits and Inspections: Understand what the existing energy impact is and what the opportunities are. Modifications made and retraining of occupants will need periodic follow-‐up. Commissioning: Some level of commissioning input is required during design, construction and occupancy for all projects that effect energy or water systems. Do not allow systems to become overly complex, costly to install or difficult to maintain. Insist on a continuous commissioning process and easy to verify performance “dashboards” accessible to the occupants or stakeholders. Ensure a healthy, productive and safe environment for the building’s occupants. Utility Incentives & Rebates: Ensure estimates and calculations to obtain utility rebates or other incentives are incorporated in the cost estimates anytime lighting or MEP systems will be impacted.

Building Envelope

New Building Siting: Look at building as a system and review orientation and landscape elements

Roofing and re-‐roof with an average R-‐38 insulating value, including skylight values, and use topcoat with a Reflectivity > 30%. Surface should strive for 3 year aged Solar Reflective index of > 64 per ASTM E 1980. When re-‐roofing we ask that the following considerations be met:

• Roofing system minimum value of R-‐30, except within 3 feet of roof drains. • Roofing have a minimum pitch of 1/4 inch per foot and zero standing water. • Minimum curb and flashing heights of 9 inches. • The entire roofing system have an expected life (not to be confused with warranty) of 30

years. • The roof design and equipment lay-‐out will allow for renewable energy, storm water

mitigation or heat island mitigation. • The roof can withstand foot traffic of typical tradesmen, severe weather events and bird

activity without reducing it's life. • Tear-‐off must be recycled and new roofing system must use sustainable and recyclable

materials.

Exterior walls average insulation R-‐20 including window and door values.

Windows and Doors: Storefronts and Glazing with a

• low E <0.03 • U of <0.3 (total window) • Visible Transmittance > 0.7 • <10% light reflective


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• SHGC <0.3 • thermally broken frames and doors. • air leakage is limited to <1 cfm/sf for doors and <0.2 cfm/sf for windows and skylights.

Skylights:

• Skylights must have a U value no greater than .50 and a SHGC no greater than .40 per AAMA A440-‐11 tests and NFRC labeled (IECC 2012). • IECC 2012 calls for a 3% maximum of the roof area to be lit with skylights. If the building is equipped with automatic day lighting controls you may increase that to 5%. • There are also new minimum top lighting requirements (50% of the floor area must be lit), for top floors of buildings with ceiling heights over 15 feet. This applies to office, lobbies, atriums, concourses, corridors, storage, gyms and warehousing.

Mechanical Equipment and Systems

Heating Systems: Boilers, furnaces and water heaters should have energy efficiency >95%, or in the top 3% for energy efficiency for their class of equipment. Design HHW system to match boiler peak efficiency, and for 140F max (use 5F OA for design calculations) and use OAT reset control. Where possible, use available waste heat to pre-‐heat returning hot water, preheat make-‐up for domestic hot water, preheat AHU inlet air in winter and to reheat supply air after mechanical dehumidification. Use systems that employ variable flows to respond to demand. Consider modular equipment designs to ensure capacity, redundancy and reliability. Consider how to integrate building level Combined Heat and Power (CHP) or Cogeneration anytime heating system or its replacement is considered. Ground Source Heat pump and Hybrid Systems should also be evaluated. Heating systems should be designed to allow for maximum system efficiencies.

Steam Use in Buildings: All steam conversion equipment must be at least 98% thermally efficient. Where possible, use steam at plant pressure for energy conversion equipment, eliminating the need for costly pressure reducing stations and their associated energy losses, flash tanks, and relief valves and associated exit piping, and reducing pipe and heat exchanger sizes. If some research or unique specialty equipment operates on reduced steam pressure, use reducing/control valves at the point of use. Use enthalpy wheels or point of use ultrasonic humidifiers instead of steam humidifiers in air handlers. Do not use clean steam generators when plant steam is available. Properly manage high pressure drip condensate with heat exchangers, all effort should be taken to avoid the use of flash tanks, and venting steam or condensate to atmosphere anywhere in the system. This applies to building and infrastructure renovations. It is desired to capture 100% of steam condensate, extract the maximum heat possible and send it back to the plant at less than 100F. See drawing 1 below.


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Domestic Hot Water systems: Use instantaneous, point of use, water heaters where low flow (<1.0 gpm) devices are used. If tying any sinks into a recirculating hot water system ensure loop water can be delivered to any fixture within 6 seconds of activation . When a water heater is required, use greater than 95% efficient, instantaneous, fully modulating capability for varied flow and variable make-‐up water temp. Consider using waste heat to preheat make-‐up water to hot water heaters. Use demand control on circulating pumps.

Drawing 1

Thermal Insulation: Steam, Hot water and Chilled water Systems: Plant steam will be between 300 and 375F. 2012 IECC Section C403.2.8 requires all parts of these systems with flow through them be insulated. This includes flanges, strainers, valves, expansion joints, etc., which may have removable insulation. ASHRAE 90.1 2010 allows insulation with either conventional insulation or removable/reusable insulation blankets and requires thicker insulation for all temperature ranges and


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on all parts of the systems touching fluid flow (see Table 1 below). According to OSHA non-‐insulated surface temperatures need to be below 120F. Adding a layer of insulation to existing insulation on lines and fittings is often more cost effective than removing and reinsulating those systems. Chilled water systems can have no exposed surfaces and insulation must be vapor-‐tight to prevent condensation.

Ventilation & Air Conditioning Equipment: Effort shall be taken in design and controls to eliminate systems that allow simultaneous cooling and reheating. Employ less energy intensive ways of dehumidification than using conventional chilled water coils with hot water reheat.

Air Handlers: Evaluate the use of enthalpy wheels or smart run-‐around coils to precondition make-‐up air with energy from exhaust air. Consider Heat-‐Pipe or wrap around coils for chilled water coil to pre-‐cool and re-‐heat. Use >Merv 12 filtering prior to the first coil, direct drive fans, enthalpy control, reset temperature and static pressure controls, consider using ultrasonic humidification, VAV reheat coils should not be used to provide primary heating to a space. Separate perimeter heat from ventilation for heating. Provide individual comfort control for each space including occupancy and CO2 control of T-‐stat & VAV where applicable. positively closing & robust 2-‐way control valves. Where possible VAVs should not be designed with reheat, but shall utilize their dampers to provide minimum flow as needed, based on space ventilation requirements and occupancy control. Eliminate “morning warm-‐up” mode at unit. Design AHU preheat and HHW for 140F max. at 5F OA design conditions and use reset schedule. For systems using VAV with reheat size the coils to use 95F RHW temp. Where possible the use of dedicated outside air delivery systems should be evaluated and buildings should be kept at a slightly positive pressure. Unoccupied set-‐points pertain to space temperatures only and are seasonal and location specific.


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Roof-‐Top and Self Contained Units: SEER > 21, Furnace >95% efficient, enthalpy wheel or other energy recovery, VFD, reset temp., etc. similar to AHU controls.

Air Cooled Split Systems: Air cooled split systems are generally not recommended for use. In cases where supplemental cooling is required all efforts should be taken to utilize chilled water. Where dx equipment is the last resort, utilize only high efficiency dx equipment.

Chillers and Cooling Towers: Use only chillers and towers with efficiencies in the top 5% across all load ranges, seasonally and as a system. Evaluate utilizing heat from the condenser water for preheat use and consider closed loop towers that save water and minimize the effect of contaminants and corrosion on heat exchange surfaces. Design for variable flows and temperatures to optimize performance and system efficiencies.

Water Source Heat Pumps: Use these to move heat from one system or area to use it in another. COP>2.5. The use of air cooled split units or heat pumps are typically not desired. Heat pumps or high efficient chillers that produce both chilled water and useable hot water are encouraged as we move away from steam and toward hot water central loops. See also section on Ground Source Heat Pumps.

Process Cooling Water Loop: Recover heat and reuse prior to heat rejection. Use variable flow and cascade heat recovery prior to necessary heat rejection. Note drawing 2, below, with minimized pumping and controls. The system relies on proper flow control and solenoid valves at each piece of process equipment. Use process cooling water Loops to eliminate the need for air cooled dx equipment and once through domestic water cooling. Extract usable heat from these process cooling loops to pre-‐heat DHW make-‐up or RHW returns. See drawing 2 below for typical heat recovery/rejection portion of the system.


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Drawing 2

Storm Water: All rain water run-‐off from impervious surfaces should pass through mitigation elements. Consider rain gardens, vegetative swales, vegetative roofs, permeable pavement, and collection and reuse for irrigation or gray water systems. Baltimore Rainwater tax: $48 per 800 square feet of impervious surface.

Domestic Water: Use only water efficient appliances in the top 5% of their class. Rest room sinks: 0.5 gpm with auto sensors, instantaneous water heaters at point of use. Toilets: 1-‐1.28 gpf, touch free automatic. Do not recommend dual flush flushometers. 0.8-‐1.0 gpf when tank toilet is used. Urinals: 1 pint per flush and touch free automatic or waterless in new construction with plastic drain pipe and cartridge-‐less type.

Elevators: Require Energy Star rated units, lights, fan and motor de-‐energized unless unit is in “call” mode.


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BMS/EMS: Simplify systems and controls to save first costs. Ensure individual comfort controls for individual spaces. The sequence of operations should be incorporated on the drawings along with corresponding schematics to provide easy interpretation. System information should be easily exported to real time trending, monitoring, fault detection or dashboard.. It is desired that alerts are created when equipment is over-‐ridden or exceeding energy parameters. Reduce the number of points to just what is needed for troubleshooting. Have capacity to trend all points for minimum of 72 hours. Incorporate occupancy control and CO2 sensing for AHUs where possible. Automatically turn lights and equipment off when no occupants are present.

Dashboards: Meter information should be pulled into a web accessed dashboard so results can be shared in real time.

Electrical Equipment and Systems

Electrical System: Correctly size transformer to ensure >30% loading. Upsize distribution wiring where appropriate. Include harmonics mitigation plan. Peer review of EE design by power system optimization expert. Perform electrical audit and correct identified load and harmonics deficiencies one year after spaces have been occupied. Transformers: Use only energy efficient ones rated for digital/electronic loads with harmonic mitigation. Ensure they are phase balanced and loaded to minimum 30% of rated capacity off peak and 50-‐70% during occupied times. Measure loads once spaces are fitted out and spaces are occupied, but no later than 12 months after Substantial Completion. Correct or replace oversized transformers as needed. Since 2008 transformers must meet NEMA TP-‐1 standards for energy efficiency. The transformers must also meet the DOE’s CSL-‐3 energy efficiency standards and have harmonic mitigation features. Transformers must have full rated efficiency at 1/6 load. Specify transformers so they operate at 50% or higher load when the building is fully occupied and meet the intent of NEC. Remember, transformers are designed to be loaded to 110-‐120% for short durations (an hour or less) and work best in the 70-‐90% range. Bottom line, the more the EE designer knows about the electrical equipment and loads being served by the transformer the better job they can do designing for most efficient and reliable operation.

Electrical Distribution: Control or mitigate system harmonics.

Emergency Power: Use Natural Gas generators for all future installations with BACT to allow for optimizing their use beyond just power outages. Consider CHP units and fuel cells for this role when performing your LCCA. Consider energy efficiency when choosing equipment and components (crank case heaters, thermal recovery, electric conversion, etc.)


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Lighting: Employ day light into >75% of occupied spaces, use Sola-‐tube for interior spaces where possible. Consider Photo-‐Luminescent Exit Signs. Use only LED lighting and with efficacy > 100 lumens/watt. Use fixtures that deliver proper light levels efficiently to the work surface. Use the best qualities of light possible. Do not over illuminate spaces. Use dark sky compliant designs for interior and exterior lighting. Use lighting layouts with the lowest watts/square foot to meet work surface light levels. Provide photometric calcs for all spaces. Move day light to work spaces with enhanced window use and with effective use of light tubes or skylights (Solatubes preferred)

Lighting Controls: Provide a detailed sequence of operation and schematic on drawings for easy interpretation of installing contractor. Provide occupancy lighting control (100% of facility spaces) and step dimming (vacancy controls) in office, meeting, classroom and similar spaces. Automatically control artificial light output anywhere glazing, skylights or Sola-‐tubes exist. Automatically turn lights and equipment off when no occupants are present.

DOE recommended Lighting Power Density (watts/sf) targets (2012) and desired foot candle levels. Goal: to achieve 30% better than ASHRAE 90.1 2010 and IES 2012

w/sf F.C. base F.C. max F.C. Unocc

Office (off, 50%, 100%) 0.7 20 30 0

Conference/Meeting Room 0.8 20 35 0

Corridor 0.45 10 15 0**

Restroom 0.4 10 15 0

Mechanical Room 0.5 10 15 0.5*, ***

Stairwell 0.45 10 15 0*

Lobby 0.35 10 20 0**

Research labs (Labs 21) 1.4 50 75 0

Classroom/lecture hall 0.7 20 30 0

Dining 0.6 5 20 0

Auditorium 0.7 5 20 0

Parking/Garage 0.2 1 1.5 0.5*

Residence 0.6 20 30 0

Athletic spaces 1.0 25 65 0

Exterior Walkways 0.7/lf 1 5 1


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* Occ sensors on individual fixtures recommended. Total darkness not recommended for retrofits.

** Some night lighting may be allowed for a “welcoming” experience when approaching these areas.

*** Fail safe Occ sensors should be used for lighting around mechanical or electrical equipment.

Electric Hand Driers or Paper Towels? If electric hand driers are used, they must effectively dry hands in <10 seconds, be energy star rated and their noise must not be disruptive to adjacent spaces. Two products that have been acceptable are the Dyson Airblade and the Excel Xlerator.

Water Coolers: Require Energy Star rated units with demand controls on compressor, water bottle fill spout and cartridge filter. JHU “Take Back the Tap” initiative.

Office Equipment: Require Energy Star rated units with preset sleep and off modes.

Vending Machines: Require Energy Star rated units. Eliminate display lighting when possible or ensure LED, control with VendingMiser.

Refrigeration and Freezers: Require Energy Star rated units, directing heat to plenum. Specify water cooled when available for research and larger units.

Desk and Lap-‐top Computers: Require Energy Star rated units. Install 1e software, aggressive energy saving and print paper saving defaults.

Space Types

Data Centers and Server Rooms: Cool the equipment (that is producing heat)to the manufacturer’s specs. Set room to 78F. Recover and reuse the captured heat (requires water cooled equipment or loop). Use free cooling when outside temperature is below room set point. Use only the most efficient back-‐up power, UPS and inverter system options. Consider CHP/CCHP (Trigeneration) as base load and emergency power. Design for power use effectiveness less than 1.2 and meter energy at centers > 0.5MW. Ensure design choices to meet capacity, reliability and redundancy do not reduce operational energy efficiency.

Research Spaces: Follow guidelines in Labs 21 and High Performance Labs. Use occupancy controls for lights and air flow. Design research spaces for six air changes occupied and four when unoccupied and under negative pressure to the adjacent spaces. Monitoring for toxic compounds can allow as low as two air changes when unoccupied by controlling supply and exhaust air accordingly. Use only ultra-‐high


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efficiency or high performance fume hoods and chemical storage cabinets. Retrofit existing fume hoods with baffles and recertify to perform to today’s VAV High Performance standards. Eliminate General Exhaust in lab spaces and use VAV for both SA and Hood Exhaust. Annually, decommission, clearly label and close exhaust damper on lab hoods not in use. Purchase only high efficient ULT freezers and arrange equipment rooms similar to modern data center designs (pull heat away from the machines). Purchase research equipment that is also best in class for energy efficiency. General lighting at no more than 50 foot candles. Use task lighting as needed to meet 70 FC. Decouple ventilation from heating and cooling systems. Design lab space plug loads for average of 0.5-‐1.0 W/SF and lighting loads for 0.5 W/SF. Employ Dedicated OA Systems and Chilled beam techniques to minimize wasted energy. Electrical Closets, machine and mechanical rooms: Do not use heating units or air conditioning units (except in lab equipment spaces when recovering and reusing the BTUs). Use thermostatically controlled fans or dampers to remove the heat to an exhaust system where it can be recaptured and reused as needed. Alarm spaces for temperatures above 95F and below 40F as appropriate.

Tel/Data Closets: Understand the expected heat output. Do not use air conditioning units for rooms with only routers, switches and terminal blocks. Use open plenum or thermostatically controlled exhaust fans to remove heat as needed. These rooms should be designed to operate below 85F and can use adjacent space air as make-‐up to their exhaust fan.

Mobile Equipment: Purchase the most energy efficient options available. Use lowest emissions vehicles. Use most sustainable or renewable fuel type. Trash, Recycling and Compost: Ensure there are accommodations for trash, recycling and compostable bins anywhere waste is generated. Work with Operations to ensure areas will accommodate bin size and type changes in the future. Ensure primary compost collection in restrooms and areas where food is prepped, served or consumed. Require hauler to share weight data separately for trash, recycling and compost.

Renewable Energy

Solar PV: PPA model, but ensure space is preserved on roof for future system. Systems can be placed on roofs, ground, parking canopies and parking garage roofs.

Solar Thermal: PPA model. Ensure optimal roof space is preserved for future system. Size to preheat the chosen building system’s lowest thermal load.

Solar Thermal Hybrid: PPA model, but ensure space is preserved on roof for future system. Size to preheat and pre-‐cool the chosen system’s lowest thermal load.


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Urban Wind: For new construction evaluate roof mount options. Preserve ideal roof space for future installations.

Bio Fuels: When possible, consider alternatives to fossil fuels for vehicles and equipment.

References

International Green Construction Code, 2012: http://publicecodes.cyberregs.com/icod/igcc/2012/index.htm?bu=IC-‐P-‐2012-‐000023&bu2=IC-‐P-‐2012-‐000019

ANSI/ASHRAE/IES Standard 90.1, 2013:

https://www.ashrae.org/resources-‐-‐publications/bookstore/standard-‐90-‐1

International Energy Construction Code, 2012:

http://publicecodes.cyberregs.com/icod/iecc/2012/

ANSI/ASHRAE/USGBC/IES 189.1 2014:

http://publicecodes.cyberregs.com/icod/igcc/2012/icod_igcc_2012_ashrae189p1-‐2011_par001.htm

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