EARTH ADVANTAGE HVAC REQUIREMENTS

Transcription

1 EARTH ADVANTAGE HVAC REQUIREMENTS Homes are performance tested by approved performance testing (PTCS) technicians to ensure systems and equipment work as designed. Technicians must follow the ENERGY STAR New Homes Performance Testing specifications. Complete specifications for equipment, installation, and testing can be found in the Technical Standards on the Northwest ENERGY STAR website or in the Performance Testing Field Guide. Training and Certification - Contractors working in the program must be trained and certified by the Oregon Department of Energy, or an approved program trainer, to seal and test ducts and perform combustion appliance zone (CAZ) testing. If a contractor will install heat pumps, additional heat pump commissioning training is required. Properly sized heating and cooling equipment Systems must be sized no more than 25% above a home s calculated heat loads using an industry approved heat load calculating method (e.g. Air Conditioning Contractors of America (ACCA) Manual J). Heat pump and air conditioning capacities should be rounded up to the nearest half ton, also based on an approved heat load calculating method. A copy of the heating calculation must be submitted to the verifier for all heat pumps and be available on request for combustion furnaces and boilers. Properly designed ducts Duct systems must be designed to deliver proper air flow to each room using an industry standard procedure, such as Manual D. Sealed combustion equipment All combustion equipment installed inside the conditioned area of the building must have a sealed source of combustion air ducted directly from the outside, known as sealed combustion or direct vent. This applies to furnaces, water heaters, fireplaces and all other combustion equipment, except for gas kitchen ranges. Equipment Efficiencies o Gas furnaces: AFUE of 90 or greater. o Heat Pumps: HSPF of 8.5 or greater. o Air conditioning unit: SEER of 13 or greater. All efficiency ratings must be confirmed at or Cover supply boots during construction All supply boots located in floors must be covered during construction to prevent debris from falling into the ducts. The cover should be solid, not a grate or screen. Seal around supply boots Gaps around supply boots allow air from the ducts to pass directly to the attic, wall or crawlspace. The gap around supply boots must be sealed. Most contractors use duct mastic to seal the boot to the

2 subfloor during rough-in. Caulk is a more appropriate sealant to use when the boot penetrates drywall. Temporary Filter at Return Grille A temporary filter must be installed in the return grille during construction if the furnace is used for dry out. (It is strongly recommended that the furnace not be used for drying out. Instead, electric furnaces or industrial dehumidifiers should be used). Duct Sealing and Testing Mastic paste is required on all duct seams and connections, including those on the air handler and heating unit. Tape is NOT allowed. The system is required to test at a maximum leakage less than 0.06CFM per square foot of floor area or 75CFM@50Pa, whichever is greater. The program provides a data collection sticker that should be filled out completely by the performance testing technician and applied to the air handler. If a system is difficult to access (i.e. attic or crawl space), the sticker may be attached to the electrical panel. Any gaps between duct boots and drywall or sub-floor should be sealed with mastic, caulk, or foam. Zonal Pressure Relief - Each room greater than 75ft 2 having a door and supply vent must have pressure relief. Return pathways shall be provided between axial zones (e.g. bedrooms, offices, media rooms, etc) and the main body of the dwelling. Return pathways include pass-through grilles, pressure-relief ducts, return ducts, or one-inch door undercuts. Return pathways should be sufficiently sized to limit pressurization of axial zones to 3Pa or less when the system is operating at maximum airflow. Heat Pump Commissioning (Cx) All split system heat pumps with ductwork must be commissioned through the BPA Performance Tested Comfort System (PTCS) protocol or by using the CheckMe! service. Installers must be trained and certified to provide this service. Commissioning report must be submitted to the verifier. Combustion Appliance Zone (CAZ) testing This is required whenever a vented combustion appliance used for primary space or water heating is present in a home. Depressurization of a combustion appliance zone by more than 3Pa with reference to outside is considered a potential health hazard and mitigation must be performed. If the combustion air intake source is not from the outside of the house, a CAZ test must be performed for that appliance. Fresh air ventilation If ventilation is provided through the heating system return, the performance testing technician should work with the builder and the Builder Outreach Specialist (BOS) to agree on the best ventilation strategy. Outside air should be delivered to the heating system return and have an electronic control. Clock timers are no longer allowed. Other strategies include

3 low noise exhaust fans, heat recovery ventilators (HRVs) or other options; contact your BOS to discuss other possibilities. Fresh air ventilation intake vents must be at least six feet away from any combustion appliance exhaust or pollution source. Important details: For indoor air quality reasons the air filter should be installed at the furnace downstream from the fresh air intake. That way any pollen or dust is filtered before it is sent into the home by the system. However, since ENERGY STAR homes have tight ducts, if there is no fresh air intake to the return the filters can be installed in returns in the living area for easy homeowner access. Heating systems installed in attics should allow enough space underneath the unit for R-38 insulation. Other considerations: Design the duct system to be inside the conditioned space to minimize leakage. Centrally located HVAC will allow for shorter duct runs and lower material costs. An envelope tightness test may be performed by either the verifier or the performance testing technician. Tested leakage in gas-heated or heat pump-heated homes must be 7.0 or less. Tested leakage of zonal electric, propane, and oil-heated homes must be 2.5 or less. These modifications are to qualify this house for the Earth Advantage Program. If you have questions contact your Earth Advantage Technical Specialist Earth Advantage, Inc. All rights reserved.

4 EARTH ADVANTAGE SPECFICATIONS FOR FRESH AIR VENTILATION Whole-House Ventilation Mechanical ventilation that complies with Oregon Residential Specialty Code section R303.1 (whole-house mechanical ventilation system capable of providing 15 cfm per occupant -- 2 occupants in first bedroom, 1 in subsequent bedrooms) is required. Operable windows shall not be used to meet mechanical ventilation requirements. A variety of options may be selected to satisfy the mechanical ventilation requirement for your project. The following describes the mechanical ventilation requirement, and a variety of options you can choose from to meet that requirement: Supply-only central air handler-integrated system Outdoor air is introduced into the cold air return side of the ducted HVAC system. An electronically controlled mechanical damper (closed when non-energized) must be used to control outdoor air flow to the cold air return. Outdoor air supply duct must be sized to provide a maximum airflow rate meeting Oregon code section R303.1 requirements during air handler operation. The electronic control system must prioritize outdoor air delivery to occur at times of normal heating and cooling run times. Fresh air supply must come from a location with good air quality. Locations to avoid include roof vents, driveways or high moisture areas. Exception Electronic controls are not required in conjunction with air handlers utilizing a blower with an Electronically Commutated Motor configured to circulate indoor air continuously at low speed when not serving a heating or cooling call from the thermostat, and the outdoor air supply duct is installed in one of the two following ways: An adjustable damper is provided on the outdoor air supply duct. Outdoor air supply duct must be sized to provide required ventilation at continuous low blower speed. The damper must be adjusted to limit airflow to specified ventilation levels at the blower high speed setting. A measurement of outdoor air flow at high blower speed must be taken to verify proper ventilation levels; or An electrically controlled mechanical damper (open when non-energized) is provided on the outdoor air supply duct. Outdoor air supply duct must be sized to provide required airflow rate at continuous low blower speed. During a heating or cooling cycle, the damper shall be energized to close to nearly shut (or fully closed if the damper plate includes a knockout orifice) during that cycle. Combined supply and exhaust system Introduction of outside air shall be accomplished as per Supply-only central air handlerintegrated system requirements, above, except the electronic control system may be replaced by a time clock that opens the outside air duct for ten minutes every hour without energizing the air handler blower and without regard for co-incident heating or

5 cooling cycling. A separate central exhaust fan sized and installed as per the requirements for Exhaust-only systems, below also is required. No inter-tie between the two system elements is required, however, both systems should run on timers set at similar schedules. Heat Recovery Ventilators (HRVs) or Energy Recovery Ventilators (ERVs) Manufacturer provided air flow balancing procedures must be followed. E/HRV shall not rely upon the main air handler blower unless the air handler has an ECM blower set to run at low speed during ventilation cycles except when heating or cooling is occurring. The use of flow balancing rings is recommended if ventilation unit does not have integral test ports as a standard feature. Exhaust-only systems (non-ducted heated homes only) Exhaust-only ventilation systems are allowed in homes not containing ducted heating systems. A continuously rated exhaust fan with a sone rating of 1.0 or less located in a central location providing an airflow rate meeting Oregon code section R303.1 requirements must be provided and must run continuously. Alternatively, programmable timer controls may be installed to operate ventilation system at run times that provide the specified ventilation rates of R Exception: the fan may be placed in the master bathroom if it is controlled to run continuously at a speed lower than its full rated airflow and activating the wall switch causes the fan to boost its flow to full speed to accomplish spot ventilation. Additional similarly controlled fans may be incorporated into the whole-house ventilation system, provided the combined flow of all the fans at low speed meets without exceeding the home s required ventilation rate. Other configurations meeting Oregon code section R303.1 may be applied. Please contact your Earth Advantage representative for approval of alternative systems. Spot Ventilation In addition to the whole house ventilation strategy, peak moisture loads such as cooking and showering must be addressed through spot ventilation. The provisions of Oregon Residential Specialty Code Chapter 15, Exhaust Systems, shall be followed, except that each bathroom containing bathing or spa facilities must be provided with an ENERGY STAR rated exhaust fan and a rated flow rate of no less than 80 CFM. A remote-mounted fan located at least four feet from the inlet grill shall be exempt from the sone rating requirement. These modifications are to qualify this house for the Earth Advantage program. If you have questions contact your Earth Advantage Technical Specialist at Earth Advantage, Inc. All rights reserved.

6 EARTH ADVANTAGE SPECFICATIONS FOR WINDOWS All windows must have a NFRC rating of U-.32 or better (a lower number). A double glazed vinyl frame window with low-e coating and argon gas fill is typical. This U-value information is available from window suppliers and appears on a sticker applied to each window. Window area is a key factor in overall energy use, affecting both heating and cooling costs. A heat loss rate of U-0.32 is equivalent to an R-value of 3. Compare that to a typical 6-inch wall at R-21 and windows lose heat seven times faster than walls. For this reason, Earth Advantage limits window area. The square footage of window rough opening cannot exceed 21 percent of the conditioned floor area. The limit is calculated by dividing the total rough opening area of all windows and glazed doors by the home s conditioned floor area. This window to floor area ratio must be.21 (21%) or lower. If a building site offers stunning views, it's not surprising that large windows would be desirable. Keep in mind that east or west glass can generate uncomfortable glare and excessive heat, which can render a room unbearable and drive up cooling costs. Please consider framing key focal points of a large viewscape with carefully positioned windows. Also, raise sill heights at least 18 inches above the floor. This reduces window area, without compromising views or reducing natural light. It also reduces glazing cost because tempered glass is not required. Consult your Earth Advantage representative for more ideas. If your design slightly exceeds the window limit, it may be possible to "trade-off" higher efficiency windows (lower U-value) for higher insulation levels in other building components (walls, floors and ceilings). Analyzing these trade offs can be done by the Earth Advantage representative for a fee. Tradeoffs must be calculated before construction begins, so contact your Earth Advantage representative immediately. These modifications are to qualify this house for the Earth Advantage program. If you have questions contact your Earth Advantage Technical Specialist at Earth Advantage, Inc. All rights reserved.

7 EARTH ADVANTAGE SPECFICATIONS FOR WATER HEATERS Either a high-efficient gas or electric water heater must be installed to meet Earth Advantage program specifications. Because a gas water heater will fuel the heating system it must also meet the below specifications. A gas water heater must meet the following energy efficiency ratings: below 60 gallons -.62 EF 60 gallons and above -.62 EF An electric water heater must meet the following energy efficiency ratings: 59 gallons and below -.93 EF 60 gallons or more -.92 EF A gas-fired tankless water heater must have an EF rating of.82. If you plan to install a high-volume water heater (for example, 75 gallons) contact Earth Advantage for options. Most large water heaters do not meet these requirements, so it s essential to learn about the available options. These modifications are to qualify this house for the Earth Advantage program. If you have questions contact your Earth Advantage Technical Specialist at Earth Advantage, Inc. All rights reserved.

8 EARTH ADVANTAGE SPECFICATIONS FOR APPLIANCES In order for this house to qualify for the Earth Advantage program a high efficiency dishwasher must be installed. High efficiency clothes washers and refrigerators are highly recommended. At minimum, appliances should be ENERGY STAR labeled. Additional points in Earth Advantage are granted for homes that achieve the more rigorous requirements of the Oregon Residential Energy Tax Credit. ENERGY STAR Appliances are listed at the ENERGY STAR website. ENERGY STAR standards for dishwashers were increased in Please be sure your model is on this list. A list of all qualifying appliances for the Oregon Residential Energy Tax Credit can be found at the Oregon Office of Energy s website. These modifications are to qualify this house for the Earth Advantage program. If you have questions contact your Earth Advantage Specialist at Earth Advantage, Inc. All rights reserved.

9 EARTH ADVANTAGE SPECFICATIONS FOR FRAMING TECHNIQUES The above job site will have intermediate framing features for the exterior walls on the upper level in order to qualify for the Earth Advantage program. The features below must be followed and will be inspected by a Earth Advantage Technical Specialist. Framing Features: Insulated headers Insulated corners, using sheet rock clips or California corners Full insulation behind partition wall intersections with exterior walls These modifications are to qualify this house for the Earth Advantage program. If you have questions contact your Earth Advantage Technical Specialist at Earth Advantage, Inc. All rights reserved. EARTH ADVANTAGE SPECIFICATIONS FOR AIR SEALING

10 One of the diagnostic tests performed on an Earth Advantage home is a blower door to test. This test measures the actual air leakage of the building in air changes per hour in the house after the shell has been completed. The specification for an Earth Advantage home is 7.0 ACH 50Pa (0.35 ACH natural) or less. To improve your chances of passing the performance test, try to accomplish as many of the following air sealing tasks as possible. Caulk all exterior wall bottom plates to the subfloor on the inside before drywall is installed. Caulk or foam any hole around pipes, wires, exhaust fans or HVAC ducting as it travels from heated to non-heated areas. Seal all rough openings around windows and doors with low expansion foam that will not affect the window frame. Use a rigid sheet material, such as OSB, sheet metal or rigid insulation to patch the large hole around tub and shower drains. Seal around the patch with expanding foam. Nail rigid sheet material, such as OSB, drywall or Thermo-Ply to the exterior walls and ceilings around fireplace enclosures, bath and shower units, pocket doors and soffits. Seal all recessed light fixtures by caulking between the fixture housing and the drywall. IC rated cans must be used in order ensure an airtight fixture. Install a rigid sheet material (drywall, OSB, Thermo-Ply) to the rafters before nailing tongue and groove wood ceilings. Install solid blocking between second floor joists where they cross the wall that separates the garage from the living space. Seal around the blocking with caulk or expanding foam.

11 EARTH ADVANTAGE SPECIFICATIONS FOR LIGHTING FIXTURES Seventy-five percent (75%) of all sockets OR fixtures must be filled with fluorescent lights. Energy Star labeled screw-in lights (spiral tubes) are required. Linear fluorescent fixtures must be T-8 or T-5 tubes with electronic ballasts. Good locations for linear fluorescents are kitchen cabinets, utility rooms, garages and indirect lighting applications. Compact fluorescent fixtures must be ENERGY STAR labeled. All fluorescent light fixtures must have electronic ballasts. Fixtures that experience high-use and where the bulbs are hard to reach are ideal for compact fluorescent lighting. Examples of some good locations are: Exterior porch and driveway lights Closets, garage, hallways Wall sconces T-8 or T-5 fixtures under cabinets. High efficient bathroom combination fan/fluorescent fixture UL / ICC rated fluorescent recessed lights All recessed lights in exterior (insulated) ceilings must be rated as air tight (ICAT). These modifications are to qualify this house for the Earth Advantage Program.