Energy

Claudette Reichel  |  6/27/2008 1:31:45 AM

RESOURCE-EFFICIENT

Energy-Efficiency

ENERGY STAR Home

__  Certified ENERGY STAR Home

Design for the Climate

Landscaping for energy savings:

__  Deciduous trees shade W, SW, E and SE sides of house

__  Large shrubs or trellis with vines on W side

__  Ground cover, mulch near house to reduce reflected heat

__  Little unshaded pavement near house, none under windows

__  Evergreen shrubs and trees grouped as windbreak on N side

Overall house design:

__  Compact building layout to minimize total surface area

__  Open planning, min. corridor area (space-efficient design)

__  Kitchen, laundry rooms are not on W side

__  Living areas, kitchen have N or S windows

__  Porches, patios, etc. on N & S sides (unconditioned living space)

House design elements to minimize solar heat gain:

__  More wall area faces within 20° of due S and N

__  W facing glass <2% of floor area

__  E facing glass < 3% of floor area

__  2-ft. or larger overhangs

__  All W, E and S glass shaded

__  Garage/carport on W or E side of house (blocking sun)

__  No skylights (except light tubes)

__  Reflective roofing (min. 0.25 solar reflectance)

__  Light color brick or siding

Design elements for passive solar winter benefits:

__  S overhangs sized or louvered for summer shade and winter sun

__  Thermal mass flooring along S glass

__  S facing sunroom with mass floor, walls

House design elements for mild seasons:

__  Operable windows placed for cross ventilation

__  Porch open on three sides or in breezeway

Windows

__  ENERGY STAR or NFRC labeled windows, whole units rated at:

__  < 0.40 SHGC (solar heat gain coefficient)

__  < 0.30 AL; prefer 0.20 (air leakage)

__  < 0.65 U-factor in climate zone 2.; 0.40 in climate zone 3 (heat conduction)

__  > 0.50 VT (visible light transmittance)

__  Or, spectrally selective, southern climate low-e, insulated units

__  All W and E glass has 0.40 SHGC or shade screens

__  If passive solar, S facing glass is high solar gain low-e

__  For daylighting, 0.80 VT on N, and S if shaded

Tight Construction (Air Sealing)

Continuous air barrier surrounding conditioned space via:

__  Exterior air barrier

__  Airtight Drywall Approach interior air barrier

__  Sealed, airtight floor system

__  All hidden bypasses sealed from attic and crawl space air

__  Bottom plate of exterior walls sealed to foundation

__  Band joists between floors sealed

__  All penetrations in building envelope sealed

__  Airtight electrical boxes (or sealed by hand)

__  Low infiltration windows and doors

__  Fireplace: sealed from attic, outside air duct, tight damper, glass
     doors

__  Weatherstripped, insulated attic access (or in unconditioned area)

__   No recessed lights, or only ICAT used

__  Tight dampers, sealed housings on exhaust and inlet vents (exhaust
      not vented into attic)

Insulation Systems with Good “Whole-Wall” R-Values

__  Continuous insulation surrounding all conditioned space (except
      slab floor)

Recommended Insulation Material R-values:

__  Attic: R 30-38 in climate zone 2; 38-49 in zone 3

__  Cathedral ceiling: R 30-38 in zone 2. R 38 in zone 3.

__  Wood frame walls: R 13-19 in zone 2.; R 18-19 in zone 3

__  Concrete or masonry walls: R 13

__  Band joist: R 13-19

__  Floor over unconditioned space: R 13-19 in zone 2; R-19-25 in zone
      3

__  Steel frame: R 19-32 walls; R-49 attic, R-19-25 raised floor (must
       include exterior insulating sheathing)

Elements of Insulation System:

__  Insulation installed without gaps, voids and compressions

__  Radiant barrier under roof decking (if a/c ducts HVAC in attic and
      nonreflective roofing)

__  Building/insulation system with continuous coverage (thermal
      envelope)

__  Insulation type with extra advantages (see Ref. Guide)

__  Insulated window and door headers

__  Insulated corners and T-wall intersections

__  Insulated attic access door (R 19)

__  All insulated doors (R 5-15)

__  All glass low-e insulated; nonconductive framing

HVAC - Efficient Cooling and Heating

ENERGY STAR labeled cooling and heating equipment:

__  Air conditioner: > SEER 14 system

__  Gas furnace: > AFUE 0.90 (0.80 may suffice in climate zone 2)

__  Heat Pump (air source): > SEER 14, > HSPF 8.2

__  Geothermal heat pump (closed loop): EER 14.1, COP 3.3

__  Equipment is performance-tested

Alternatives with special advantages

__  Geothermal heat pump with water heating

__  Variable speed air conditioner or heat pump

__  Integrated gas space and water heating system

__  Manual J sizing (not oversized )

__  Sensible Heat Ratio < 0.70 SHR (min. 30% dehumidification)

__  Zoned heating/cooling (zone control system or multiple units)

__  Programmable thermostats

__  Outdoor thermostat on heat pump

__  Heat pump has gas back-up heat

__  Compressor on N or E side of house

Minimized duct losses:

Ducts and air handler (AH) within conditioned space (inside
      insulation “envelope”:

__  In sealed soffit or dropped ceiling, AH in closet

__  Or, in cathedralized (semiconditioned) attic

__  Or, in insulated, sealed enclosure above ceiling

__  Supply ducts, AH and all connections correctly sealed with code
      approved mastic

__  Duct insulation (R 8 if not in conditioned space)

__  Sealed return plenum or duct

__  Manual D duct and return design

__  Airflow measured and balanced with airflow hood

__  Central supply trunk (not octopus layout)

__  Duct runs and registers not extended to exterior walls

__  Air returns, transfer grilles or transoms for all BRs

__  Tested duct leakage < 5%

Other Efficient HVAC equipment (see Healthy/IAQ for Ventilation):

__  ENERGY STAR dehumidifier (if needed)

__  ENERGY STAR ceiling fans in often-used areas

__  ENERGY STAR quiet, outside exhaust fans (< 1.5 sones)

Appliances with Low Life-Cycle Cost

__  ENERGY STAR refrigerator, clothes washer, dishwasher

__  ENERGY STAR electronics

__  Efficient dryer, oven, etc. (compare EnergyGuide labels)

__  If well or pool is present, efficient pump

Efficient water-heating system options:

__  Integrated with geothermal heat pump

__  Heat recovery unit on air conditioner compressor

__  Solar water heater, certified

__  Heat pump water heater

__  Tankless gas water heater

__  >0.62 EF gas water heater

__  >0.92 EF electric water heater

__  Insulated hot-water pipes and tank

__  Central location of water heater

Lighting with Fewer Watts, Less Heat

__  High color, low wattage lighting throughout house

__  Fluorescent tubes, electronic ballast in attractive built-ins

__  EnergyStar fixtures

__  Compact fluorescents

__  LED fixtures

__  High-efficiency outdoor lighting

__  Photovoltaic lights

__  Outdoor fluorescents

__  High-pressure sodium or metal halide

__  Controlled, diffuse daylighting

__  0.8 VT N and shaded S glass

__  Light tubes

__  Light color scheme interiors

__  Motion or photo sensors

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