North Carolina Sustainable Energy Conference 2009

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North Carolina Sustainable Energy Conference --
2009

• Home Energy Efficient Retrofit
• Scott Suddreth Building Performance
  EngineeringJeff Tiller Appalachian State
  University/ BPE

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Energy Retrofit Issues Building Envelope

• Attic Ducts? Air leaks? Insulation quality/
  quantity?
• Crawl space Moisture? Ducts? Air leaks?
  Insulation quality/ quantity?
• Walls Insulation? Sealable air leaks?
• Garage to House Air leaks? HVAC systems?
• Other tricky air leaks
• HVAC Efficiency? Tune-up? Duct insulation?
  Safety/ performance? Programmable thermostat?
  Control setpoints?

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Energy Retrofit Issues Hot water, Lighting,
Appliances

• Hot water fix leaks, water heater wrap, quality
  low-flow showers, faucet aerators, Energy Star
  appliances (washer and dishwasher)
• Lighting linear and compact fluorescents,
  exterior efficient lighting with controls, LED on
  the way, occupancy controls
• Appliances identify potential high energy
  users, convert to Energy Star, eliminate
  excessive refrigeration/ freezer units
• Electronics control on-time, phantom loads,
  look at energy use

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Efficiency and the Attic -- Summer
140 deg
75 deg
102 deg
70 deg
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Infiltration Controls
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Envelope Energy Usage
Duct Leakage
Infiltration
Ducts
Energy used to heat and cool
Doors
Walls
Ceilings
Windows
Floors
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Where does it all go?
Residential Energy Efficiency
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Ventilation Systems

• Bathroom exhaust fan with
• 6 intake duct from a grille near a clean source
  of exterior air into central return of HVAC
  system.
• A heat recovery ventilator or enthalpy recovery
  ventilator that is installed properly.

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You gotta crawl!
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No telling what you will find
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Dropped Ceiling over Tub
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Above Showers
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Air Sealing Chimneys and Flues
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Dropped Soffits
Allows heat to conduct or radiate through
Cold!
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Attic-to-House Connections
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No BIG Holes!
Cover with sheet material and seal
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Put a Lid On It
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Sealing Attic Kneewalls
An attic kneewall has unconditioned attic space
on one side and conditioned space on the other
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Infiltration Controls Needed
Fails Code?
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Unsealed Penetrations
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New and Old Penetrations
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Airtight Ceiling Finish?
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Going after the top plates
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Attic Air Sealing Locations

• Holes over chases and dropped soffits
• Open areas over lowered ceilings or wherever
  attic air can enter the interior wall framing of
  the home
• Holes under attic knee walls
• Unsealed penetrations larger than 1/16 around
  electrical wiring, plumbing, ductwork, HVAC
  system supply registers and return grilles, and
  other features
• Unsealed seams larger than 1/16 around lighting
  boxes, exhaust fans, and other devices that
  penetrate the ceiling finish
• Attic hatches and stairs (must be weatherstripped)

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Attic Air Sealing Locations (cont.)

• All penetrations
• Seams between top plates and ceiling finish
• Recessed lighting fixtures (in homes with more
  than 4 ventilated fixtures that are not IC
  rated and air tight, the fixtures must be
  replaced with IC rated, airtight fixtures)
• Seams in the ceiling finish (such as between
  pieces of tongue-and-groove boards or ceiling
  tile)
• Flues (if they require a clearance from
  insulation and wood, a nonflammable material such
  as metal flashing must span across the clearance
  space. The flashing must be sealed to the flue
  with a sealant rated for high temperature
  applications and to the framing or ceiling finish
  with a durable sealant rated for attic
  application
• All other attic air leaks

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Install Attic Insulation

• 1. Install attic dam at hatch or stair height
  of insulation or of platform
• 2. Blocking at attic eaves (should be sealed in
  place)
• Cardboard or Thermo-ply
• Rigid insulation or other material that complies
  with local fire codes
• Insulation contained in plastic bags
• 3. Preserve clearances to heat-producing devices
• Flues for fireplaces and wood stoves (Rated
  insulation, such as rock wool, may be installed
  between the blocking and the flue.)
• Recessed lighting fixtures without IC ratings
• Transformers and other heat-producing devices

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Attic Insulation Requirements (cont.)

• 4. Knob-and-tube wiring must not be covered with
  insulation
• 5. Install attic rulers prior to blowing
  insulation
• 6. Insulation must be installed to provide a
  minimum of the quoted R-value
• 7. Durable insulation must be installed on attic
  hatches and stairs such that the insulation value
  will be maintained after frequent use
• 8. Install attic card at completion

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Attic Clearances Needed

• Knob and tube wiring
• Flues and chimneys
• Electrical devices
• Transformers
• Recessed lamps
• Lighting fixtures
• Exhaust fans (run duct to outside vent)

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Attic Insulation

• Where to insulate?

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Air Sealing Post Drywall

• Attic access hatches must seal tight

Residential Energy Efficiency
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Energy Guardian
Residential Energy Efficiency
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Seal Air Leaks Through Floor

• If water is present in the crawl space, the
  source of the moisture must be located and
  eliminated prior to any measure being installed.
• Ample make-up air for combustion appliances
  general condition of appliances
• 1. Install ventilation system (Measure 4)
• 2. Install ground cover
• Complete coverage of earth floor
• The ground cover must lap up piers and columns at
  least 2 inches and be sealed to the structural
  members with mastic or caulk.

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Seal Air Leaks Through Floor (cont.)

• 3. Air leaks to seal
• Chases that extend through the floor of the house
• Open framing, such as for stairs or enclosures
  for chimneys
• Penetrations larger than 1/16 around electrical
  wiring, plumbing, ductwork, HVAC system supply
  registers and return grilles, and other features
• Other seams larger than 1/16 that allows air to
  move between the interior and the crawl space or
  unconditioned basement
• Doors between the interior of the home and the
  crawl space or unconditioned basement (must be
  weatherstripped)
• Seams between old subfloor with diagonal lumber

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Vapor Barrier in the Crawl Space
Unsealed
Sealed
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Residential Energy Efficiency
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Thermal Bypass
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Under Bathtubs
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Crawl Space Air Sealing Checklist

• Open chases covered and sealed
• Duct runs
• Flues
• Plumbing and wiring
• Other
• Framing transitions blocked and sealed
• Divergent floor levels
• Open wall cavities
• Stairs into crawl space or unconditioned basement
• Other

• Penetrations sealed
• Plumbing waste lines
• Duct runs into chases or wall cavities
• Electrical and plumbing supply lines
• Other

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Residential Energy Efficiency
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Residential Energy Efficiency
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Residential Energy Efficiency
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Residential Energy Efficiency
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CLOSED CRAWLSPACE DESIGN AND CONSTRUCTION
Residential Energy Efficiency
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12 Home Field Study Site
N
111
105
109
103
101
107
110
108
104
106
102
100
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Summer RH Summary
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Seasonal Energy Use and Savings
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WWW.CRAWLSPACES.ORG
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Uninsulated Ducts
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Leaky Ducts
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More Leaky Ducts!
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Main return line falling off boot. Looks like a
good job for MASTIC!
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Seal with Durable Materials
Duct sealing mastic (use fiber-mesh for gaps over
¼) Apply with brush or glove on the
leaks Achieve complete coverage with adequate
thickness
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All duct connections must be sealed with mastic,
including connections to Plenums Y-joints
Boots
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Filter Anyone?
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Air Register Maintenance

• Vacuum registers and vents regularly, and dont
  let furniture and draperies block the air flow.
  Inexpensive plastic deflectors can direct air
  under tables and chairs.

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Door Sweeps and Weatherstripping

• Weatherstrip leaky doors
• Check door sweeps to make sure they touch the
  door threshold when closed.

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Combustion Awareness
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Avoid Un-vented Heaters
Residential Energy Efficiency
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Mold Growth
Residential Energy Efficiency
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Programmable Thermostat
Residential Energy Efficiency
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Energy Star Appliances
Residential Energy Efficiency
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Use the Energy Guide
Residential Energy Efficiency
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Beware of Phantom Loads

• Did you know that your stereo is having a party
  while youre asleep? Thats right, its running
  up your electricity bill even when its off. Its
  called a Phantom Load.

Residential Energy Efficiency
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Water Heater Blanket
Residential Energy Efficiency
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Turn it Down When Your Gone

• If youll be going on vacation, lower the
  thermostat to 55 degrees. This will save energy
  while preventing water pipes from freezing.
• Turn off water heater if advantageous

Residential Energy Efficiency
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Water Heater Timer
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Lower Water Heater Temperature

• Set the water heater temperature at 120 degrees
  about halfway between low and medium. This will
  help save energy and prevent scalding, while
  keeping unhealthy bacteria from growing.

Residential Energy Efficiency
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Hot Water Savings

• Take showers, not baths. A five-minute shower
  will use about 7.5 gallons of hot water, while
  filling a bathtub can use up to 20 gallons.
• Use Low Flow Heads

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Leaky Faucets

• Fix leaky faucets, especially if it's a hot water
  faucet. One drop per second can add up to 165
  gallons a month thats more than one person
  uses in two weeks.

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Refrigerator Tips

• Check door gaskets annually
• Keep the refrigerator full
• Check the temperature
• Main body 36 38 degree F
• Freezer 0 5 degree F
• Avoid putting hot foods in refrigerator
• Keep foods covered especially liquids

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Energy Smart Cooking

• Use lids on pots to reduce time
• Use a microwave oven instead of a conventional
  range or oven when possible.
• Consider using a pressure cooker
• Consider copper bottom pans
• Keep the burner pans shiny
• Defrost in the refrigerator
• Dont lay cover oven racks with tinfoil
• Only use self cleaning feature after use

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Laundry Tips

• Always do a full load of laundry
• Dont add wet items to a load that is already
  partially dried
• Dry two or more loads in a row
• Clean the filter after each use
• Use the sun to dry clothes when possible
• Use cold water for most washes
• Do full loads when you use clothes washers,
  dryers, and dishwashers.

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Miscellaneous Low Cost Opportunities

• Water
• Showerheads (1.5 gallons per minute, gpm)
• Sink aerators (0.5 gpm)
• Repair leaks

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LightingLow Cost Opportunities

• Clean fixtures and bulbs periodically
• Occupancy sensors
• Replace EXIT signs with LEDs
• Replace T-12 with T-8 lamps
• T8 lamps offer better performance, more
  selection, less heat, elimination of hum
• Replace incandescent lamps with CFL

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Blower Door Testing

• The ONLY test that evaluates the air-tightness
  of a home
• Provides a measurement of the actual
  infiltration rate so that one tested home can
  be compared to another
• Helps identify leak paths
• Can show pressure imbalance problems and locate
  duct leaks
• Needed to qualify a home for EnergyStartm

You dont know until you test!
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Duct Pressure Test

• The ONLY test that evaluates the air-tightness
  of HVAC systems
• Pressure test finds leaks and estimates air
  flow
• Needed to qualify a home for EnergyStartm

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Got Questions? Give Us a Call

• Scott Suddreth, M.A.
• Jeff Tiller, P.E.
• Building Performance Engineering
• 828-265-4888

Residential Energy Efficiency
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