NEXUS: Buttoning Up Your Home for the Winter

The Green Roundtable
and

Buttoning up for the winter-
Basics of home energy
conservation

Green Roundtable

Consulting, education, training
and strategic planning

to create healthy environments by
integrating principles of
sustainability into mainstream
planning, design and construction.

Objectives
Discuss:

- Easy ways to reduce energy consumption in the home
(low-hanging fruit)

- Additional cost-effective measures (higher cost but
potentially big returns)

- Energy efficient lighting, appliances & equipment

- Improving performance of building envelope
(insulating & air sealing)

- Basic economics- incentives, payback time, etc.

Home energy use

Space heating represents about 50% of
the average home’s energy use

>90 percent of the embodied life-cycle
energy in the typical home is attributable to
operating energy (heating, cooling,
lighting, appliances, etc.)

(copyright © Green Roundtable 2007)

General approaches

- Make simple lifestyle adjustments

- Improve maintenance routines

- Make simple upgrades to fixtures in the home

- Upgrade appliances and equipment

- Make improvements to the building envelope

Building envelope, definition

All of the elements of a building that separate and
isolate the unconditioned, sometimes hostile
outdoor environment from the conditioned indoor
environment. This may include walls and wall
finishes, roofs and roof finishes, doors, windows,
skylights and basement floors and walls.


But first…
• Remove window A/C units in winter

• Close storm windows if you have them!

• Lock sashes; adjust closers on storm doors so that
the doors latch properly

• Install hooks on older (wooden) storm doors to make
sure weatherstripping makes tight seal

• Repair broken windowpanes; re-putty windows if
necessary

• The old familiar mantra: “Do you live in a barn?!…”
– Educate your children!

If you can‟t replace
broken window panes
right away, seal cracks
with a clear/ translucent
caulking material or
cellophane tape!


Low-hanging fruit- easy pickin‟s
• Lower thermostat by 1 or 2 degrees- 1 degree
lower for 8 hour period saves about 1% on heating
energy use (simple math: 2 deg for 24 hrs = 6%)

• Add humidity to the air; it makes a given temperature
feel warmer

• Lower your water heater to 120 deg. F, especially if
you have a newer dishwasher


• Close off a section of the house for the season if
practical (e.g. multi-zone heating); don‟t lower
thermostat below 55 deg.

• Close window shades if you have them…all the way to
window sills (interrupts convection loops)


• Drain a few quarts of water from your water heater
(at least 4 times per year). This improves efficiency
and extends tank life.

• Bleed radiators if valve is open & no heat


More low-hanging fruit…
• If it‟s too inconvenient to turn off your computer
between daytime use, at least turn it off overnight

• Regularly defrost refrigerators/ freezers

• Clean the coils on your refrigerator; clean door
gasket and mating surfaces

• Clean heat pump and air conditioner coils

• Use ceiling fans w/ cathedral or high ceilings to
eliminate temperature stratification (both heating and
cooling season)


More low-hanging fruit…
• Let bath water dissipate heat to room temperature
before letting water down drain- collect some of this
water for plants/ landscape/ toilet flushing.

• Do same for dish water- This also adds much-
needed humidity to winter air

• Wash your clothes in cold water; do full loads;
otherwise, don‟t use a higher water level or longer
cycle than necessary

• Use a „solar clothes dryer‟


Low cost, big return
• Insulate your hot water pipes (pipes closest to
water heater first)

• Add an insulation blanket to your hot water heater

• Install a low-flow shower head

• Install faucet aerators

• Fix leaky faucets, especially hot water

• Install a programmable thermostat

• Change your furnace filter (forced hot air systems)


Don‟t insulate top of
gas-fired water
heaters; leave access
panels & valves at
base clear as well


Don‟t waste too much
time trimming pipe
insulation to fit tightly
around elbows & valves;
wrap a few times with
wide (1 ½ - 2”) foam
self-adhesive
weatherstripping tape &
secure w/ electrical tape
if necessary


An example of a foam
weatherstripping tape
option for sealing pipe
insulation at elbows &
valves


Low cost, big return- continued
• Replace worn weatherstripping
• Use expanding foam insulation to plug obvious holes
in building envelope
• Add gaskets to electrical receptacle covers

• Control groupings of consumer electronics, like
entertainment centers from central power strip

• Install dimmer switches & occupancy sensors

• Buy Energy Star anything! (if it affects energy use)

• Use an auto shut-off electric kettle


Low cost, big return- continued
• Use CFLs!
-Don‟t mix w/ incandescent in enclosed fixtures
-Long payback time in little-used fixtures
-Use higher than incand. wattage-equivalent
(you‟re still saving over incandescent)
-Don‟t use in dimmed fixtures unless rated
“dimmable”
• See www.estarlights.com, www.efi.org
• Mercury in bulbs far less than mercury in stack gas
from power plant capacity needed to satisfy increased
demand from incandescent bulbs
• Must treat blown-out bulbs as hazardous waste

Improving the Building Envelope


Key Principle- Saving home energy

As a general rule, for the average home/
homeowner, the greatest energy savings will be
achieved through managing the demand side of
the equation, rather than the supply side.

In other words, you’ll get better bang for your buck
through energy conservation measures, like insulating
& minimizing air infiltration, than incorporating
expensive renewable energy systems such as wind
and solar.


Building envelope, functions
• Protect structural elements and interior of structure
from weather, esp. moisture

• Help to maintain proper thermal regime within
structure

• Help to maintain proper humidity regime within
structure

• Prevent infiltration of outside air and contaminants

• Acoustically isolate interior of structure from outside
noise

• In essence, act as „membrane‟ for the structure


Building envelope components
• Exterior finish- wood siding, vinyl siding, brick, etc.
• Weather membrane/ air barrier/ drainage plane-
building paper, Tyvek, Typar, etc.
• Exterior sheathing- usually plywood
• Wall/ ceiling cavities (inc. structural members &
insulation)
• Vapor retarders/ barriers
• Or monolithic masonry floors/ walls, with or without
insulation, exterior damp-proofing, etc.
• Interior wall finish


Preventing heat loss
• Insulate

• Air seal (prevent infiltration)

• Use landscape features- vegetative shields, etc.

• Address lifestyle issues

• Best bang for buck through air sealing! Begin here!


Air leakage pathways

Minimizing air infiltration
(sealing building envelope)

• Seal obvious openings- pipe penetrations, attic
scuttles, electrical receptacles, recessed lights, etc.

• Openings to attic spaces are some of worst offenders

• Any place where two building planes meet is good
candidate for air sealing

• For additions/ new construction, use exterior air
barrier to minimize infiltration


Housewrap to
minimize air
infiltration &
protect from
moisture


Air leakage proportion through various pathways


Attic hatches/ scuttles are a major leakage pathway


A commercial solution for attic openings

See also www.efi.org


A home-brew solution

Rim joist between floors:
A significant air-leakage &
heat loss pathway.
Expanding foam insulation
a good solution here


Seal joint between baseboards and
floors/ walls. Add molding if necessary
to conceal caulking.


Seal joints between intersecting planes w/ expanding foam


Electrical receptacles can be a
significant air leakage pathway.
Seal cover plates w/ foam gaskets.
Seal joint between electrical box &
wall with caulking, spackle or
drywall compound.


Some commercial alternatives
to gaskets/ sealing mentioned
previously.


Don‟t run insulation up to
and over canister
(recessed) light fixtures
unless they are “IC”
(Insulation Contact)- rated;
Otherwise maintain
minimum 3” clearance at
all sides


Fireplaces are usually NOT an effective heating appliance!
They lead to excessive heat loss via drafts up chimney, especially
when you have a roaring fire! Use glass doors & outside
combustion air source if practical. Close damper when not in use!

A sampling of window sealing/ insulating options
• Important note: Always provide at least one unsealed window
per bedroom & living level to allow fast escape in fire/ emergency
• Rope caulking to eliminate air leaks (provides no
insulating value) – can be re-used if carefully removed
• Shrink film w/ double-stick tape - one season use
• Plastic (or shrink) film w/ bead or spline track (“Tiger
track”); track can be painted to match woodwork – whole
system reusable from season to season if non-shrink
plastic sheeting used
• Rigid plastic (like Plexiglas™ sheet acrylic) with
weatherstripping & clips or magnetic tape – whole
system can be re-used from year to year – one of most
aesthetically pleasing options; magnetic tape option
allows easy escape

Air sealing, online product
sources
• www.efi.org

• www.conservationtechnology.com


Plexiglas retrofitted
to exterior of upper
sash; lower sash
gets retrofitted on
inside to assure
proper operation of
window


Interior storm window retrofit; made
from ceiling light diffuser panel;
provides additional privacy as well


Creative solutions:
Bubble-pack between
sash & storm window to
provide insulating value
(& additional privacy)


Windows
• Performance measured in “U-value”; inverse of R-
value; measure of material‟s ability to conduct heat;
the lower the U-value, the better

• Look for U-value of .35 or less

• Double-glazed, argon filled preferred; Diminishing
returns with triple glazing

• ‘Low-e’ coating reflects heat back into structure

• Always look for Energy Star & NFRC labels

• Typical heat loss through windows about 20%


NFRC Label


Seal gap between rough opening and
window sill/ jambs when installing new windows


Insulating guidelines
• Go for low-hanging fruit- e.g. add more attic
insulation first if it is accessible and is not well
insulated
• Button up your house to minimize cooling (A/C)
loads as well as heating loads
• Try to eliminate bridging heat loss through wall framing,
etc, as it greatly reduces overall insulation effectiveness,
e.g., cross-band attic insulation
• Don‟t forget the basement! It‟s often overlooked; heat
loss to ~50 deg. F ground surrounding uninsulated
foundation is assured according to the laws of physics!
• Look for additional opportunities to insulate (other
than typical wall/ ceiling cavity insulation)

Additional Insulating Opportunities

• Be creative!

• Examples:
- Behind built-in bookcases
- Behind cabinets
- Closet walls & ceilings

• Capitalize on opportunities to insulate, such as
when you have exposed exterior wall cavities during
remodeling projects


Bubble pack-
style radiant
insulation
stapled to back
of attic door


Ventilation
• It‟s generally difficult to make an old house too tight
(inadequate outdoor make-up air)
• Even in a tight house, a bathroom fan is often enough
to provide adequate ventilation; cycle on periodically w/
timer switch (and/or humidistat; see efi.org)
• Control internal sources of excessive moisture
• Provide dedicated (outside) combustion air sources for
large combustion appliances like furnaces & fireplaces
• Proper attic ventilation may extend life of roof and
help to eliminate ice dams
• Extremely tight houses may need heat-recovery or
multi-port supply (or exhaust) ventilation systems

Ductwork
• Move duct runs into conditioned spaces (thermal
envelope) if possible
• Seal ducts; use duct mastic for this if possible,
otherwise make sure duct tape is UL listed
• Insulate (& seal) ducts in unconditioned spaces; for
cooling (A/C) ductwork, make sure insulation has
external vapor barrier to minimize condensation on duct
surfaces
• Keep inside of ductwork clean
• When insulating ducts in unconditioned basement,
you may make basement too cold; may want to
insulate basement walls instead

Appliances
• Buy Energy Star!

• Upgrade refrigerator if more than 10 years old

• Buy horizontal-axis washing machines
-They save water and energy (and soap!)

• Buy dishwashers w/ booster heater

• Don‟t buy oversized air-conditioners


More energy conservation strategies
• Put radiant reflecting panels behind radiators
• Keep baseboard convectors clean
• Close all curtains and shades at night during winter
(can help to break convection loops even if loose-
fitting); install closed-top window cornices if you are
using curtains or drapes
• Keep gas appliances tuned, including stoves; look
for blue flame; see mfgr for adjusting burners
• Employ manufacturer-recommended maintenance
routines for heating & cooling equipment. This may
include adjusting burners, lubricating motors and
changing filters.


• Use microwave oven for cooking; in addition to
consuming less power for cooking, they may help to
reduce summer cooling loads

• Shade air conditioner and heat pump condensers w/
vegetation or artificial shading (be careful w/
deciduous vegetation)

• Remember that A/C units also dehumidify, so you
may feel comfortable at a higher temperature


• Use deciduous vegetation on south, SW and west
sides of structure for summer shading; use vines on
trellises too

• Install awnings, overhangs and other shading
structures, such as pergolas

• Use retrofit heat-reflecting window films on west-
facing windows (look for NFRC label); for new
windows, choose units w/ low solar heat gain
coefficient (SHGC) for west-facing walls


• Install white window shades to help keep house
cool in summer
• Make sure attic space is well vented
• Use whole-house fans to exhaust warm air from
house in summer; run mainly at night to flush w/ cool
air; close windows during very hot days
• Install radiant barriers on underside of roof rafters;
can help to warm in winter and cool in summer; don‟t
interrupt ventilation pathways
• Use double-wall cellular reflecting window shades
w/ edge guides or “Energy Track” or window quilts


Next steps- Home energy saving
• Use utility bills to establish energy use baseline
• Get energy audit/ assessment (MassSave.com;
Energystar.gov; Conservation Services Group:
csgrp.com)
• If your house is very leaky to begin with, don‟t start
with an energy audit- do air sealing and insulating
first
• Verify improvements w/ blower door testing,
thermograph, etc.
• Verify improvements through future utility bills-
establish new baseline
• Make additional improvements as budget permits

Blower door
test to
measure air
leakage


Thermograph to check heat loss through walls (insulation effectiveness)


Funding conservation & renewable
energy projects


Rebates and incentives
• Federal Energy Policy Act of 2005
• Energy efficient mortgages
• MA state sales tax exemption
• MA state renewable energy tax credit
• Mass Technology Collaborative‟s Commonwealth
Solar Initiative
• Utility incentives
• See DSIRE database (Database of State
Incentives for Renewables & Efficiency):
http://www.dsireusa.org/


Federal Energy Policy Act of 2005
Examples:
• Energy Star windows/ skylights: 10% of cost up to
$200 for all windows

• Exterior/ Storm doors: 10% of cost up to $500

• Insulation: 10% up to $500

• Geothermal heat pump: $300

• http://www.energy.gov/taxbreaks.htm

• Credits good only for upgrades performed
in 2006/ 2007


Energy Efficient Mortgages
• Allows you to increase your debt-to-income ratio
• Remodelers/ Refinancers:
-Owner gets all the EEM benefits without moving.
-Make improvements which will actually save
money.
-Increase the potential resale value .
• Home Energy Rating System (HERS) report must
indicate that home will save money as a result of the
improvements- http://www.energy.ca.gov/HERS/;
http://www.energyratings.org/
• For more info:
http://www.pueblo.gsa.gov/cic_text/housing/energy_mort
/energy-mortgage.htm

MA Renewables Tax Credit

• Personal tax credit
• Solar Water Heat, Solar Space Heat, Photovoltaics,
Wind
• 15% of cost up to $1000
• Excess credit may be carried forward three years
• http://www.state.ma.us/
doer/programs/renew/renew.htm#taxcred


MA State Sales Tax Exemption

• Solar Water Heat, Solar Space Heat, Photovoltaics,
Wind, Geothermal Heat Pumps

• 100% of sales tax exempt; no maximum

• http://www.state.ma.us/
doer/programs/renew/renew.htm#taxcred


MTC Small Renewables Initiative

• PV, wind, microhydro

• Rebates up to $50,000

• See http://www.masstech.org


MTC Commonwealth Solar

• $68 M Funding

•http://www.masstech.org/renewableenergy/commonw
ealth_solar/index.html


Typical utility rebates

•High-efficiency space heating equipment

•High-efficiency indirect water heating equipment

•ENERGY STAR® qualified windows

•ENERGY STAR® qualified thermostats

•ENERGY STAR® qualified central air conditioning

•ENERGY STAR® air source heat pump systems


Energy Star savings calculators

http://www.energystar.gov/index.cfm?c=dishwash.pr_dishwashe
rs
http://www.energystar.gov/index.cfm?c=clotheswash.pr_clothes
_
washers
http://www.energystar.gov/index.cfm?c=boilers.pr_boilers


Rating Systems/ Resources

• Energy Star Homes- www.energystar.gov

• HERS (http://www.energy.ca.gov/HERS)

• International Energy Conservation Code (IEEC)-
http://www.iccsafe.org/

• LEED - www.usgbc.org


Use NEXUS as your green resource!

• Upcoming workshops

• Reference library

• Samples library

• Cyber Lounge

• Online resources at nexusboston.com (in the
pipeline)

• Local green building community


Local Resources


THANK YOU
www.greenroundtable.org
info@greenroundtable.org
617-374-3740

The Green Roundtable, Inc. (GRT) is an independent non-profit
organization whose mission is to mainstream green building and
sustainable design and become obsolete. We work toward this goal
by promoting and supporting healthy and environmentally
integrated building projects through strategic outreach, education,
policy advocacy and technical assistance.

Located in downtown Boston, NEXUS
welcomes all to come ask questions,
research topics, and attend tours and
www.nexusboston.com events on green building and
38 Chauncy Street, Boston sustainable design innovation.

NEXUS: Buttoning Up Your Home for the Winter

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