home energy audit report report kalmia.pdf6 ventilation and indoor air quality evaluation: the stove...
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HOME ENERGY AUDIT REPORT
Auditor: , Certified Building Analyst, Building Performance Institute (BPI)
BPI ID #: CAN08020 Date of Audit: 12-15-09 Phone: xxxxxxxx E-mail: xxxxxxxxxxxx
Homeowner’s name:
Project Address: Building information: xxxxxx is a 53-year-old, four-bedroom, 1-story home with two
basements and two attics. According to Boulder County Assessor, the home was built in 1957,
but it is believed that the western half of the home was added on some time later. The kitchen
was remodeled around 1999. A wood-burning stove was added in 1997.
Reason for visit: A home energy audit was requested to determine recommendations to
improve the winter comfort in the music room, entranceway, and guest room. Issues of
concern were the single-paned windows, and the uneven heating, particularly of the north side
of the home.
Observations, Measurements and Analysis:
Insulation:
RIM JOISTS> The boards that make up the perimeter of the floor area between levels
are called the rim joists. No rim joist area was observable, without further probing
violating the finish of ceilings or walls.
WESTERN ATTIC>
o South of hallway (open, vaulted area, 3’ high, at its peak – over the kitchen): 8”
of fiberglass batts = R-24; and 8” fiberglass batts on the ceiling of the attic, in
the rafters – the R-value of the upper insulation is rather negated by an open vent
to the outdoors at the top of the vault.
o North of hallway (triangular, tight section – over the guest room): 0”-20” of
chunk fiberglass – this R-value graduates from R-4 to R-60 with the higher R-
value toward the center of the house and the least at the northern edge.
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EASTERN ATTIC> The insulation job in this section is incomplete. There was an
addition of fiberglass batts on top of mineral wool, but this was only done in some
portions of the attic. The portions with flooring placed have only 4” of mineral wool
under it.
There were unused batts rolled up or stacked, sitting useless in the attic.
Batts exist in more visible sections, and not in the section over the music room, the eastern
section of Susan’s office, nor the client bathroom.
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o Portion without batts (35% of the attic): 4”of loose mineral wool = R-12
Over the music room.
o Portion with batts and wool (30% of the attic): 8” fiberglass batts, on top of 4”
mineral wool = R-36
Some daylight is coming through at the highlighted portion of this location. This is over the
western half of Susan’s office.
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o Over the master bedroom (35% of the attic): 8” fiberglass batts = R-24
o A can light was found in the attic floor with no insulation in the surrounding
area.
WALLS in western part of home>
o 2x4 walls: 3.5” fiberglass batts = R-11
BASEMENT FLOORS AND WALLS>
o Un-insulated, concrete walls and slab floor: R-.8 – R-1.1, depending on
thickness of concrete.
o Under the guest room, was an un-insulated crawlspace.
o One finished room was reported to have insulation behind the drywall.
EXTERNAL INSULATION> No external insulation was evident.
Analysis: The home is losing heat and more insulation would provide more
comfort and lessen the energy bills. In a finished home, such as this, insulation
levels were assessed only at the exterior walls, at electrical outlet openings in the
western portion. See recommendations at the end of this report.
o BASEMENT> This home has an issue with the lower part of its thermal
barrier. Below insulated walls are only concrete walls – which are poor
insulators – and earth, which stays at about 54 degrees year-round.
Without a thermal barrier between the main living space and the basements
(i.e. insulation on basement ceilings), the heating system will continue to try
to bring the earth below the home to the thermostat set temperature.
Having a furnace adjacent to the finished room in the basement probably
provides this room some heat.
o CRAWLSPACE> The area below the guest room, which is uncomfortably
cold in the winter, was not very accessible. The ground is likely sucking
heat from this room quite readily.
o ATTIC OVER GUEST ROOM> The triangular section to the north was
filled completely with fiberglass insulation as far as what was visible. It is
unknown as to whether or not the insulation reaches the far, northern,
extremely tight edges of the attic adequately. This is the portion of attic
over the guest room, which is an area of the home that is reported as cold in
the winter.
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o BATH FAN VENTS / CAN LIGHT> Rather than slowing down the transfer
of heat, metal vents and light casings that are not properly insulated,
conduct heat from the home in the winter and into the home in the summer.
This recessed light casing allows a compromise in the air barrier as well as the thermal
barrier between the home and the attic.
o WALLS> Gaps and compressions in the batt installation may exist in the
walls around the edges and around plumbing and wiring. This is very
commonly seen in older homes with batt insulation.
Blower Door Test results and Air Sealing:
For this test, all windows and doors were closed, and no exhaust fans were on. The
home was depressurized to –50 Pascals of air pressure with reference to the outdoors,
by a RetroTec blower door. The interior temperature was measured to be 68° and the
outside temperature was 40°. During the test, drafty areas were noted to be the older,
double-hung windows on the east side of the home, and the forced-air supply vent in
the music room. The bathroom fans were very leaky. The doors to the basement, the
recessed light fixture, and the hatches to the attics were moderately leaky.
Analysis: The shell of the home is leaky and needs air sealing, especially at the
forced-air supply vent in the music room, and the bathroom fans. The music
room vent had a huge draft during the blower door test, which indicates a
disconnection in the ductwork, and thus, a breach in the air barrier from the un-
insulated basement. Furthermore, a large leak will hinder the heating of this
room, which is the largest comfort complaint from the owner. The master
bathroom fan has a metal damper, yet it had a large draft. The double-hung
window in the waiting room is unable to close completely in its current condition.
See recommendations at the end of this report to tighten the air barrier.
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Ventilation and Indoor Air Quality Evaluation:
The stove was gas, and was not vented to the outdoors.
The wood stove appeared to be properly vented to the outdoors.
The dryer appeared to be electric and was reported to be properly vented to the outdoors.
A dryer vent exists in the attic that is reported to be abandoned. This vent compromises
the air and thermal barriers of the home.
The lint from this vent was dumped on the attic floor and is lining the ductwork.
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Both bathrooms in the eastern portion of the home were vented to the attic.
This is the vent from the client bathroom.
Undetermined vents above the master bedroom, near the stairs to the basement. There
appeared to be various rooflines that were expanded on over time, and this venting
presumably went to the outdoors at some time.
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The vent from the master bathroom, with metal damper.
There was a radon mitigation system in the basement that appeared to be working.
Analysis: Concerns for indoor air quality, in general, come from mold (from
moisture), radon and soil gases, carbon monoxide from gas-burning appliances,
leaks in gas lines, tobacco, and off-gassing of volatile organic compounds from
things such as carpets and glues used in particle board, as in cabinetry.
o Two of the bathroom vents in this home vent to the attic instead of the
outdoors. Bathrooms, especially where showering takes place, put water
vapor in the air. Vents are designed to remove this from the home.
Moisture, which is an indoor air contaminant (breeds mold), as well as an
enemy of the structure’s durability (wood rot), should therefore be
removed, not just from the living area, but the attic as well. Perhaps even
more concern, however, is these metal vents allow a compromise in the air
barrier as well as the thermal barrier between the home and the attic. See
recommendations under the categories: “AIR SEALING>,” “INDOOR
AIR QUALITY>,” and “THERMAL BARRIER: ATTIC> Eastern attic.”
o With the current leakiness of the building shell, no continuous, mechanical
ventilation is required.
Combustible Appliance Zone Inspection:
The hot water tank was in good condition.
Angle of flue ductwork appeared to be adequate.
The flue ductwork used a moderate amount of elbows.
The sharing of flue ductwork for the furnace and the hot water heater was in
compliance.
There were no signs of charring or flame rollout on either appliance.
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There were no signs of condensation in the vents -- no rusting of ductwork.
The heating/cooling ductwork was in the un-insulated basement.
Analysis: The heating/cooling appliances will work more efficiently the ductwork
is covered in insulating wrap. A duct blaster test could be done to determine the
leakiness of the ducts.
Recommended Measures of Energy Efficiency Improvements, in order of priority:
1. THERMAL BARRIER: ATTIC> Add more insulation in the attic to achieve the R-
38 level that is required by the Boulder County Building Division. This will increase
the comfort in the home. Consider blown cellulose insulation, on top of existing batts
or mineral wool, which will also improve air sealing. The following
recommendations of insulation amounts are based on achieving an R-value of R-38.
a. Eastern attic:
i. The average R-value of this attic is R-23.
1. 30% of the attic is nearly at the code level of R-38, with 8” batts
on top of mineral wool.
2. The area over the master bedroom does not have mineral wool,
and should get 4” of cellulose blown over the existing batts.
3. The remaining space is only covered with mineral wool. First,
spread out the fiberglass batts already sitting in the attic. For the
remaining areas, apply:
a. 5” of extruded polystyrene foam board below walking
surfaces in the areas needed for access or storage, and
b. 7” of blown cellulose in all other areas (with dams built
up to separate the accessible areas from the cellulose.)
This should be done in the area above the music room to
improve the comfort level in that room. There are walls
in the attic that would allow separate sections to be added
to without taking away storage space in the center of the
attic.
ii. The two bathroom fans should be vented to the outdoors, or, at least the
vents should be brought to a height above the level of insulation, so that
the vents can be properly insulated, wrapped with a paper-faced
fiberglass batt to prevent condensation from forming.
iii. If the dryer vent in the attic is, in fact, abandoned, cut it down to the
floor level and shove a reinforced piece of fiberglass batt into the top
portion of the duct. If it is to be used in the future, duct it to the outdoors
and wrap the duct with paper-faced, 4” fiberglass batting.
iv. Evaluate if foam board can be applied to the hatch door.
b. Western attic, northern section (guest room): Consider having an infrared
camera evaluation here to determine how much the insulation could be
improved in this ceiling, as this is a room of discomfort in the winter. By
Quick and easy projects, with good payback, are HIGHLIGHTED in yellow. Items recommended as high
priority are underlined.
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making 7-9 small holes in the ceiling of the guest room, cellulose insulation can
be blown in between the ceiling joists to ensure the tight attic spaces there are
fully insulated. Tightly packed cellulose would also offer much more of an air
barrier, as well, than whatever fiberglass was able to be placed in this section.
c. Western attic, southern section (kitchen): Add 4” of blown cellulose on the
fiberglass batting. Add a 5” extruded polystyrene foam board on the western
attic hatch door.
2. AIR SEALING>
a. Seal the supply duct in music room. This can be done by a weatherization
professional. Most likely the leak is a disconnection of the ductwork from the
short elbow piece that attaches to the floor vent, and may be accessible from the
finished room.
b. Repair or replace the double–hung window in the waiting room so it seals when
closed. Along with the other double-hung windows* with weights for ease of
opening, consider closing off those open slots along the frame with spray foam
(in the slots where the weights are.) Great Stuff is a recommended product that
can be purchased at building supply stores. This would involve disabling the
weighting mechanism, but will close off large sources of air leakage. Caulk
window frames. If some windows are never opened, consider caulking them
closed.
c. Install bathroom fans that have airtight dampers.
d. The abandoned dryer vent should be investigated to determine if is sealed off at
the lower end of it. Air seal the upper end of it.
e. Replace the recessed light fixture in the eastern attic with an “air-sealed”
model, and properly insulate around it with a sheet-metal shield under the
insulation. Better still, close off this hole in the ceiling and install a non-
recessed light fixture.
f. Weather-strip, with foam strips, both attic hatches.
g. Air seal the door at the top of staircase to the unfinished basement with
weather-stripping.
h. Air seal the doors between the finished basement room, and the unfinished
portions of the basement with weather-stripping.
i. Caulk or use expandable spray foam in all
i. exterior penetrations of the home, from gas lines, electrical conduits, etc.
ii. where walls and floors meet,
iii. and at window frames and external doorframes.
j. In addition to these measures of air sealing, the insulation recommendations
listed here using cellulose and spray foam will improve the air barrier of the
home.
3. THERMAL BARRIER: BASEMENTS> Improve the lower portion of the home’s
thermal envelope.
a. Install sprayed, closed-cell foam on the ceilings of all the unfinished, basement
spaces to a level of R-25. This can be achieved with 4” of sprayed Urethane or
7” of the low-density Urethane. A high priority would be the ceiling of the
crawlspace below the guest room.
* one in Susan’s office and in the laundry area
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b. Consider completing the thermal boundary of the finished basement room.
Adding foam board on the floor, if the flooring is ever redone, and insulating the
doors between the room and the other unfinished rooms, could achieve this.
4. INDOOR AIR QUALITY>
a. Have the gas range vented to the outdoors.
b. Assure that the dryer is vented to the outdoors.
c. Install bathroom fans that vent to the outdoors.
d. Install a carbon monoxide monitor near where occupants sleep.
e. If air-sealing work is done, re-test the infiltration rate with a blower door test to
ensure adequate ventilation (ASHRAE 62.2 standard requires 7.5 CFM (cubic
feet per minute of airflow) per occupant). For, as the air barrier of a house is
tightened, the factor of indoor air pollutants intensifies. Also, have a worst-case
depressurization draft test of the hot water heater and furnace to assure they
have good draft, or “draw” up the flue, for healthy, indoor air quality. The
possibility of the home depressurizing from exhaust fans, chimneys, and dryers,
and therefore back-drafting combustible-air appliances, increases as the
infiltration of outside air into the home is decreased.
5. THERMAL BARRIER: WALLS / RIM JOISTS> Achieve R-19 or better in the
walls. An examination of the walls with an infrared camera would provide further
information on the adequacy of the insulation coverage and quality of batt installation.
The R-value listed here of R-11 is likely underestimating the true amount of heat
resistance based on how often batts are poorly installed, and how difficult they are to
install properly.
a. Consider rigid extruded polystyrene foam on the outside of exterior walls if the
home exterior is ever redone.
b. Alternatively, blown cellulose insulation dense packed into walls will increase
the resistance of heat transfer (R-value) and decrease air infiltration.
c. If the rim joists in exterior walls are ever exposed in a future project, consider
assuring this area is well air sealed and insulated with spray foam to prevent air
and heat transfer through the floor cavity areas.
6. LIGHTING> Finish replacing incandescent light bulbs (which waste 80% of the
energy they consume on heat, rather than light) with compact fluorescent ones. This
is one of the easiest energy retrofit and gives the most return on investment.
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7. APPLIANCES>
a. Setting the refrigerator and freezer to moderate temperatures will be most
efficient.
b. Clean the dryer vent of lint build-up every 4-6 months. This improves the
appliance efficiency.
The vent pictured, from your attic, had a build-up of ½ inch.
c. When it is time to replace them, consider replacing appliances with EnergyStar
rated models.
8. HEATING>
a. Cover accessible, forced-air ductwork with insulating wrap.
b. Consider installing a 90% efficiency, sealed combustion furnace when it becomes
time to replace the furnace. c. Adjust the programmable thermostat to reflect any lifestyle changes and
occupant needs, if they change over time.
9. COOLING>
a. Cover accessible, forced-air ductwork with insulating wrap.
b. Consider installing a whole house fan for summer evening cooling. This would
be more efficient than air conditioning.
c. Consider installing an Energy Saver Switch on the air conditioning unit.
10. HOT WATER>
a. Insulating wrap should be added around the hot water tank to improve its
efficiency.
b. Setting the hot water heater to a moderate temperature is also recommended.
c. Use low-flow showerheads.
d. Minimize running the hot water anymore than necessary (while brushing teeth,
washing dishes, or extra long showers).
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General Information:
Cellulose insulation is made from recycled newspapers, mixed with a flame retardant. It is
very environmentally friendly and non-toxic.
In the event that the exterior siding was ever taken down, a layer of extruded polystyrene foam
board on the exterior walls would add an excellent thermal and air barrier, without any thermal
bridging that occurs in wall cavity framing members.
When insulating attics, the insulation should be deep enough where it lines up with the exterior
walls to adequately create a contiguous thermal boundary with the wall insulation.
Rim joists are often inadequately insulated, as they are mostly solid wood, leaving little room
for insulating materials. Because there is not an enclosed space at the interior of a rim joist, as
there is in a wall cavity, this is not a good application of fiberglass batts, which would be
ineffective with air accessing the batt.
If a combustible appliance has drafting issues, carbon monoxide could spill into the home, or
worse, flame rollout from the appliance could cause a house fire. Drafting spillage happens
when the air pressure surrounding the open-combustion, atmospheric-draft appliance is more
negative than the pressure in the vent.
The importance of air sealing.
Homes need to separate the outside, unconditioned air from the inside, conditioned
(cooled or heated) air. To do so, homes need to have a thermal boundary that is aligned
with an air barrier. For, insulation with air moving through it works about as well as
skiing with only a fleece jacket – the wind goes right through it.
Most fiberglass batts in older homes have not been properly installed, such that they do
not completely fill the cavity. With gaps or compressions of the batts, convection
moves air around in the cavity, reducing the effectiveness of the insulation.
Where insulation is used in a wall cavity, all six sides of the cavity should be air sealed.
Latex paint and drywall offer air barriers on the finished side of a wall cavity, but
caulking often completes the job on the other five sides of the cavity. Where wall
assemblies meet ceilings and floors should also be caulked for a good air barrier.
Because hot air rises, a home creates a stack effect, which forces air to infiltrate through
low cracks and holes, and exfiltrate out through upper leakage areas.