Michael Clarke Monday, March 10th, 2014.

Instructor: Ian Kilborn

ESET 430 - Lab Assignment 6-7

Herchmer Crescent Residential Energy Audit

Description of the House

The house on Herchmer Crescent is a split-level, 2 story property. The front of the house (road side) faces East,

with the North wall oriented at -9° N. The size of the living area (1st and 2nd floors only) is approximately 1,200

ft2 (1,186 ft2). The volume of the entire heated building envelop is approximately 16,000 ft3 (16,134 ft3). This

volume includes the basement, crawlspace, 1st and 2nd floors, but not the attics (which are unheated).

Space heating is provided by a 20kW electric furnace. Water heating is provided by a 40 gallon electric hot water

tank. Additionally, a small natural gas fireplace gets used occasionally, and is mostly a decorative appliance.

Below-grade foundation walls consist of 10" concrete block. Within the crawlspace, the block is bare with no

insulation. Within the basement, the block is covered from the inside by a thin softwood facing with a small air

gap between the two. Also to note is that the joist header space within the crawlspace is only insulated on the

West facing wall with 2" XPS foam; the North and East facing joist header spaces are un-insulated.

First floor (above crawlspace) walls are framed by 2"x4" studs @ 16"o.c., giving 3.5" of space insulated with

yellow fiberglass insulation (R=3.5/"). These walls also consist of a 0.5" layer of gypsum board, a small air cavity

(R=1), OSB sheathing (0.5") and an outside brick veneer facing (4" thick). Second floor (above basement) walls

are similar in construction, with the exception of thin aluminum siding instead of brick veneer.

The roof is of a split-level gable construction, with the attic spaces unheated. The first floor attic/ceiling is

insulated with 5" of yellow fiberglass between studs 20" o.c. The second floor attic/ceiling is insulated with both

5" yellow and 7" pink fiberglass, also between studs 20" o.c.

There are two wooden doors, at front entrance (1st floor, brick veneer wall) and read entrance (basement, un-

insulated concrete block wall). There are also many types of windows on East/West walls, including vinyl double

pane sliders, a vinyl sliding door, a wood double pane fixed and a low-e vinyl double pane slider.

Air Leakage

To determine the leavel of air leakage at the home, a blower door test was done yeilding the following Values:

To give some understanding as to what these numbers represent, consider the following:

The very best new home will have an ACH50 of around 1.0; typical newer homes will have an ACH50 of about

4.0; mildly leaky homes will have an ACH50 value of around 7.0, and if an ACH50 value of 10-15+ is measured,

that would be considered a space will considerable air leakage issues.

Since the value measured for this home was 7.09 ACH50, it can be considered mildly leaky.

Also to note is the equivalent leakage area of 180.1 in2. This means that if all the areas of infiltration were added

up to form a single hole, it would have an area of 180.1 in2, slightly larger than 1 square foot.

A noticeable draft was present around the door to the basement, which would indicate high airflow from the

basement to the main floors. It's probable that substantial air leakage was emanating from the un-insulated

foundation walls in both the basement (behind the wood paneling) and the crawlspace.

Pie Charts (Heat Loss as $; Energy $ spent)

Introduction to Recommendations

The objective of this audit was to offer the home-owner recommendations that would yield the greatest savings

per dollar invested. To achieve this, we first had to model the building in RetScreen. We could then identify

those areas of the home which were the greatest contributors to heat loss and energy consumption. This data is

displayed visually through pie charts on the previous page. Finally, we could offer recommendations to alleviate

those losses and provide a dollar estimate of expected savings per year.

Recommended Upgrades

1. Natural Gas Furnace

Space heating through electricity is extremely expensive. The existing electric furnace

may be very efficient, but the operating cost over a cold Canadian winter is

extremely high. More than half the yearly energy dollars spent at the house are

through the existing electric furnace, totaling nearly $2700. Replacing the electric

furnace with a high efficiency natural gas furnace would result in substantial yearly

savings.

Replacing the existing 20kW furnace with a 70,000 BTU, 95% efficiency furnace

would yield as estimate $712 in yearly fuel cost savings. The payback for this upgrade

should be no more than 2 years, making it a very attractive option.

2. Reducing Air Leakage/Heat Loss in Basement/Crawlspace

Significant air leakage was noted coming from the basement during our blower

door test. This is most likely caused by the un-insulated concrete block walls in the

crawlspace, the inadequately insulated below grade walls in the basement and the

three un-insulated crawlspace joist header spaces. The best option may be to add a

2" layer of XPS foam to the crawlspace walls, fill the air cavity in the below grade

basement walls with spray foam and add 3" of fiberglass insulation to the un-

insulated joist header spaces. This would reduce the amount of air leakage from

these spaces, plus add additional heat loss protection.

After implementing these upgrades with the software model, expected yearly

energy savings were found to be $194. This is a moderate savings, but the upgrades

would not be difficult, nor too expensive to implement, so the payback time would

be reasonable: within 5 years.

3. Electrical Baseloads

Electrical baseloads are all loads within the house that consume electricity. This

includes appliances, electronics, lighting and more. Additional "vampire" loads

exist in the form of electronic appliances on standby, such as computers, stereos

and televisions. Currently, nearly $1300 a year is being spent to service these

loads, which total nearly 25 kWh's per day. If that 25 kWh's could be cut in half,

substantial energy savings could be accrued.

To achieve this, a swath of energy efficient upgrades would have to be initiated.

Replacing all incandescent lights with CFL's would be the first step. It may be cost

effective to replace older appliances like the washing machine, dryer, dishwasher

or refrigerator. Many provincial rebates exist to encourage homeowners to do

this. Turning off home electronics would reducing their idle electricity

consumption. Even remembering to turn off lights in rooms not in use would go

towards achieving energy savings.

If it would be possible to cut in half the current baseload electricity consumption of 25 kWh's, a yearly savings of

$307 would result.

4. First Floor Attic Insulation Upgrade

Attics are a substantial source for heat loss and air leakage if improperly insulated. The first floor attic is only

insulated with 5" fiberglass, which isn't sufficient. An addition 7" of fiberglass insulation would add almost 25 R

value, yielding an annual savings of $119. This would be a very easy and cost effective upgrade, with very short

payback time.

Other Potential Upgrades

Reduce the heating setpoint by 1-2°.

Increase the cooling setpoint by 1-2°.

Reduce the temperature of the hot water tank from 60°C to 50°C.

Upgrade one/several/all the house windows to low-e argon.

Install a heat recovery ventilator.

Appendix A: Volume Calculations

Space Measurements

Crawlspace 23' x 25'5.5" x 4'2" = 2439.8 ft3

Basement 20'3" x 26' x 8' = 4212.0 ft3

1st Floor 23' x 25'5.5" x 8' = 4684.3 ft3

2nd Floor 28' x 21'5" x 8' = 4797.3 ft3

Total Volume = 16,133.4 ft3

Appendix B: Weather Reconciliation Calculations

Appendix C: 3D Surface Charts of Electricity Consumption 2013

Appendix D: Daily Gas Consumption

42 Herchmer Gas Consumption - Actual

Days from Current m3

Date

last Reading since last

15-Jan-14 Actual 306 2,855.00 25.00

15-Mar-13 Actual 58 2,830.00 3.00

16-Jan-13 Actual 62 2,827.00 52.00

15-Nov-12 Actual 59 2,775.00 47.00

17-Sep-12 Actual 62 2,728.00 50.00

17-Jul-12 Actual 62 2,678.00 53.00

16-May-12 Actual 62 2,625.00 51.00

15-Mar-12 Actual 58 2,574.00 49.00

17-Jan-12 Actual 61 2,525.00 50.00

17-Nov-11 Actual 63 2,475.00 50.00

15-Sep-11 Actual 62 2,425.00 50.00

15-Jul-11 Actual

2,375.00

Total Number of days were gas was used: Sum(C4:C14) Total gas used (m3): Sum(E4:E14)

915

480.00

Average Daily Gas Consumption = Total gas used (m3) / Total number of days

"= 480 / 915"

0.525 Cubic Meters gas per day

0.000

0.100

0.200

0.300

0.400

0.500

0.600

0.700

0.800

0.900

Gas

co

ncu

mp

tio

n p

er d

ay (

m3

/day

)

Date

Gas Consumption (m3/day) over time