Deep energy retrofits aim to reduce energy use by 50-90% compared to standard retrofits which aim for 20-30% reductions. A deep retrofit may involve upgrading insulation levels in walls, attics, basements, and installing more efficient windows and doors. High performance retrofits are challenging due to the need for qualified contractors and financing options. Meeting hot water needs can be a bigger challenge than space heating for highly efficient homes. Location and house type can impact the feasibility of achieving net-zero energy use.

1. Deep Energy Retrofits
Energy Efficiency programs aim for a 20 to 30%
" water heating needs."
reduction in space and
A deep energy reduction aims for 50 to 90%."
Shawna Henderson, CEO"
Bfreehomes Design Ltd."

2. Approaching Net Zero Energy
in Existing Houses"
12 house types, 6 cities"
Range of ages:"
1922 to 2000"
1. "How does house type/
age affect NZEEH?"
2. "How does climate affect
NZEEH?"

3. 13.2 million existing homes in Canada,
approx 98% of overall housing stock"
"
Nova Scotia: nearly 50% pre-1970"
Halifax: dwindling land resources in city,
increasing sale prices"
"
Situation!
Higher energy prices, older houses:
OPPORTUNITY TO GO DEEP"
Challenge"
Qualified trades, Financing"

4. Don’t be tempted by the
low hanging fruit!"
"
House Yoga – Flexibility & Endurance"
"
Where is dew point?"
What is first condensing surface?"
Small extra cost vs. big energy savings?"
1” type 4 foam on 2x4 walls = Lost Opportunity
R10 or R12 + R5 = R15 to 17"
(vs. new code R24 min … what does resale look like in 5 years?)
"
3” foil-faced polyiso as ext air barrier:"
R10 or R12 + R18 = R28 to 30
"

5. Approaching
Net
Zero
Energy
in
Exis4ng
Houses
Upgraded
Envelope
Targets
(RSI/R)
Averages from superinsulated houses built/designed in the last 5 years
in Canada and northern US, incl. EQuilibrium House Initiative projects
Ceiling
Main Walls Exposed
Floors
Below
Grade
Walls
Slab
Vancouver
10.6 (60)
7.0 (40)
7.0 (40)
7.0 (40) 1.8 (10)
Calgary
Toronto
14.4 (80)
10.6 (60)
10.6 (60)
7.0 (40)
10.6 (60)
7.0 (40)
7.0 (40) 1.8(10)
7.0 (40) 1.8 (10)
Montreal
14.4 (80)
10.6 (60)
10.6 (60)
7.0 (40) 1.8 (10)
Halifax
Whitehorse
10.6 (60)
14.4 (80)
7.0 (40)
10.6 (60)
7.0 (40)
10.6 (60)
7.0 (40) 1.8 (10)
7.0 (40) 1.8 (10)

6. Assumptions we can challenge"
Canadian houses need full-size,
central heating systems"
The diminishing returns on insulation limit
thermal envelope improvements"
"
Windows have crappy performance"
Energy availability and low prices will remain
stable, so it’s business as usual"

7. Renovation Pyramid
"

8. The Envelope, Please!"
Focus on draftproofing, then insulation"
"foundation up"
Doors, windows replace/repair/retrofit"
"
Lower envelope requirements = "
Lower energy needs = "
smaller space conditioning requirements"

9. Ligh4ng
5%
Shift the relationships between
purposes and energy use"
"
As
Is
Appliances
13%
Water
17%
DER
with
Solar
Thermal
Space
65%
Ligh4ng
13%
Space
33%
Conven*onal
Ligh4ng
6%
Appliances
46%
Appliances
16%
Water
21%
Space
57%
Water
8%

10. Meeting DHW load becomes becomes
bigger challenge than space heating
as envelope improves"
Energy
Use
Comparison
400
350
300
250
50%
reduc4on
Ligh4ng
200
Appliances
Water
150
80%
reduc4on
Space
100
50
0
As
Is
Conven4onal
DER
with
solar

11. #1: get rid of water problems"

12. #2: don’t invite them back"
A: No direct contact w/concrete or
masonry walls or floors for moisture
sensitive materials"
B: Moisture tolerant materials are not
in contact with materials that will
absorb water if there is problem"
C: Airtight construction on foundation
walls and floors warms first
condensing surface, mitigating
moisture issues in living space"
Plumbing and electrical services run in front of 2 lb foam insulation and behind
standoff wall – full depth insulation throughout basement and header area"

13. Above-Grade Insulation
"
‘flash and batt’ interior strap-out or standoff
"
Min. 2” layer of 2lb foam for air barrier
"
!!! HEADER ALERT!!!
"
"

14. Biggest issue: DER with exterior insulation can
make wall more vulnerable to leaks and damage"
Especially at
attached shed
roofs "
Especially with
windows above"
Especially in
areas prone to
horizontal driving
rain"
Picture from BSI presentation at ACI New England 2010:
Windows: i.e., The Holes in Your Wall

15. OMG!!! BFFL!!!
The Whole House Drainage Plane
"

16. Outies Rule!"
Extended ½” ply window bucks flush with
3 to 4 inches of exterior foam"
Illustra4on
from
www.buildingscience.com
Another Bestie:"
Pan Flashings"
Innies:"
Window is in
same plane as original wall"
Pictures from BSI presentation at ACI New England 2010:
Windows: i.e., The Holes in Your Wall
• Simpler drainage plane connections and geometry"
• Lower cost (extra trim is interior material – we use drywall)"
• Similar appearance to original, tie in w/neighbourhood"
• Perhaps greater protection from wind-driven rain from inset"
• Some additional solar shading"
• Can use existing window trim"
• If windows are not going to be replaced, what choice?"

17. Comfort Envelope = Thermal Envelope
"
5- year payback based on $ spent vs. energy savings not the whole story
– how to quantify comfort?"
Windows, siding = ‘permanent’ components w/20 yr planning horizon"

18. Window Comfort 1
"
Inside glass temp affects rate at which occupants
radiate body heat to the glazing. "
It also impacts condensation and moisture issues in
a house as envelope is improved."
Mechanical ventilation required in DERs "
With low space heating loads: can we use ventilation
system to distribute heat a lá PassivHaus?"

19. Window Comfort 2
"
4 factors:"
Air Temperature"
Mean Radiant Temperature"
Relative Humidity"
Air Movement"
OK, 5:"
Proximity"
Where are you comfortable?"
…1’ …2’ …3’ …4’ from wall?"
Cuts down on useable room
size to stay comfortable – forget
issue with thick walls!"
Air Movement/"
Relative Humidity"
Mean Radiant Temp/"
Air Temperature"

20. Thermal/Comfort Envelope
"
Thermal Envelope shortcomings can be
fixed by improving equipment efficiency"
"
Comfort Envelope shortcomings leave
complaints, customer dissatisfaction and"
increased energy expense and pollution
because of higher thermostat settings."
"
Work with Thermal/Comfort Envelope."

21. Oh, ya, mechanicals…
"
Two of each:"
"
60% efficient,
120k Btu oil boiler"
"
80 gal. electric
water heaters +
indirect tank,
uninsulated in
unconditioned
space"
… to this"
(reasonable facsimile of system)
"
From this …
"
97% efficient, 50k Btu natural gas
condensing boiler augmenting solar
thermal system "
DHW and space heating delivered via
dual-coil, 120 gallon storage tank"

22. From monster cast iron rads
EVERYWHERE to infloor
radiant at 12 and 16 inch o/c"

23. From high-temp hydronic
baseboards EVERYWHERE to a
few wall-hung low-temp rads"

24. House as an Investment
"
Define investment period
"
What’s in your pocket at the
end?"
"
Alternatives …
"
Scenarios for house"
Scenarios for money"
Resale-ability?"
Non-energy benefits?"
Investment
horsepower?"

25. What makes us tick?"
Spending decisions NOT based on bottom line:"
– Comfort, safety, peace of mind"
– Personal goals"
– Ego gratification"
– Justification leads to cherry-picking"
– Community leadership"
DRIVERS ARE NON ENERGY BENEFITS"

26. Value of Non-Energy Benefits…"
…to utility
Transmission /distribution savings
Peak load restrictions
Reductions in arrears and late payments/write offs/bad debt
Reduced regulatory costs and discount payments
Reduced emergency service calls"
…to society
Economic impacts (job creation/tax revenue)
Improved housing stock/preservation
Emission/environmental impacts
Health and safety benefits
Water and wastewater savings"
"
What do all of these
benefits have in
common? "
They can be quantified.
"

27. How does the Homeowner/Ratepayer
Gain from Non-Energy Benefits?"
Financial"
Comfort"
Aesthetics"
Health and safety"
Noise reduction"
Education-related"
Convenience"
What do all of these
benefits have in
common? "
Except for #1, they are
difficult to quantify
objectively."

28. Broader, clearer financial analysis
"
Financial analysis does not begin and end with
payback on a product – Return on Investment (ROI)
is clearer indicator of how and where clients can
best spend their money"

29. EE Investment/Energy Costs
"
Conventional: $22k"
Oil "
"$8,100"
Electricity "$7,300"
Nat Gas "$4,000"
Oil "
"$5,100"
Electricity "$4,600"
Nat Gas "$2,600"
Deep Energy Retrofit: $37k"
DER w/solar combi: $52k"
Oil "
"$2,100"
Electricity "$1,900"
Nat Gas "$1,000"

30. How to Frame the Analysis of Return on
Investment for Energy Savings Measures
"
Among the practical range of investment decisions:"
"
"Which provides the largest “return”?"
"Which are in your budget range?"
"Which achieves the desired returns within investment timeframe?"
""
"What non-energy benefits are driving your decision?"
e.g., comfort and aesthetic benefits, health and safety, greater control over
energy use, ease of selling home, enhanced pride and prestige, environmental
responsibility"
"

31. Phases and Roadmaps
"
If this, then…
Where you’re going
If this, then…
Where you are
If this, then…

32. Building
Critical
Mass:
If this, then…
increased
demand
+
stable,
qualified work
force
"
If this, then…