shawna henderson_cmhc_retrofitconf_oct009

(Deep) Energy Retrofits by House Type

Inves7ng in Exis7ng Housing

Shawna Henderson, CEO Bfreehomes Design Ltd.

Energy Efficiency programs aim for a 20 to 30% reduc7on in space and water hea7ng needs. A deep energy reduc7on aims for 70 to 90%.

St. Margarets Bay, 1996



Lunenburg, 2002

Wallace River, 2007

New SINGLE FAMILY housing = about 110,000/year

13.2 million exis7ng homes in Canada Nova Sco7a: nearly 50% pre-‐1970

CMHC About Your House Series: Renovating for Energy Savings

http://www.cmhc-schl.gc.ca/en/co/renoho/reensa/index.cfm Free download

12 house types, 6 ci7es

Range of ages:

1922 to 2000

1. How does house type/age affect NZEEH?

2. How does climate affect NZEEH?

Approaching Net Zero Energy in Exis7ng Houses

•  The Twike: 2 person human-‐electric hybrid •  5kw electric motor, Top speed 55 mph •  4 -‐ 8 kWh/100km, equiv. to 300 -‐ 600 miles per gallon

House as a System

Lost Opportuni7es – Low Hanging Fruit House Yoga – Flexibility & Endurance

Op7mizing a System…

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If this, then…

If this, then…

If this, then…

Where you are

Where you’re going

12 house types, 6 ci7es

Range of ages:

1922 to 2000

1. How does house type/age affect NZEEH?

2. How does climate affect NZEEH?



Vancouver Calgary Toronto Montréal Halifax Whitehorse

Ceiling Main Walls ExposedFloors

BelowGradeWalls

Slab

Vancouver 10.6 (60) 7.0 (40) 7.0 (40) 7.0 (40) 1.8 (10)Calgary 14.4 (80) 10.6 (60) 10.6 (60) 7.0 (40) 1.8(10)Toronto 10.6 (60) 7.0 (40) 7.0 (40) 7.0 (40) 1.8 (10)Montreal 14.4 (80) 10.6 (60) 10.6 (60) 7.0 (40) 1.8 (10)Halifax 10.6 (60) 7.0 (40) 7.0 (40) 7.0 (40) 1.8 (10)Whitehorse 14.4 (80) 10.6 (60) 10.6 (60) 7.0 (40) 1.8 (10)


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

General informa7on –  footprint = 17 x 6 m (55 x 20 m) –  4/12 roof, no significant heel @ eave –  framed w/2x4 walls –  poured concrete basement –  single pane windows


Best Case Scenario: Vancouver Bungalow

Assump7ons

Diminishing returns on increased insula7on Crappy windows

Full-‐size, central hea7ng system

Business as usual

Residen7al uses account for nearly 20%

of overall energy consump7on in Canada

Data: Office of Energy Efficiency, NRCan

0

50

100

150

200

250

300

350

400

As Is Conven7onal DER with solar

Energy Use Comparison

Ligh7ng

Appliances

Water

Space

50% reduc7on

80% reduc7on

Meeting DHW load becomes becomes bigger challenge than space heating as envelope improves

Space 65%

Water 17%

Appliances 13%

Ligh7ng 5%

As Is

Space 57% Water

21%

Appliances 16%

Ligh7ng 6%

Conven3onal

Space 33%

Water 8%

Appliances 46%

Ligh7ng 13%

DER with Solar Thermal

Shift the relationships between purposes and energy use

2 Halifax ‘Gut Rehabs’

ecoENERGY: 5, 15 ecoENERGY upgrade: ±60 Deep Energy Retrofit: ±80

Drop space hea7ng load by ± 50%

Drop space hea7ng load by ± 70%

Envelope first, then mechanicals

1375/79 and next doorAS IS

35'-

0"

10'-

0"

9"

10'-

0"

9"

8' -

0"

1375/79 and next doorFLAT ROOF W/FRONT GABLES RAISED

NOTE: bay area squared

off at 3rd storey FLAT ROOF OPTION OPTIMIZES SPACE @ 3RD FLOOR

roofline studies for developed upper floor

Insula7on: R21/3.5” soy-‐based polyurethane in original wall cavity R15/4” blown cellulose in new cross-‐strapped cavity

#1: get rid of water problems

A: No direct contact w/concrete or masonry walls or floors for moisture sensi7ve materials B: Moisture tolerant materials are not in contact with materials that will absorb water if there is problem C: Air7ght construc7on on founda7on walls and floors warms first condensing surface, mi7ga7ng moisture issues in living space

Plumbing and electrical services run in front of 2 lb foam insula7on and behind standoff wall – full depth insula7on throughout basement and header area

Spray-‐on Foam

Insula7on Blown-‐in Fibrous

Drainage Plane

Illustra7on from www.buildingscience.com

Think pool liner

5-‐ year payback based on $ spent vs. energy savings not the whole story – but how to quan7fy comfort?

Windows, siding = ‘permanent’ components w/20 yr planning horizon

Inside glass temp also impacts condensa7on and moisture issues in a house as envelope is improved. Mechanical ven7la7on required – low space hea7ng loads: can we use ven7la7on system to distribute heat?

From this …

… to this (reasonable facsimile of system)

97% efficient, 50k Btu natural gas condensing boiler augmen7ng solar thermal system DHW and space hea7ng delivered via dual-‐coil, 120 gallon storage tank

Two of each: 60% efficient, 120k Btu oil boiler 80 gal. electric water heaters + indirect tank, uninsulated in uncondi7oned space

Solar Thermal Combi System

From cast iron rads to infloor radiant on 12 and

16 inch centres

From high-‐temp hydronic baseboards to low-‐temp rads

Energy Reduc7ons

51000kWh – 18000 kWh

70% reduc7on in space hea7ng + 90% of domes7c hot water supplied Hea7ng Load: 160k – 80k – 50k Btu Energy Use: ??!! – 152mil– 60 mil Btu

House as an Investment Define investment period

What’s in your pocket at the end?

Alterna7ves … Scenarios for house Scenarios for money

Resale-‐ability? Non-‐energy benefits? Investment horsepower?

72” screen?

Maybe we need glasses?!

Two wall ovens + microwave? How many cooks?!

22 c.f. and up fridges? Whose army are we feeding?!?!

What’s the payback?

Phases Dramproofing & Insula7on 1

Residing/Reroofing & Insula7on 2 Replace Hea7ng System

Address ven7la7on requirements Adjust exis7ng hea7ng equipment if possible

Rough-‐in Solar Thermal System Install Drainwater Recovery

High-‐efficiency, small capacity unit backing up solar thermal system w/low-‐temperature hydronics

Investment/Energy Costs Oil $8,100 Electricity $7,300 Nat Gas $4,000

Conven7onal: $22k

Deep Energy Retrofit: $37k

DER w/solar combi: $52k

Oil $5,100 Electricity $4,600 Nat Gas $2,600

Oil $2,100 Electricity $1,900 Nat Gas $1,000

DER = 1.85x up front costs of Conven7onal

Conven7onal = 1.7x projected costs of DER

How to Frame the Analysis of Return on Investment for Energy Savings Measures Among the prac7cal range of investment decisions:

Which provides the largest “return”?

Which are in your budget range? Which achieves the desired returns within your investment 7meframe? What non-‐energy benefits are driving your decision? e.g., comfort and aesthe7c benefits, health and safety, greater control over energy use, ease of selling home, enhanced pride and pres7ge, environmental responsibility