Deep Energy Retrofit (DER) Workshop January 12, 2013

Sustainable Living Resource CenterCottekill, NY

Thank you

Manna Jo Greene

Why DER is Needed …• Fuel sources, therefore fuel prices are volatile, provides “hedge”• Operating costs burden homeowners, money exits local economy • Current weatherization/Home performance strategies

– (insulation placed between studs, 15% reductions, incremental benefit) vs.

• Deep Energy Retrofit strategies – (install insulation to exterior, air seal, reduce mechanicals, 65 – 75%

reductions, provides step function boost benefit)

• Benefits to preserving entrained energy of existing stock

Age of Existing US Housing Stock

Source: American Housing Survey 2005

Almost 60 million housing units built before the first oil embargo in 1973

© Marc Rosenbaum - EnergySmiths

Candidates for DER … both built within the past 20 years

Credit: Tony Abate

Credit: Marilyn Kaplan

There are several strategies for implementing a DER; this Pilot focused on the exterior insulation strategy for the following advantages:•Allows continuous, un-bridged insulation layer

•Facilitates exterior air barrier installation

•Can be installed while the home is occupied

•Thickness of insulation is not limited by wall thickness

•Eliminates the problems caused by blocking, bracing and other internal framing elements causing missed (un-insulated) wall cavities

0

10

20

30

40

50

60

70

80

April

May

June Ju

ly

Augus

t

Septe

mbe

r

Octob

er

Novem

ber

Decem

ber

Janu

ary

Febru

ary

Mar

chApr

il

Av

era

ge

te

mp

era

ture

°F

, B

os

ton

MA

50.5F - Dewpoint of 70F, 50% RH

41.1F - Dewpoint of 70F, 35% RH

27.7F - Dewpoint of 70F, 20% RH

Condensation Potential

70F

20F

Temperature gradient across a wall

• Note that the temperature of the interior face of the sheathing is 20F – well below the dewpoint of the inside air.

• If air from the inside reaches the sheathing in any significant amount, condensation will occur.

• Air leakage through a small hole can move 100 times more water into a building cavity than is transported by vapor diffusion, so air barriers (AB) are more critical than vapor diffusion retarders (VDR)

• With 2 inches of polyiso at R-13 the interior face of the sheathing is 41F – little condensation risk.

70F

20F

© Marc Rosenbaum - EnergySmiths

2x6 cellulose 18% wood Nominal R21, Actual R = 15.8 77% of nominal R21

2x6 cellulose 18% wood 4” SPF Nominal R45, Actual R = 41.0 90% of nominal R45

Heat flow and R values in walls

Foam (SPF) placed ON the wall is a strategy that reduces thermal bridging.

Credit: Marc Rosenbaum (Energysmiths)

Major Renovation Invokes Building Permit … eliminates “kicking the can”

Air Infiltration Measurements

DRP1 DRP2 DRP 3_4 DRP 340

2

4

6

8

10

12

14

16

18

20

Change in Air Flow

ACH 50 Before ACH 50 DER Series3

Deep Energy Retrofit Houses

ACH

50

from

CFM

Mea

s.

ACH after DER

ACH before DER

Average Total MMBTU / Unit (4 Utica Houses)

Oct-09

Oct-10

Oct-11

Nov-09

Nov-10

Nov-11

Dec-09

Dec-10

Dec-11

Jan-10Jan-11

Jan-12Feb-10

Feb-11

Feb-12

Mar-10

Mar-11

Mar-12

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

3.8 2.41.9

8.7

3.5 3.8

13.6

7.6

5.9

26.1

10.89.3

24.9

11.110.0

20.6

10.27.3

Series2 Series1Fall - Winter Months

'09 - '10 Before, '10 - '11, '11- '12 DER

MM

Btu

Phase II … PON 2254, Exploratory Envelopes

• Develop repeatable strategies that scale• Achieve following technical objectives:

– Whole house assembly, R > 25– Total air leakage, < 0.25 CFM50 / ssf– Labor & material / ssf = $10

• Combine strategies to optimize influence • Acquire more data, 22 is more than 4, statistics

5 Building Science Contractors Selected, 22 homes

• Taitem Engineering (retrofit 4 houses)– Snug Planet

• NAHB – Research Center (retrofit 3 - 4 houses)– SIPA

• IBACOS (retrofit 8 houses, and 1 control)– Green Homes America

• Verdae (retrofit 3 houses) – Mulder Construction

• Levy Partnership (retrofit 3 houses, MF) – Sto Corp

Material Intensive in both directions …

Reduced Mechanical Systems enables energy reductions

Continuous Mechanical Ventilation that works

Homeowner Engagement, More Emphasis needed on promoting “comfort”

• Air quality• Safety (removal of auxiliary heat sources)• Insurance premiums (no ice damming, falling ice) • Building quality/integrity • Value the ‘resilience’ of the solution • Better sound attenuation (indoors is quiet) • Improves longevity of equity investment • Thermostat settings at occupant desired levels

Direct Benefits of Screwing 4” of Rigid to Exterior

• Works daytime, nighttime• Works summer, winter• Eliminates undesirable air leakage • Employs local labor• Invokes building permit, which brings house to code• Works when grid is de-energized • Works on cloudy days• Works when wind is not blowing

Long Ways away from a “Program” …

Allies Needed • Regulators• Bank appraisers • Code officials, consistency• Siding contractors• Realtors• Insurance underwriters• Project agent • Manufacturers discounts• Slush fund investment to

code comply homes

Policies Needed • Carbon taxes• Fuel oil taxes to fund

Bldg Science • kBTu/ft2/yr threshold • Reward for less

Contact…

• Greg Pedrick, C.E.M.Buildings R&D Project Manager17 Columbia CircleAlbany, NY 12203(518) 862-1090, x3378

gap@nyserda.ny.govhttp://nyserda.ny.gov/advanced-buildings