Deep Energy Retrofit (DER) Workshop January 12, 2013 Sustainable Living Resource Center Cottekill,...
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Transcript of Deep Energy Retrofit (DER) Workshop January 12, 2013 Sustainable Living Resource Center Cottekill,...
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
[email protected]://nyserda.ny.gov/advanced-buildings