Deep Energy Retrofit of a High-Rise MURB
29
Deep Energy Retrofit of a High- Rise MURB COLIN SHANE | M.Eng., P.Eng. RDH BUILDING SCIENCES INC. SAN FRANCISCO, CA
-
Upload
rdh -
Category
Engineering
-
view
338 -
download
4
Transcript of Deep Energy Retrofit of a High-Rise MURB
Deep Energy Retrofit of a High-Rise MURB
COLIN SHANE | M.Eng., P.Eng. RDH BUILDING SCIENCES INC. SAN FRANCISCO, CA
AIA Credits
National Institute of Building Sciences – Provider #G168 Credit(s) earned on completion of this course will be reported to AIA CES for AIA members. Certificates of Completion for both AIA members and non-AIA members are available upon request. This course is registered with AIA CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. ___________________________________________ Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.
AIA Credits – Learning Objectives
Participants will: 1. Learn how to link the performance of individual building enclosure components in a holistic framework to achieve high-performance buildings.
2. Explore, through built case studies, how building envelope design determines overall energy conservation and sustainability capabilities 3. Learn innovative practices for avoiding heat loss as well as moisture and air infiltration in enclosure design for healthy new and existing buildings. 4. Understand the role of building enclosure commissioning in the design, construction, and operation and maintenance of commercial facilities.
4 of
Outline
à Why multifamily buildings?
à Energy consumption & opportunities for conservation
à Case study of an energy efficient multifamily retrofit
5 of
à Growing proportion of the housing stock
à Large emitters of GHGs in cities à 55% of GHGs from Buildings in Vancouver
à Many challenges – split incentives, poorly insulated
envelopes
Why Multifamily Buildings?
6 of
0
50
100
150
200
250
300
81
14
4 95
24
26
16
31
8 76
21
22
61
93
33
22
04
52
91
74
36
03
12
8 61
4 33
9 25
730
41
24 1
40
59
21
36
58
Annual
Ener
gy
Use
Inte
nsi
ty,
kW
h/m
2
Building ID
Gas Electricity - Common Electricity - Suite
Average MURB EUI
à Pacific Northwest Average EUI: 68 kbtu/sf per year
Energy Consumption and Conservation in Mid- and High-Rise Residential Buildings http://www.hpo.bc.ca/sites/www.hpo.bc.ca/files/download/Report/MURB-EnergyStudy-Report.pdf
68 kbtu/sf
7 of
102
38
10
0
20
40
60
80
100
120
Current Average Good Retrofit Best Retrofit
Spac
e H
eati
ng E
UI,
kW
h/m
2Multifamily Energy Efficiency Opportunities
90% Less Space Heat Energy
60% Less Space Heat Energy
Good Retrofit
• Wall insulation to R-10
• Windows double glazed, argon fill, low-e, low conductive frame
• Air sealing
Best Retrofit
• Wall insulation to R-18
• Windows triple glazed, argon fill, low-e, low conductive frame
• Air sealing
• Heat Recovery Ventilation
32 kbtu/sf
12 kbtu/sf
3 kbtu/sf
8 of
The Approach: Passive Design
à Reduce the demand for heating, cooling and ventilation
energy through passive design strategies
à Well-insulated building
enclosure: walls, roof,
windows
à Airtight construction
à Heat recovery ventilation
à Combine with planned renewals work for cost-effectiveness
9 of
Case Study: Deep Energy Multifamily Retrofit
à Started with a condition assessment à Progressed to full building enclosure renewal,
incorporating energy efficiency measures
BE Upgrades
1 year M&V
Mechanical upgrades
1 year M&V
Monitoring & Testing
Project Timeline
Year 2011 2012 2013 2015 & ongoing
10 of
à 13 storey multifamily
residential building in
Vancouver, BC
à 37 two-bedroom units
à Constructed in mid 1980s
à Building renewals pursued at
decision of owners to
upgrade original building
enclosure
Case Study Background
11 of
Existing Building Enclosure Assessment
à Exposed concrete walls, non-
thermally broken aluminum
frame double glazed windows
à Some window interface water
leaks, air leakage
à Some concrete damage and
concerns with PT cables
à Existing walls R-4
à Existing windows R-1.8
Fig. 1.1 Original detail drawing of a window head and sill, coloured.
12 of
Existing Mechanical System Assessment
à Original mechanical systems
largely in place
à Electric baseboard heating
à Gas-heated make-up air for
ventilation (to corridors)
à 14 decorative gas fireplaces
at upper floor suites – some
replaced by owners
à Hot-water boiler & tanks
replaced few times before
13 of
à Replace aging building
enclosure components à Primarily windows
à Repair water ingress issues
à Improve durability and
reduce future maintenance
costs
à Improve comfort in suites
à Create a modern aesthetic
à Increase property value
à …and save some energy
Building Enclosure Renewal – Primary Drivers
14 of
Typical Year Energy Consumption
à Metered energy consumption 71 kbtu/sf per year à Total energy costs $66,000/yr ($1,800/suite)
à Only 36% paid directly by suite owners, balance paid within
condo fees
-‐
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
Mon
thly Ene
rgy Co
nsum
ption, ekW
h Suite Electricity, kWh Common Electricity, kWh Gas, ekWh
Gas46%
Suite Electricity
36%
Common Electricity
18%
Annual Breakdown
15 of
0
50
100
150
200
250
300
81
14
4 95
24
26
16
31
8 76
21
22
61
93
33
22
04
52
91
74
36
03
12
8 61
4 33
9 25
730
41
24 1
40
59
21
36
58
Annual
Ener
gy
Use
Inte
nsi
ty,
kW
h/m
2
Building ID
Gas Electricity - Common Electricity - Suite
Benchmarking Against Multifamily Buildings
à Pre-retrofit EUI: 71 kbtu/sf per year
Energy Consumption and Conservation in Mid- and High-Rise Residential Buildings http://www.hpo.bc.ca/sites/www.hpo.bc.ca/files/download/Report/MURB-EnergyStudy-Report.pdf
68 kbtu/sf
16 of
Evaluating Existing Building Energy Consumption
à Building energy model calibrated to metered data
to evaluate energy consumption by end-use and
potential Energy Efficiency Measures
Electric Baseboard Heating22%
Fireplaces9%
Ventilation Heating25%
Hot Water11%
Lights -‐ Common2%
Lights -‐ Suite7%
Plug and Appliances (Suites)8%
Equipment and Ammenity (Common)
16%
17 of
Case Study: Window Replacement
à Options: à Double glazed, metal frame windows
(minimum code requirement)
à Double glazed, low conductivity frame
à Triple glazed, low conductivity frame
Window Estimated Annual Energy Savings
Estimated % Savings
Double Glazed, Aluminum Frames
$1,900 3%
Double Glazed, Fibreglass Frames
$7,600 7%
Triple Glazed, Fibreglass Frames
$11,000 10%
18 of
Case Study: Window Replacement
à Incremental Payback à Choosing a more energy efficient window will
pay back in energy savings
à Double or triple glazed windows with low
conductivity frames compared to code minimum
à Incentive programs help offset cost, improve
payback
Simple Payback Simple Payback Including Incentives
Double Glazed, Fibreglass Frames
5 years <1 year
Triple Glazed, Fibreglass Frames
14 years 6 years
19 of
Building Enclosure Renewals Performed
à Over clad and exterior insulate
walls (R-16 effective)
à New R-6 tripled glazed fiberglass
windows
à New roof and deck membranes
à Improve air-tightness à Overall new enclosure R-value
R-9.1 vs R-2.8 original
à Next – Ventilation retrofit
Existing
Upgraded
20 of
Building Enclosure Renewals
à $3.6M renewals project, 7
month construction period
à Work primarily from exterior
with access to suites for
window installations
21 of
Exterior Insulation, Stucco & Metal Panel Overcladding
22 of
Triple Glazed Fiberglass Frame Windows
23 of
Completed Building Enclosure Renewals
24 of
Measured Savings
à 33% electricity savings
-
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Ele
ctri
city
Con
sum
pti
on
, kW
h Calibrated Model Pre-Retrofit Calibrated Model Post-Retrofit
25 of
-
50
100
150
200
250
Pre-Retrofit Post-Retrofit
EUI, k
Wh/m
2
Miscellaneous Electrical LightsHot Water Ventilation HeatingFireplaces Electric Baseboard Heating
Calibrated Model Annual Energy Savings
Measured Savings:
à 63% electric
baseboard heating
à 20% gas fireplaces
à 33% electricity
à 2% gas
à 19% total energy
= 215 MWh per year
225 177 19%
Savings
71 kbtu/sf 56 kbtu/sf
26 of
0
50
100
150
200
250
300
81
14
4 95
24
26
16
31
8 76
21
22
61
93
33
22
04
52
91
74
36
03
12
8 61
4 33
9 25
730
41
24 1
40
59
21
36
58
Annual
Ener
gy
Use
Inte
nsi
ty,
kW
h/m
2
Building ID
Gas Electricity - Common Electricity - Suite
Benchmarking Against Multifamily Buildings
à Pre-retrofit: 71 kbtu/sf per year
à Post-retrofit: 56 kbtu/sf per year
Energy Consumption and Conservation in Mid- and High-Rise Residential Buildings http://www.hpo.bc.ca/sites/www.hpo.bc.ca/files/download/Report/MURB-EnergyStudy-Report.pdf
68 kbtu/sf
27 of
à HRVs to provide direct continuous ventilation to
each suite
à Suite compartmentalization – air sealing between
adjacent suites and corridors
à Measure energy savings à Impact on occupants opening windows and space
heating energy?
Next – Proposed Heat Recovery Ventilators
28 of
Outcomes
à Measured 19% overall energy savings through passive design retrofit
à 63% electric baseboard heating savings
à Energy efficiency measures implemented at the time of planned renewals keep the incremental cost of upgrades low
à Replicating the success of this project is an opportunity for the entire industry
