A Retrofit Strategy for
Aging Multi-unit Residential
Buildings in Toronto
Marianne Touchie
November 29th, 2012
Passive House Canada AGM
Outline
• Motivation for MURB energy retrofit research
• Performance issues and the status quo
• Current Research at the University of Toronto
including NTED™
2
Motivation for MURB retrofit research
Housing starts in the GTA
Housing Stock
30%
Residential GHG
Emissions
40%
Indoor Environmental
Quality Issues:
Draughts and overheating
High relative humidity
and mould growth
Transmission of smoke,
odours, noise, insects
3
Source: CMHC, Tower Renewal Guidelines
Causes of performance issues
Architectural
Minimal
Thermal
Resistance
Uncontrolled
Air Leakage
Thermal
Bridge
through Slab
4
Image source: Tower Renewal Guidelines
Causes of performance issues
Operational
+ +
+ +
+
+
+
+
+
+
+
+
+
+
+
+
+
+
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Causes of performance issues
Operational
Negative
Dynamic pressures
(wind, stack and
mechanical)
+
Architectural
Balanced
Loose envelope and
interior partitions
=
Uncontrolled
air flow
Positive
6
Current Retrofit Strategies
Overclad
Install PVs
Cost
Install solar
thermal
Replace
boiler
Enclose
balconies
Space Heating
Requirements
30%
Replace
windows
IEQ issues
remain
Replace
MAU
Upgrade
Submeter
HVAC
controls
Recaulk
Replace
windows
lighting
Install
sensors
Time Required for Implementation
Sources: Natural Resources Canada; Toronto Atmospheric Fund
IEQ issues
solved?
Existing
Building
Typical
Retrofit
Emerging Techniques
Compartmentalization
Reduced stack pressure
results in less infiltration
Corridor ventilation
remains insufficient
8
Source: CMHC 2005
Emerging Techniques
Suite-based Equipment
Preferred by condo owners,
building managers
In conjunction with a central
system and without
compartmentalization
9
Source: Finn Projects
Proposed Solution: NTED™
Combine emerging techniques with a
modified version of Nested Thermal
Envelope Design™ for single family homes
Apartment
18°C
Conduction and
Air Leakage
Heat
Recovery
Zone
0°C
Exterior
-6°C
Enclosed
Balcony
Ventilation Air Heating
Heat Transfer
Adiabatic and
Airtight
10
NTED™ Research Objectives
Determine the viability of
NTED™ application in the
MURB sector
Through monitoring, gather
detailed information about
MURB operation
Verify suite-level performance
through laboratory testing
Develop model with energy
simulation program
Image source: Tower Renewal Guidelines
Monitoring Program
35 Charles Street
Student Family Residences
Building-level and suite-level monitoring
12-month period
12
Monitoring Program
Building-level: Natural gas (hourly) and electricity
use (sub-hourly)
Suite-level: electricity use E
E
13
Monitoring Program
Building-level: Natural gas (hourly) and electricity
use (sub-hourly)
D
P D
D
D
Suite-level: electricity use E temperature T
relative humidity R
Selected suites: pressure differential sensors P
(at corridor, exterior, exhaust), displacement
sensors D window), ambient lighting sensors L
T/R
L
T/R
P
P
E
P
14
Laboratory Testing
Climate Simulator at the
University of Toronto
Cold Room
Chiller
Baffle
Enclosed
Balcony
HP
Apartment
HRV
Warm Room
15
Energy Modelling
Test various retrofit strategies
Envelope Types
Base Wall
R2000 Wall
Optimized Wall
Base Wall + Overcladding
New Wall + New Wall
In-Suite Mechanical components
Heat Recovery Ventilator
Heat Pump
Domestic Hot Water Tank
Sensitivity Analyses
Orientation
Fenestration-to-wall ratio
HRZ dimensions
Envelope air tightness
Envelope thermal resistance
Cooling season performance
16
Bringing it all together...
Building
Monitoring
Energy
Simulations
Laboratory Results
Laboratory
Results
Retrofit
Strategies for
MURBs
17
References
•
Canadian Mortgage and Housing Corporation. 1997. Energy Audits of High-Rise Residential
Buildings. Technical Series 97-100. from http://www.cmhcschl.gc.ca/publications/en/rhpr/tech/97100.htm
•
Canada Mortgage and Housing Corporation. 2005. “Assessment of Suite Compartmentalization and
Depressurization in New High-Rise Residential Buildings,” Technical Series 05-112.
•
Dixon, E., Pressnail, K.D., Richman, R., Touchie, M. 2010. Thermal Performance of the Exterior
Envelopes of Whole Buildings XI International Conference: NTED: An innovative design using nested
thermal envelopes to achieve significant reductions in energy use.
•
Finn Projects (Synchronicity Projects Inc.) 2003."Survey of In-Suite Space and Domestic Hot Water
Heating Systems in Multi-unit Residential Buildings," Canada Mortgage and Housing Corporation
Research Report.
•
Kesik, T. and Saleff, I., 2009. Tower renewal guidelines. Toronto: University of Toronto.
•
Natural Resources Canada. 2008. Comprehensive Energy Use Database Tables. [Online]. Available:
http://oee.nrcan.gc.ca/corporate/statistics/neud/dpa/trends_res_on.cfm
•
United Way. (2011) Vertical Poverty: Poverty by Postal Code 2. United Way Toronto.
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