Metromont CEFPI 3.29.11 (NXPowerLite).ppt [Compatibility Mode]

Energy Analysis of School Projects
2011 Southeast Region Conference
Savannah, Georgia
March 29, 2011
Presented by
Terry Gladden, RA
George Spence
Angela San Martin
P.E., LEED® AP
AIA/CES Program Purpose
Program Title: Energy Analysis of
School Projects
Program #
Provider #
Provider Name:
Learning Units:
SE 15-11
F118
CEFPI
1.0 HSW
“Conference of Educational Facility Planners International”
(CEFPI) is a Registered Provider with The American
Institute of Architects Continuing Education Systems.
Credit earned on completion of this program will be
reported to CES Records for AIA members. Certificates of
Completion for non-AIA
non
members are available on request.
This program is registered with the 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.
Learning
The
BasicsObjectives
of Precast/Prestressed Concrete
1. Understand how owner/design team can increase building envelope
thermal efficiency to achieve advanced energy design in K -12 schools
2. Explain methods available to audit and reduce energy costs by use of
case studies
3. Explore how to design high performance exterior wall systems with
continuous insulation and thermal mass
4. Understand the concepts of sustainability in K -12 schools and how to
lower life cycle energy costs
Largest School System in Georgia
Gwinnett County
Public School
System is the
largest in Georgia
with a student
population of
160,000 housed in
115 K-12 facilities.
Largest School System in Georgia
Standard sizes (student capacity)
of facilities in Gwinnett County are
as follows:
Elementary Schools: 1100
Middle Schools: 1800
High Schools: 3000
Energy Audit Suggestions
Standard HVAC System : Water source
heat pump system that utilizes a
separate heat pump for each classroom
or major space in the building.
Outside air is introduced through
conventional Energy Recovery Units.
Air quality is accomplished through the
use of bi-polar
polar ionization devices.
Energy Audit Suggestions
The system is controlled by a
computer driven energy
management system, which
controls both temperature and
humidity, and keeps the units
turned off when not needed.
Energy Audit Suggestions
Gwinnett Schools makes use of
T-8
8 light fixtures with electronic
ballast, LED exit lights and
occupancy sensors that turn off
the lights and the HVAC when a
room is unoccupied.
Energy Audit Suggestions
Energy Audit Suggestions
Energy Audit Suggestions
•Change
Change all HVAC filters 6 times per year.
•Monitor
Monitor and maintain the optimum chemical levels in
cooling towers and loops to prevent corrosion and
bacterial contamination
•Regular
Regular cleaning of the coils in the WSHP’s and
refrigeration equipment.
•Scheduled
Scheduled PM on all equipment as recommended by
manufacturer.
Energy Audit Suggestions
Gwinnett County Public School
System’s standard practice is to
design and build multi-story
multi
buildings in compact designs,
thus minimizing
roof area and
exterior wall area.
Gwinnett School of Mathematics, Science and Technology
Energy Audit Results
KBtu/Sq. Ft./ year
Elementary Schools :
Middle Schools:
High Schools:
2009
38
41
44
Twin Rivers Middle School
2010
35
36
40
% lower
8%
12%
9%
Energy Audit Results
Twin Rivers Middle School floor plan (3 level classroom wing on right)
Energy Audit Results
Case Study of Four
Gwinnett Middle Schools
S.F.
Twin Rivers MS
North Gwinnett MS
Lanier MS
Trickum MS
231,728
241,350
241,350
241,350
Students
1,422
1,793
1,154
1,359
Energy Audit Results
Gwinnett Middle School Energy Use Comparisons
Year Ending 12/2010
40
kBtu/s.f.
kBtu/s.f.
50
Twin Rivers
North Gwinnett
Lanier
Trickum
30
20
25 Middle Schools
Energy Audit Results
Annual Energy Use For Four
Gwinnett Middle Schools
Total Energy
kBtu/SF
Twin Rivers MS
North Gwinnett MS
Lanier MS
Trickum MS
Average MS
Highest using MS
27.0
31.5
32.0
32.5
33.0
48.0
% above
Twin Rivers
17%
18%
20%
33%
78%
Total Precast Schools
Why Precast?
§ Energy Efficient Results
§ Virtually eliminates
mold & mildew
§ Low maintenance
Benefits of Total Precast School Building Systems
§ Speed of construction
§ Proven and cost effective
§ Architectural finish options
§ Built-in structural integrity
§ Fireproof structure
§ Plant manufactured reliability
Construction of Total Precast Schools
Middle School
Twin Rivers Middle School
Gwinnett
County
Public
Schools
Gwinnett
County
Public
GA
Schools, Buford, Buford,
GA
231,728 s.f.
Erected in Three Months
Three Story Classroom Wing
Total Precast Schools
Twin Rivers Middle School
Viewspace
acrossduring
4 classrooms
Open, clear
construction
Bid Price: $23,180,000
$100/sf project
10%-15% less than
brick & block method
Demising Walls
are concrete block for flexibility
Same area with walls and finishes
Total Precast Schools
Main Hallway
View across 4 classrooms
Demising Walls
are concrete block for flexibility
Twin Rivers Middle School
Total Precast Schools
Media Center
Demising Walls
are concrete block for flexibility
Twin Rivers Middle School
Up Front MEP Coordination is Critical
MEP Installation, suspended from
Double Tees
Speed of Completion
Twin Rivers Middle School turned over eighteen months after notice to proceed
Finished six months ahead of
Mountain View High School
next door, started at same time.
Cunningham Forehand Matthews
& Moore Architects
Building with limited site lay-down
lay
area and
access
March 3, 2009
Gwinnett County Public Schools
Buford, GA
May 29, 2009
210,000 s.f. erected in 52 Work Days
Adjacent to Occupied Classrooms
Panelization of load-bearing
bearing walls
Classroom Wings: load bearing thermal efficient wall panels with punched openings
Panelization of load-bearing
bearing walls
Classroom Wing:
§ Exterior load bearing thermal efficient wall panels with punched openings
§ One piece: ~12'-0" x 45'-0"
§ Supports double tee floor and roof system
§ Area under roof: ~19,200 SF
§ Time to erect precast envelope: ~8 days
Building section
Classroom
Corridor
Classroom
Section – Typical Two-wide
Two
Classroom Wing
Walls and one line column & beams with two spans of double tees.
(Non-precast
precast corridor walls are CMU or metal studs & sheet rock.)
Detailing Thermal Efficient Wall Panels
Definition of Continuous Insulation (c.i.)
ASHRAE
90.1 – 2007
ACI per
Design
Award Winner
Continuous Insulation
around perimeter of
building.
Concrete Wall Panel
nearly perfect “ci”
“Insulation that is continuous across all structural members without
thermal bridges other than fasteners and service openings.”
Detailing Thermal Efficient Wall Panels
ACI Design Award Winner
No Solid Zones – (C.I.)
Solid Zones
Solid zones reduces R-Value
Value by as much as 50%
Detailing Thermal Efficient Wall Panels
Window/Door Head and Sill
No Solid Zones – (c.i.)
Use wood blocking or necked-down
necked
insulation
Detailing Thermal Efficient Wall Panels
Corner Detail with c.i.
Return insulation at corner conditions to continue c.i.
Detailing Thermal Efficient Wall Panels
ACI Design Award Winner
Foam
Wall Panel at Roof Insulation (c.i.)
Return insulation through interior concrete wythe
to meet roof insulation for c.i.
Detailing Thermal Efficient Wall Panels
ACI Design Award Winner
§ Foam joint to
equal wall R-value
R
Foam
§ Backer rod
§ Sealant
Corner Detail with c.i.
Install insulation at wall panel joints prior to caulking.
R-Value
Value of joint treatment should equal that of the wall.
High Performance Thermal Efficient Wall
Insulated Wall Panels
Thickness
6” to 14” max.
R-Value
R-4 to R-35, typically R-12
Mass Walls
Non-Residential Insulation min. R-5.7ci
Continuous insulation
side-to-side, top-to-bottom.
12'
12'-0"
or 13'-4"
Insulation
Carbon Fiber Wythe Connector
Exterior
2"
Varies
2" w/o Reveals
2 ½" with Reveals
Concrete Pilaster (coincides with haunch for DT)
Steel Mesh
Interior
Section - High Performance, Fully Composite Precast Wall System
High Performance Thermal Efficient Wall Panels
Benefits of carbon grid trusses:
§ Continuous insulation to all edges of the panel
§ No thermal bridging
§ Non-corrosive
§ Strong - over 6 times the tensile
strength of steel reinforcing
High Performance Insulation System
Total Precast Building System
Designing Precast Wall Systems
§Load bearing and non-load
load bearing
§Insulated R-4 to R-35
§Fire Rated – no on-site
site fireproofing
§Sound Isolation (8" wall = 58 STC)
§Interior paint ready surfaces
§Electrical conduit and boxes cast in
Architectural Finishes & Brick Veneer
§
§
§
Reveals
Thin Brick
Form liner
§
§
§
Sandblast
Retarded Aggregate
Dimensional Stone
Brick Patterns and Mortar Joints
Running Bond
Racked Joints
Flemish Bond
Stack Bond
Concave Joints
Common Bond
Traditional Brick Face Dimensions
§ Modular Brick Coursing:
§ 2 ¼" H x 7? " L with ? " joint
§ Vertical coursing: 3C = 8 inches
§ To reduce costs:
§ Eliminate corner brick at jambs, head
§
§
and sill
Minimize cut brick
Design the elevation down to half brick
Designing Precast Wall Systems with Brick
Manufacturing Process
§ Install brick formliner
§ Place bricks
§ Set reinforcement
§ Place concrete and insulation as required
Cast-in Thin Brick Veneer
Total Precast Building System
Cast-In
In Brick: Manufacturing
Cast- In Brick Mfg. Process
1. Clean form, layout exterior
facade
2. Place brick, reveals,
openings, etc.
3. Rebar and prestressing
strand is placed
4. Concrete for outer wythe
is placed
5. Insulation is set
6. Concrete for inside wythe
is placed
7. Cure, remove, clean &
store for shipping
Min. 5,000 psi concrete in-lieu of 750 to
1200 psi mortar, water migration through the
exterior wythe is not an issue
Designing Precast Wall Systems with Brick
Cast-in Thin Brick
§ Actual clay masonry products are cast directly
into the concrete panels:
§ Min. 5,000 psi concrete vs. 750 psi to
2,500 psi mortar
§ Superior durability
§ Ease of maintenance
§ Design flexibility
§ Low moisture absorption <5%
Cast-in Thin Brick Veneer
Total Precast Building System
Designing Precast Wall Systems with Brick
Cleaning, Storage and Delivery Preparation
§ Pressure wash panels
§ Store at manufacturing plant
§ Load day before installation
§ “Just In Time" delivery
Speed of Installation – 28' tall wall comparison
§ Precast
4,032 SF installed in one day
§ Brick & Block Cavity Wall
400 SF installed in one day
Cast-in Thin Brick Veneer
Total Precast Building System
Precast Wall System vs. Cavity Wall System
Limitations of mortar set brick:
§ Building codes severely limit use
due to wind and seismic loads
§Significant
Significant maintenance problems
§Water penetration is problem
Precast Wall System vs. Cavity Wall System
Precast Walls
§ Manufactured in controlled environment
§ Precast is impervious to water & air
§ No voids or cavities
§ Less opportunities for mold and mildew:
no food source, moisture or interior cavity
Brick & Block Cavity Walls
§ Designed as a "wet wall" system
§ Mortar joint – 750 to 2,500 psi
§ Typical field installation includes:
concrete block, waterproofing, insulation,
lintels, masonry ties, weep holes and brick
§ Weep holes must stay clear during
construction to properly remove moisture
Brick Veneer
Interior concrete
wythe - with
paint ready
surface
Concrete
Insulation
Precast Wall Detail
Concrete
block – interior
wall surface
Brick Veneer
Mortar Joint
Insulation
Air Space
Cavity Wall Detail
Precast Wall System vs. Cavity Wall System
Concrete
block – interior
wall surface
Brick Veneer
Brick Veneer
Concrete
Insulation
Interior concrete
Wythe - with
paint ready
surface
Precast Wall Detail
Mortar Joint
Insulation
Air Space
Cavity Wall Detail
Joint Comparison – 30' high x 200' long wall with no openings
§ Precast wall system with brick
§ 480 LF of panel to panel joints (sealant)
§
Cavity wall with brick veneer
§ 36,308 LF of mortar joints
§ 120 LF of control joints
Note:
The smaller footprint of the precast
wall can contribute to a decrease in
the gross SF of the building footprint
Sustainability of Precast Concrete
Sustainability:
Hepatica
3/6/10
Sustainability of Precast Concrete
Sustainability:
Our capacity to endure.
The Pantheon
Sustainability of Precast Concrete
Sustainability –
our capacity to endure.
During Construction:
§ Local materials, recycled steel, fly
ash
§ No jobsite waste, no site
disturbance
§ Low embodied energy
Sustainability of Precast Concrete
Sustainability –
our capacity to endure.
During Construction:
§ Local materials, recycled steel, fly
ash,
§ No jobsite waste, no site
disturbance
§ Low embodied energy
Henceforth:
§ Reduced energy for heating &
cooling
§ Fire proof, storm proof structure
Sustainability of Precast Concrete
Sustainability –
our capacity to endure.
During Construction:
§ Local materials, recycled steel, fly
ash,
§ No jobsite waste, no site
disturbance
§ Low embodied energy
Henceforth:
§ Reduced energy for heating &
cooling
§ Fire proof, storm proof structure
§ Low maintenance
Sustainability of Precast Concrete
Sustainability –
our capacity to endure.
During Construction:
§ Local materials, recycled steel, fly ash,
§ No jobsite waste, no site disturbance
§ Low embodied energy
Henceforth:
§ Reduced energy for heating &
cooling
§ Fire proof, storm proof structure
§ Low maintenance
§ Recyclable
Sustainability of Precast Concrete
Sustainability –
our capacity to endure.
Research studies reveal:
§ Energy to operate building is 9-to
to-1
over energy to construct building
§ The most cost-efficient green
buildings are those that are supersuper
insulated
§
Focus on eliminating thermal
“bridging” between the interior and
exterior pays
High Performance Thermal Efficient Wall Panel
üInsulation from edge-to-edge
edge and top-totop
bottom
üThermal Mass
üLoad Bearing
üImpervious to water penetration
üAir barrier
üEffective vapor barrier
High Performance Thermal Efficient Wall Panels
§
Minimum R-values are
determined by ASHRAE
90.1 energy code
§
Advanced Energy Design
per ASHRAE 189.1
requires
exceeding 90.1 by 30%
§
Basis for LEED points
ASHRAE 90.1
8 Climate Zones for USA
High Performance Thermal Efficient Mass Walls
High Performance Thermal Efficient Wall Panels
R- 7.6 “ci” for mass walls
High Performance Thermal Efficient Wall Panels
Advanced Energy Design, ASHRAE 189.1
Climate Zone
90.1
Advanced
Zone 2
5.7
7.6
Zone 3
7.6
9.5
Zone 4
9.5
11.4
High Performance Thermal Efficient Mass Walls
Net-Zero-Energy
Energy Building
Thermal Mass
Research study shows 16% savings for precast clad c.i.p.
frame building vs. steel frame/metal stud wall is Climate
Zone 3
High Performance Thermal Efficient Mass Walls
Time Lag
Damping
Thermal mass
§ Delays the peak heating/cooling loads
§ Reduces peak energy requirement
§ Smaller investment in HVAC equipment
Water Vapor Transmission
Outside
Inside
2” Concrete
4” EPS
Temperature differential, relative
humidity and the “permeance” profile,
can be used to calculate
dew point in the wall.
.68 .20 16.0 .20 .25
Component R-Values
Actual Temperature
Dew Point Temperature
Water Vapor Transmission
Season: Winter
70 oF Inside
30% RH
30 oF Outside 50% RH
Material Properties:
Concrete R 0.08/in, 3.2 perm-in
EPS
R 4.00/in, 2.0 perm-in
Actual Temp.
80
Dew Point Temp
20
10
Exterior Air Film
30
2" Concrete
40
4"
4”XPS
EPS
50
2" Concrete
Temperature (F)
60
Interior Air Film
70
0
No Condensation Potential
Water Vapor Transmission
Season: Summer
70 oF Inside
30% RH
90 oF Outside 80% RH
Material Properties:
Concrete R 0.08/in, 3.2 perm-in
EPS
R 4.00/in, 2.0 perm-in
Actual Temp.
100
Dew Point Temp
90
30
20
10
Exterior Air Film
40
2" Concrete
50
4"EPS
XPS
4”
60
2" Concrete
70
Interior Air Film
Temperature (F)
80
0
No Condensation Potential
Water Vapor Transmission
If dew point occurs in wall, add vapor barrier
§ The proper location of vapor
barriers:
§ In cold climates, located to the
warm inside surface.
§ In hot /humid climates, to the
warm outside surface.
§ In temperate climates, perhaps
omitted.
Thermal Imaging Survey Results
Atlantic Southeast Infrared
“We are your eyes to the invisible.”
www.ASInfrared.com
1-770-570
570-9035
1505 Logan Circle, Cumming GA 30041
E-Mail:
Mail: Info@ASInfrared.com
Thermographic Report
Report Date: 3/08/2011
Twin Rivers Middle School
Thermal Imaging Survey Results
Twin Rivers Middle School Cafeteria Wall
Inside looking out
Outside looking in
Interior finishes
Insulated precast wall
Thermal Imaging Survey Results
Thermal imaging determined the
Twin Rivers Middle School precast walls
to be
“very energy efficient”
with an observed R-Value
R
of 18.6
Twin Rivers Middle School Media Center Wall, exterior
Thermal Imaging Survey Results
North Gwinnett Middle School Cafeteria Wall
Inside looking out
Interior finishes
Outside looking in
Brick & block cavity wall
Thermal Imaging Survey Results
Thermal imaging determined the
North Gwinnett Middle School brick & block cavity
walls
to be
“energy efficient”
with an observed R-Value
R
of 15.0
Gwinnett Middle School elevation
Thermal Imaging Survey Results
Lanier School Cafeteria Wall
Inside looking out
Interior finishes
Outside looking in
Brick & block cavity wall
Thermal Imaging Survey Results
Thermal imaging determined the
Lanier Middle School brick & block cavity walls
to be
“energy efficient”
with an observed R-Value
R
of 13.2
Lanier Middle School elevation
Thermal Imaging Survey Results
Trickum Middle School Classroom Wall
Inside looking out
Interior finishes
Outside looking in
Brick & block cavity wall
Thermal Imaging Survey Results
Thermal imaging determined the
Trickum Middle School brick & block cavity walls
to be
“energy efficient”
with an observed R-Value
R
of 12.7
Trickum Middle School elevation
Thermal Imaging Survey Results
Actual R-Value
Value as measured by
Infrared Imaging of walls
Total Energy
kBtu/SF
Twin Rivers MS
North Gwinnett MS
Lanier MS
Trickum MS
Average MS
Highest using MS
27.0
31.5
32.0
32.5
33.0
48.0
Measured
R-Value
R-19.2
R-15.0
R-13.2
R-12.7
Review: Energy Analysis of School Projects
§
§
§
§
Audit and follow-up procedures
produces results
A thermal efficient design is an
effective way to reducing
energy costs
Review of state-of-the-art high
performance exterior walls
Sustainable design will lower
life cycle costs
Thank You for Your Time!
This concludes the
American Institute of Architects
Continuing Education Systems
Program.
2011 Southeast Region Conference