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1.0: Utilizing Thermal Mass Advantages 2.0: Selection of the Insulation System 3.0: Thermal Bridging 4.0: Control of Air Infiltration
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Continuing
Education
Services
Thermal Performance of
Concrete Masonry
Presentation #: 000502-01 NCMA
Continuing
Education
Services 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.
AIA Disclaimer Notice
Continuing
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Thermal Performance of
Concrete Masonry
1.0: Utilizing Thermal Mass Advantages
2.0: Selection of the Insulation System
3.0: Thermal Bridging
4.0: Control of Air Infiltration
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•Approximately 22% of the total energy
consumed for building operations is used
to heat and cool commercial structures.
•About 25% is used to heat and cool
residential structures.
Thermal Performance of
Concrete Masonry
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Thermal Mass
Advantages
1.0 Thermal Mass Advantages
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1.0 Effects of Environment
on System Performance
Thermal & Energy
Heat Gain / Loss
Interior Moisture
Reduced Energy Efficiency
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1.0 Utilizing Mass Advantages
Thermal Performance of masonry depends
on its thermal resistance (R-Value) as well
as thermal mass.
• Size and Type of Unit
• Type and Location of Insulation
• Finish Materials
• Density of Masonry
R-Value of
masonry
is determined
by the
following
characteristics
Continuing
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Services THERMAL MASS: Materials with mass
heat capacity and surface area are
capable of affecting building loads by
storing and releasing heat as the interior
and/or exterior temperature and radiant
conditions fluctuate.
Thermal mass tends to decrease both
heating and cooling loads in a given
building.
1.0 Utilizing Mass Advantages
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1.0 Utilizing Mass Advantage
The effectiveness of thermal Mass is
dependent upon:
•Climate
•Building Design
•Insulation Position
•Wall Heat Capacity
•Fenestration,
•Occupancy,
•Orientation
•Heat Sources
Commercial
buildings
have peak
loads during
the average
work day
9:00 - 5:00
Residential
buildings
have peak
loads that
start earlier
and last later
into the
evening
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1.0 Utilizing Mass Advantages
Buildings constructed with masonry can
require 18% - 70% less insulation than
similar frame buildings, while still
providing an equivalent level of energy
efficient performance.
Thermal storage is the temporary storage
of high or low temperature energy for later
use. It allows a time gap between energy
use an daily availability. Using thermal
storage, heating or cooling energy is stored
so that it is available for space conditioning
during peak demand periods.
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1.0 Utilizing Mass Advantages
Proper
management of a
building’s thermal
storage has
resulted in 10-35%
reductions in
peak electrical
use in commercial
buildings.
This
standard
allows
owners and
builders to
take
advantage of
thermal
mass to
reduce the
requirement
for added
insulation.
ASHRAE/IES
Standard 90.1 =
Energy Standard for
Buildings
Except Low-Rise
Residential Buildings.
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0
1
2
3
4
5
6
7
8
9
Non-
residential
High-rise
residential
Semi-heated
(Warehouse)
Masonry Bldg
Steel Frame
Bldg
SAN FRANSISCO
Minimum
R-Value
ASHRAE
90.1
The standard
recommends
a maximum
glass area
of 50%.
If smaller
areas of
fenestration
are used, a
further
reduction in
R-value can
be provided
with the use
of masonry
1.0 Thermal Mass Advantages
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0
1
2
3
4
5
6
7
8
9
Non-residential High-rise
residential
Semi-heated
(Warehouse)
Masonry Bldg
Steel Frame
Bldg
PHOENIX
Min
imu
m
R-V
alu
e
1.0 Thermal Mass Advantages
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Selection of Insulation
Materials
2.0 Selection of Insulation Materials
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Services Criteria for insulation selection
•Desired Thermal Properties
•Climate Conditions
•Ease of Construction
•Cost
•Additional Design Criteria
2.0 Selection of the Insulation System
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Representative R-Values for 8 in. Normal Weight Concrete Masonry Units
Loose-fill insulation Polyurethane
Perlite Vermiculite foamed insulation Solid grouted
density range mid range mid range mid range mid
Exposed 85 6.3-8.2 7.1 5.9-7.5 6.6 6.9-9.4 8.0 1.9-2.1 2.0
block, 95 5.3-7.2 6.1 5.0-6.7 5.7 5.8-8.1 6.7 1.7-2.0 1.8
both 105 4.5-6.3 5.2 4.3-5.9 4.9 4.8-7.0 5.6 1.6-1.9 1.7
sides 115 3.8-5.5 4.4 3.7-5.2 4.3 4.0-6.0 4.7 1.5-1.8 1.6
125 3.2-4.8 3.8 3.1-4.6 3.7 3.3-5.1 4.0 1.5-1.7 1.5
135 2.7-4.2 3.3 2.7-4.0 3.2 2.8-4.4 3.4 1.4-1.6 1.5
2.0 Selection of the Insulation System
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Wall Assemblies
Interior Insulated Wall
This strategy moderates the effect
of exterior temperature swings on
the building’s interior
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Exterior Insulated Wall
Thermal mass is most effective
when insulation is placed on the
exterior of the masonry wall.
This strategy keeps masonry
directly in contact with interior
conditioned air.
Wall Assemblies
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CAVITY WALL
Wall Assemblies
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Core Insulated Wall (Inserts)
Wall Assemblies
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2.0 Selecting Insulation
Continuing
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Services Insulation
Strategies
2.0 Selecting Insulation
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Wall Assemblies
Core Insulated Wall (Loose-fill / Expanded foam)
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Strategies
2.0 Selecting Insulation
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Services Insulation
Strategies
2.0 Selecting Insulation
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3.0 Thermal Bridging
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Thermal bridging occurs when a
relatively small area of the wall,
floor, or roof loses more
heat than the surrounding area.
A thermal bridge allows to heat to short
circuit insulation
Thermal bridging is associated with
conduction heat transfer, where heat flows
through solid materials from warmer to
colder areas.
3.0 Thermal Bridging
Continuing
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Services Wall Design
Considerations
Pathways
1. Intersection @ Parapet and Roof
2. Intersection @ 2nd Floor
3. Intersection @ Slab
4. At-Grade / Retaining
3.0 Thermal Bridging
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Thermal bridges can occur at:
•Where building elements are joined
•Improper installation of materials
•Through materials that are good conductors
•Floors, roofs, beams
• Gaps in insulation
•Nails, steel framing
THERMAL CONDUCTIVITY
ability of
masonry to
conduct heat
Lightweight
units 2.5 (80
pcf)
Heavy weight
8.3 (140 pcf)
3.0 Thermal Bridging
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Possible Effects of Thermal
Bridging
•Increased heat loss
•Local cold spots on the interior
•Condensation
•Damage to insulation
3.0 Thermal Bridging
Continuing
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Services Thermal bridging effects can be
magnified by heat and moisture
transfer due to air movement.
Proper installation of vapor and air barriers can greatly
reduce moisture damage caused by thermal bridging.
3.0 Thermal Bridging
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1. REDUCE TANSFERENCE
OF MOISTURE THROUGH
WEBS
2. INCREASE THERMAL
PERFORMANCE
3. REDUCE LABOR
INTENSITY
3.0 Thermal Bridging
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4.0 Control of Air infiltration
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Air infiltration is undesirable air
leakage into conditioned
spaces of buildings. Its direct
result is an increase of energy
consumption to maintain
desired levels of human
comfort.
Infiltration can come from a
myriad of cracks, gaps, poorly
designed joints, flashing, utility
penetrations and window and
door frames.
4.0 Control of Air infiltration
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Control of Infiltration
Masonry structures do
not have sill
plates as wood frame
buildings do.
Masonry construction is
a continuous
assembly. This means
that infiltration
is significantly reduced
in a masonry
structure
Infiltration
accounts for
40% of the
total heating
and cooling
load for the
average
house.
Based on
research, the
use of a
waterproofed
masonry wall
can reduce
infiltration by
87%
4.0 Control of Air infiltration
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10%
11%
15%
2%
13%4%
14%
31%
Windows
Doors
HVAC
Elec. Outlets
Pipes
Vents
Fireplace
Wall, Sill, Ceiling
Distribution of leakage areas by component
systems
COST vs
BENEFIT
Simply
increasing
R-value
becomes
less
economical.
Required
changes in
construction
practices
must be
considered.
4.0 Control of Air infiltration
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Wall Strategies
1
2
3
4
1. Indoor vapor retarder in cold
climates. Delete in hot, humid
climates.
2. Adhesive attachment
preferred (mechanical
attachments optional).
3. Caulk or foam joints
between board insulation.
4. Caulk and seal utility
penetrations.
4.0 Control of Air infiltration
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