today’s masonry wall · 2018. 4. 19. · today’s masonry wall a synergy in systems name: mark...
TRANSCRIPT
Today’s Masonry Wall
A SYNERGY IN SYSTEMS
Name: Mark Erickson
Provider #: H366
Title: Today’s Masonry Wall: Synergy in Systems
Course #: HBJ01WS
Date: April 12, 2018
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.
Hohmann and Barnard, Inc. 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-
AOA members available upon request.
COURSE DESCRIPTION
This course demonstrates the synergies
between various components required in
masonry construction today by detailing their
interfaces. Topics will include masonry
anchors, flashings, and air barriers.
© 2013 HOHMANN & BARNARD, INC.
OBJECTIVES
▪ Identify key components in masonry construction and how they relate to one another
▪ Discuss various product types and how they may or may not work in various installation applications
▪ Discuss how the introduction of air barrier systems has changed our ability to use certain products or installation methods
▪ Demonstrate the importance of detailing at the interface as critical to the performance of the masonry wall system
WHAT MAKES MASONRY SUSTAINABLE?
▪ Thermal Mass / Energy Efficiency
▪ Recycled Content
▪ Recyclable – Cradle to Grave
▪ Durability – Life Cycle Analysis
▪ Proximity
WHAT MAKES MASONRY VULNERABLE?
▪ Thermal Expansion within the wall
▪ Water Penetration
• Staining
• Spalling
• Degradation of the masonry units
• Degradation of structural components
RAINSCREEN PRINCIPLE
Air enters
Air exits
Open at top
Open at bottom
RAINSCREEN PRINCIPLE
PROBLEMS
▪ Expansion and Movement
• Remedied through wall reinforcing and
anchoring systems
▪ Water Penetration
• Remedied through flashings, drainage plane,
and air barrier system
Truss Reinforcement
Ladder Reinforcement
WALL REINFORCING
Standard
9 ga. Side Rods x 9 ga. Cross Rods
Extra Heavy
3/16" Side Rods x 9 ga. Cross Rods
Super Heavy Duty
3/16" Side Rods x 3/16" Cross Rods
WALL REINFORCING
Side Rod Cross Rod
INTEGRATED ANCHORING
ADJUSTABLE JOINT REINFORCEMENT
• Horizontal eyelets easily clogged with mortar
• Often relies on workmanship to assure proper
engagement of pintle within allowable limits of
eccentricity
• No guarantee that improperly installed pintle
(beyond its allowable eccentricity) will not
separate from reinforcement
• No horizontal movement
• Eyelets not welded shut
EYE-WIRE TRUSS REINFORCEMENT
LOOP-WIRE TRUSS REINFORCEMENT
• Allows in-plane vertical and horizontal movement of masonry
wythes, while restraining tension and compression.
• Loops welded shut to maintain allowable tolerance and system
integrity.
• Vertical configuration of loops not susceptible to
clogging with mortar as construction progresses.
• Foolproof. Mason can not install wire tie beyond
allowable eccentricity.
• Vertical loops have 2 ¼” adjustability. Ideal for
econo or utility bricks.
There are two ways for
moisture to infiltrate the
building envelope.
1. Diffuse flow is a
gaseous vapor that
passes through all
materials.
2. Channel flow is a more
serious concern,
resulting from breaches
in the building envelope.
Channel Flow
Diffuse Flow
DEFINING AIR BARRIERS vs. VAPOR BARRIERS
Channel Flow
Diffuse Flow
▪ An air barrier MUST resist
air leakage or channel flow at
all pressure levels through
the wall assembly.
▪ A vapor barrier MUST resist
the movement of vapor
through diffusion.
DEFINING AIR BARRIERS vs. VAPOR BARRIERS
▪ An air barrier MUST resist
air leakage or channel flow at
all pressure levels through
the wall assembly.
▪ A vapor barrier MUST resist
the movement of vapor
through diffusion.
▪ NOT ALL AIR
BARRIERS ARE
VAPOR BARRIERS Channel Flow
Diffuse Flow
DEFINING AIR BARRIERS vs. VAPOR BARRIERS
Channel Flow
Diffuse Flow
Air barriers or permeable
membranes allow the wall
to “breathe” and offer
designers more flexibility
in their placement within
the wall assembly.
The ability to make the
barrier system totally
continuous should be the
main criteria for the
location.
DEFINING AIR BARRIERS vs. VAPOR BARRIERS
Channel Flow
Diffuse Flow
Vapor barriers or
non-permeable
membranes have a
specific location within
the wall.
Vapor barriers MUST
be completely
continuous to properly
perform their function.
DEFINING AIR BARRIERS vs. VAPOR BARRIERS
Independent testing to meet
industry requirements
should be a consideration.
AIR BARRIER ASSOCIATION OF AMERICA
www.airbarrier.org
ASTM STANDARDSTESTING PROCEDURES
Areas and situations that
require detailing in an
air/vapor barrier system
include:
• Intersections of different
materials
• Expansion joints
• Elevation changes
• Inside & outside corners
• Door & window openings
DETAILING
AIR/VAPOR BARRIER INTEGRATION
The detail between an
air/vapor barrier and the
roofing system is
critical.
INSTALLATION
KEYS TO A SUCCESSFUL AIR/VAPOR BARRIER
CONTINUITY WITH THE
ROOFING SYSTEM
Does the anchoring
system protect the
integrity of the air/vapor
barrier and does the
air/vapor barrier seal
around the anchoring
system?
ANCHORING SYSTEM COMPATIBILITY
KEYS TO A SUCCESSFUL AIR/VAPOR BARRIER
Wall System Liquid Sheet
Steel/Sheathing ✔ ✔
Concrete/ICF ✔ ✔
CMU ✔ ✖
COMPARISON
LIQUID VS. SHEET MATERIALS
Anchoring for Steel Studs
Specify an anchor with rib-stiffened
pronged legs and back plate to seal
sheathing from air and moisture
infiltration. While maintaining
integrity of air barrier.
100% Protection against separation
of wire tie from anchor.(See ACI-530-02 Sec. 6.2.2.5.5.3)
Built-in screw tracks for correct
alignment of screw into stud.
3 3/8” of vertical adjustability
• Takes guesswork out of the laborers’hands.
• Allows for easy installation after
insulation is in place.
SPECIFY THE DETAILS
Built-in
screw track
Built in screw track
3⅜”
Built-in screw track
A 14 gauge anchor
capable of withstanding a
100# load in both tension
and compression without
deforming or developing play
in excess of 0.05”.
Exceeding current standards,
High Strength Anchors
are available for 150# and
200# loads.
14 gauge anchor
high strength anchor
SPECIFY THE DETAILS
Sealing mechanisms to
create a pressure seal
between anchor and
sheathing for added
protection. pressure seal
created by tape
pressure seals
created by
washers
plastic wings provide
thermal break
TIE DIRECTLY TO THE BACKUP
TRADITIONAL 3/16ӯ HOOKS
Load values that develop using
typical 3/16ӯ wire, when the
engagement is offset by more than
1¼”, the system becomes too weak
to sufficiently transfer loads.
Considering these factors
the ACI-530 Code specifies a
maximum eccentricity of 1¼”.
Unfortunately, the maximum
eccentricity of 1¼” of typical 3/16”Ø
hooks could present tolerance
problems during installation under
actual jobsite conditions.
COMPRESSED LEG HOOKS (PINTLES)
3/16ӯ wire is used because it:
• Provided suitable performance in
optimal/near-optimal conditions
• Is cost effective
• Satisfies the code requirement that the
mortar bed must be twice the diameter
of the wire (typical mortar bed 3/8”)
The 1¼” max. eccentricity limit was
addressed by specifying ¼” diam.
hooks, but this conflicts with the
code requirements for mortar
thickness to be twice the diameter of
the wire tie or hook.
An innovative solution to this
problem has, recently, been
developed.
Compressed Leg Hooks
Offering more than twice the
strength of a typical hook while still
maintaining a code-complying 3/16”
diam. to fit in a standard mortar joint.
COMPRESSED LEG HOOKS (PINTLES)
COMPRESSED LEG HOOK
STANDARD 3/16” DIAMETER HOOK (PINTLE)
COMPRESSED LEG HOOKS
COMPRESSED LEG HOOK (PINTLE)
Compressed legs are
machine-tooled to be
exactly centered between
the still rounded outer edges
Precision .020” inside radius at the bend
The modifications result in superior resistance
to lateral loads, up to 100% greater than the
industry standard, while still being fabricated
from 3/16” diameter wire.
ACI-530 Code specifies a maximum eccentricity of 1 ¼”.
The use of traditional 3/16” diameter wire hooks has been
a primary reason for this limitation.
PROBLEM AREAS
▪ Mortar Joints
▪ Weeps
▪ Flashings
▪ Protection During Construction
▪ Unique Construction
▪ Air Barrier Breach
Air Barrier Breach
Continuity is Imperative
Liquid Applied vs. Sheet
On unit faces:
▪ Surface cracks
▪ Surface imperfections
▪ High rate of moisture
absorption
(specific to brick only)
Mortar Details:
▪ Joint finishes
▪ Full head joints
WALL SURFACE DEFECTS
Full head joint in hollow concrete masonry construction is equal to the
thickness (t) of the face shell or 1.25 - 1.50 inches thick.
HEAD JOINTS: REQUIRE “FULL” JOINTS
Properly Mortared Improperly Mortared
Inadequate Head Joint
t
RECOMMENDED MORTAR JOINT FINISHES
PROFILE RAIN
RESISTANCE
GOODCONCAVE*
FAIRV-SHAPE
FAIRWEATHERED
POORFLUSH
VERY POORSTRUCK
VERY POORRAKED
*PREFERRED PROFILE
Obviously, water resistance is the main
attribute.
However, flashing should also be:
▪ Durable and resistant to damage during installation
▪ Resistant to puncturing or tearing
▪ Easily formed into desired shapes
Other Considerations:
▪ Resistance to ultraviolet light
▪ Is flashing material susceptible to corrosion in fresh mortar?
▪ Will flashing material react with adjacent materials?
(such as rigid insulation)
▪ Compatibility with materials such as sealants or adhesives
▪ The minimum expected life of the the flashing materials
should be the anticipated life of the structure
FLASHING PROPERTIES
▪ Longevity
▪ “Install-ability”
▪ Durability
▪ Extended Warranty
FLASHING QUALITIES
▪ Synthetics
▪ PVC
▪ EPDM
▪ Peel and Stick
▪ Flexible Metals
▪ Preformed Rigid
Metals
FLASHING TYPES
PVC
▪ Does not withstand chemical composition
of mortar
▪ Easily punctured on the job site
▪ Turns brittle after a
short period of time
SYNTHETIC FLASHINGS
8 mil Polyethylene Film
40 mils of Bituthene Compound
RUBBERIZED ASPHALT PEEL AND STICK
FLASHINGS
release liner
▪ Favorite among contractors
▪ Polyethylene may deteriorate in mortar
chemicals, leaving a viscous material to
support itself
▪ Extra materials required for installation
▪ Very easily punctured
▪ Susceptible to seepage through joints
PEEL AND STICK FLASHINGS
ASPHALT SEEPAGE
ASPHALT SEEPAGE
ASPHALT SEEPAGE
ELVALOYTM
▪ Has decent chemical resistance
• 15 year flashing
▪ Difficult to seam
▪ Easily punctured
EPDM
▪ User friendly - easy to bend and form directly on site.
▪ Increases the life of your structure as well as the drainage system within the wall.
FLEXIBLE METAL FLASHINGS
Traditional Copper
(Coated)
FLASHING EVOLUTION
Asphalt Free
(Self Adhesive/Flexible)
Stainless Steel Flexible
(Self Adhesive/Flexible)
• Allows for use with various air barrier systems
• Lighter, longer rolls for fewer lap joints
• Reduced opportunity for failure
clean and flexible
• Works in all temperatures
• Won’t get brittle or soften
ASPHALT-FREE FLASHINGS
• Drip Plates are recommended
by the BIA for flashings that
cannot be exposed to UV
• Meets BIA requirements
of extending ¼” beyond
face of wall forming a
drip.
• Available in stainless
steel and copper.
*Compatible with Clear Adhesive Flashings ONLY
DRIP PLATES
Flash-Adhere Strip
(with release paper) for precise and
permanent placement of flashing
Compressible filler adhered to the bottom
of drip plate acts as a bond break and
helps prevent air and moisture infiltration.
Recommended to ensure that the top edge of the
flashing will remain attached to the back-up
Sealant
Term Bar
Foam Seal
Flashing
TERMINATION BAR
Used at the top of flashing to
mechanically secure to back-up
wall.
• Type 304 Stainless Steel
• 9/32” holes spaced 8” o.c.
• Size: 1/8” x 1” x 96”
OUTSIDE CORNER
INSIDE CORNER
END DAM
STAINLESS STEEL & COPPER
FLASHING ACCESSORIES
CAVITY WALL PARAPET
SHELF ANGLE DETAIL
AT SHELF ANGLES AT SILLS
OVER OPENINGS
AT ROOF/WALL
INTERSECTIONS
UNDER COPINGS
AT WALL BASE
FLASHING LOCATIONS
AIR FLOW IN CAVITY WALL CONSTRUCTION
Decorative
CMU Veneer
CMU
Backup
MO
IST
UR
E
MOISTURE
Air, while necessary in a cavity wall, may move moisture
from one problem area and create more!
Decorative CMU Veneer
CMU Backup
Baffles at corners and intermittent
locations throughout the length of
the wall will prevent air flow from
carrying moisture through the wall.
Air, while necessary in a cavity wall, may move moisture
from one problem area and create more!
AIR FLOW IN CAVITY WALL CONSTRUCTION
MO
IST
UR
E
Promote Air Circulation,
Not Movement
Strategy works in both double wythe and single wythe
walls to eliminate suction across cavity spaces
MANAGE AIR FLOW IN MASONRY CAVITIES
Weeps at BASE of the Wall(no more than 36” apart)
Weeps at TOP of the Wall (no more than 36” apart)
Proper mortar collection, eliminates
clogged weep locations and
potential damming problems.
Weep devices
should be introduced
at the lowest
flashing elevations.
DRAINAGE DEVICES
FORMER MORTAR COLLECTION METHOD
MORTAR COLLECTION DEVICE
Must suspend mortar at
two distinct heights
“It is suggested that only superior
quality materials [flashings] be
selected, since replacement in the
event of failure will be exceedingly
expensive.”
ACCORDING TO THE B.I.A.
COMPATIBILITY
SUMMARY
▪ Masonry is an effective sustainable building material
provided it is detailed properly
▪ Brick veneer / cavity wall is really little more than a
rainscreen design
▪ Anchoring systems, flashing systems, and air barriers need
to be considered together as a wall system in order to work
correctly
▪ Air Barriers MUST be continuous to be effective
▪ While materials need to be detailed correctly, they also need
to be of quality
▪ Single-Source Responsibility allows for the widest range of
product selections with assurance of product compatibility
and installation sequencing