AWDI INSTALLATION MANUAL VOLUME 2
The New
Illustrated
Guide to
Installing
Coastal
Windows
Version 2.50
Complete Step by Step Manual
for Installation Techniques for
New Construction
in Block, Wood Frame
and Retro-Fit
Table of Contents
1
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Water Management ....................................................
5 Critical Barriers .......................................................
5
Pilot Window ............................................................
6
Recommended Installation Steps................................... 7
Coastal Installation in Block ........................................ 11
Flush Mount CMU ..................................................... 17
Fastening Windows .................................................... 18
Fastening with Clips.................................................... 19
CMU Curve-Top Installation w/Buck ............................. 20
Specifying the Proper Product ..................................... 22
Window Types and Labels............................................ 28
Types of Hurricane Protection ..................................... 30
D
Replacing Windows in Coastal Applications.................... 32
Tips for Replacing Doors in Coastal Applications ........... 41
Although all possible measures have been taken to insure the accuracy of the material presented, AWDI and the author are not liable
and do not accept any liability in case of misinterpretation of directions, misapplication, improper installation, or typographical error.
AWDI Window Fitters Guide Installing Coastal Windows
©2007-2011 Jervis & Associates - Do not reproduce without permission.
Water Management for Window and Door
Installation in New Construction
Complex Installation and Flashing Techniques are required to make sure water does not penetrate the
wall assembly either from the weather or from moisture laden vapor migrating from the warm-side of
the wall to the cold side.
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Probably the most consistent form of window failure in most climate
zones is through water penetration from faulty or incomplete
installations. Windows are one of the most difficult components of the
building enclosure to incorporate into the water management system.
If they are not, water intrusion can occur beyond the structure’s ability
to dissipate or absorb.
Leaks from windows have existed as long as windows have existed.
Water not only leaked through the windows themselves, but also around
the windows at the interface between the rough opening and the window
frame. In many older solid masonry buildings this was not a problem
due to the capacity of the construction to absorb moisture and dry out
under more favorable conditions.
As the construction industry changed, materials and assemblies used
had less of a capacity to manage moisture. The absorption capacity and
the drying potential of assemblies were significantly reduced. This led to
serious problems directly related to window leakage.
Risks associated with window leaks are affected by various characteristics — from the climate in which the window is installed, to the materials
used, to the skill and attitude of the person doing the installation.
Understanding these factors including the limitations and critical
aspects of the installation is important in deciding the appropriate
installation technique to use.
AWDI recommendations and standards rely heavily on all published
work, including ASTM E2112, AWDI 1.3 (Revised), and field experience
though years of certification, testing, and service work. Building Sciences
Corporation in Westford, MA has also done extensive research on rain
water management for windows and doors, and their observations are
included in the text and illustrations used in this manual.
D
These descriptions and instructions deal with both the need to properly
flash the installation and the need to maintain vapor barrier continuity.
Flashing deals with water and moisture intrusion through weather
related causes, and Vapor Barrier relates primarily to the migration of
moisture laden warm air towards drier cold air and the resulting condensation that can introduce moisture and water into the installation cavity.
Installation has historically been the least respected of the disciplines in
construction and is usually treated as a cost to be minimized – attracting
low skilled workers, or a split in the trades doing the work eliminating
consistency and continuity of care and responsibility. The skills and care
needed to be successful in window and door installation require attention and should not be considered lightly.
AWDI Installation Manual Volume 2- Coastal Windows
1
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
There are two basic window installation
strategies: a barrier approach or a drained
approach.
The barrier approach works under the preconception that
the installation will keep all the water out and is the
approach traditionally used by much of the industry. In
this approach, the window is sealed on all four sides in an
attempt to create a perfect barrier against water infiltration.
Experience has shown that most window installations do
not have the ability to perform as a perfect barrier for the
life of the window installation.
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In addition, the ability to actually create the barrier is
undermined by damage to or flaws in the frame of the
window and door product either from manufacturer or
on-site damage or both. Due to this, barrier systems,
while a form of water management, are not generally
recommended and should only be considered for use in
certain assemblies such as mass wall assemblies.
Drained systems work under the concession that some water will leak through the window at some point in time, and
provisions are to be made to direct the water back out to the exterior. This approach has been shown to be an effective
method of water management, though care must still be taken in the design and application of the system.
AWDI recommends the drainage system approach.
Most standards and practices for window and door installation focus on
barrier techniques. This is due primarily to two reasons. First, theory
and lab observations allow barrier techniques to work as designed.
This is not true in the field. Second, window manufacturers are primarily
concerned (understandably) that their products do not leak, and little
concern for the performance of the wall.
While the construction of the wall and the application of the various
wraps, barriers, and flashings on the wall are the responsibilities of
others, the AWDI trained installer can mount the new window and door
into the opening, and make sure that any water that enters is directed
away from the interior and is given a path to drain properly to the
exterior.
And, the AWDI trained installer can take care to maintain vapor barrier
continuity to be sure any migration of moisture is out of the cavity
between the window/door and the opening to a place where it can
drain, dry or be absorbed to eliminate chance of rot, mold or other
damage in the wall structure.
D
The AWDI drainage method, when its techniques and materials are
applied to the window or door opening, assure that the installation will
not leak, and that damage to the materials within the opening cavity
are mitigated. It is the best method over the long haul, and superior to
the barrier method in today’s energy efficient constructions.
The proper approach to installation in replacement applications is
addressed in detail in the AWDI Illustrated Guide to Installing
replacement Windows. The material contained in this guide will
deal with New Construction Applications exclusively.
AWDI Installation Manual Volume 2- Coastal Windows
2
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
The Importance of the Nailing Fin
SEALING THE INTERIOR/EXTERIOR
AGAINST AIR AND MOISTURE
Most residential windows on the market are designed with
a nailing fin to help with the installation of the window. The
fin is intended to make consistently lining up the window in
the same location in the rough opening easier. The fin,
however, is often not structural and proper shimming and
blocking of the window is required. This nailing fin has
some advantages and some disadvantages associated with
it. While it does make the installation easier, the water
management strategies must be carefully considered.
Exterior Molding
Weather Sealed
NEW CONSTRUCTION
FIN APPLICATION
Interior
Caulk
The nailing fin should be considered a part of the drainage
plane of the wall. It does work very effectively, as long as
the fin is continuous around the entire window perimeter
and integrity of the fin is maintained.
Insulation
Air Seal Using Sealant,
Backer Rod, and
Contractor's Tape
Backer Rod
Sealant
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The nailing fin is usually a thin PVC or metal fin that is
part of the frame extrusion and generally not very strong.
These fins can be damaged, bent or broken during the
delivery or installation of the window system into the wall
assembly, or may not be continuous around the window
depending on the assembly at the corner joints of the
frame. Damaged and broken nailing fins can lead to fundamental failures in the integrity of the drainage plane of the
wall assembly as membrane tapes and building
papers/housewraps no longer have adequate area of material to adhere to or cover over the fin.
Contractor's Tape
Most housewraps are not flashings. In fact, housewraps are
vapor porous and are no better than air barriers. Use of a
housewrap to create shingle-lapped flashing is inadequate
and should not be relied on to work.
In addition, adhesive-backed flashing materials need to be
fastened to the exterior wallboard (exteriorRplywood or oriented strand board). Fastening to the housewrap will only
create a patch for the water to go under the flashing and
into the interior.
As long as the nailing fin is continuous and undamaged
it can be effectively integrated into the moisture
management of the wall assembly. Self-adhered
membranes are often used to integrate the nailing fin
into the drainage plane of the water management system
of the wall assembly. Adhesive-backed flashing materials
like Grace Vycor are used to seal to the nailing fin in a
shingle lap fashion to prevent reverse laps that can create
paths for water intrusion.
Pan Flashing is Required
The installation of a pan flashing at the sill of the rough
opening is critical to the design of drained window
installations to protect the framing of the rough opening
from moisture damage and to help direct any water back
out to the exterior. Sill Pans can be can be created out of
numerous materials, such as membrane flashings, and
metal, but this requires additional skills and care that often
lead to problems because of
the irregularities of the
framed opening. AWDI recommends use of a preformed sill pan, such as
Jam-Sill.
D
Drip
Cap
AWDI Installation Manual Volume 2- Coastal Windows
Ideally, the pan flashing
would be sloped to the
exterior. This can be
achieved through the use
of a section of board siding
laid flat under the pan
flashing at best, or smart
use of the shims used to
level the sill pan between
the jambs.
Flashing
Over
Nailing
3
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Vapor Barrier Continuity
The function of a vapor barrier is to retard migration of
water vapor. Where it is located in an assembly and its
permeability is a function of climate, the characteristics of
the materials that comprise the assembly and the interior
conditions. Vapor barriers are not typically intended to
retard migration of air. That is the function of air barriers.
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The fundamental principle of water control in the vapor
form is to keep it out and to let it out if it gets in. This
becomes complicated because the barrier method of
window installation used in the past meant to keep water
vapor out was found to trap water vapor in. This can be a
real problem if the assemblies start out wet because of rain
or the use of wet materials, but can be the principle cause
of mold, rot and other decay in the cavity between the
window or door and the rough opening. Moisture can also
lessen the insulation value of fiberglass or other insulation
materials placed in the wall.
VAPOR
BARRIER
CONTINUITY
The condition of the rough opening can affect the performance of the drainage of the pan flashing. The exterior
sheathing must not extend higher than the sill framing.
In this situation, even with a perfectly installed pan flashing, the drainage of the system will be compromised.
VAPOR BARRIERS ARE USUALLY
VIOLATED WHEN WINDOWS ARE
INSTALLED
Moisture-laden Air is allowed
into the Cavity between the
Rough Opening Framing
and the Window Frame.
The preformed plastic sections usually have integrated
back-dams. With these products the jambs and sill joint
between the two pieces must still be sealed with membrane
to prevent water intrusion below the pan flashing. The
procedures are simple, but important. If done well, no
water will back up into the interior.
Allowing Moisture into the
Cavity can cause rot or other
degradation of the installation
and can lower the thermal
performance of the window unit.
Accommodating Two Drainage Constructions
There are two basic drainage constructions. While the
details are not germane to this manual, it is important to
understand the differences as one is more often used in
wood frame construction and the other in CBS or other
masonry applications.
Moisture-laden Air
In wood frame, penetrating water is directed to a water
resistant barrier (WRB) and directed downward and out
of the building at the base of the wall. The WRB is
traditional building paper. If house wrap is used, then
the exterior sheathing must be water resistant.
It becomes even more complicated because of climate. In
general, water vapor moves from the warm side of building
assemblies to the cold side. This is why insulation battes
have building paper type surfaces on one side (used to
staple to the studs). Determining the warm side/cold side
needs different strategies for different climates, and
differences between summer and winter.
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In masonry and masonry block construction, the intruding
water is absorbed in a non-water sensitive material,
re-distributed and released to the outside and the inside
in a controlled way. If covered with stucco, the masonry
will need a bond-breaking building paper and a WRB to
allow the moisture to pass between them. If it is a brick
veneer, then there will be space between the brick and the
exterior wall.
For the purposes of window and door installation, AWDI
proper installation will maintain continuity in the vapor
barrier with regard to the window or door opening making
sure any potential moisture migrating into the cavity
between the window and door and the rough opening is
not trapped, will not condense, and is free to dissipate
In either case, the window or door is mounted to a wood
before it can cause damage. It is an extra step not usually
surround, and the instructions to follow make sure all
water is directed away from the cavity and into the drainage taken by window and installers, but necessary for proper
and effective and long lasting installations.
system regardless of the drainage construction.
AWDI Installation Manual Volume 2- Coastal Windows
4
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Step 4:
Step 6:
Cut the proper size
Weep Screen and insert
it under the front lip of
the installed sill pan, as
shown, and staple it to
the sheathing.
A drip cap should be
used across the header
of the of the installed
window/door. Often,
“J-Channel”, when
used with siding is
thought to be a drip
cap.
Place a bead of sealant
(Sika or equal) on the
back of the nailing
fin/flange of the
window or door. You
can also apply the bead
of sealant to the flashing directly.
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Do not rely on the work
of others . Bend a cap
or used the supplied
cap and install on top
of the window/door
using sealant.
Do not place a continuous bead along the sill
of the opening or the
window or door.
Drip cap
Step 5:
Place window/door unit
into opening, pressing
the nailing flange/fin
against the flashed
opening to make a firm
contact with the
sealant.
Once the drip cap is
installed and the window is seated in the
opening, plumb and
square, the top layer of
the adhesive-backed
flashing can be applied.
D
The surface flashing is
applied to the jamb
sides first, overlapping
the sill pan, weep
screen and sill flashing
assembly.
The header flashing is
applied over the top
fin/flange of the window and overlaps the
jamb flashing.
The bottom is kept free
to allow drainage of any
water penetration into
the drainage plane.
Step 5
AWDI Installation Manual Volume 2- Coastal Windows
Step 6
Step 7:
Simplex Cap Nails OVER fin allows
frame to move better than nails
through mounting slots
Using a framing square,
plumb and square the
window/door carefully.
Remove operable sash
if necessary. Shim with
plastic, flat, stackable
shims. Never use
tapered wood shims.
Using fasteners, anchor
window through frame
into the jambs on both
sides. Use Simplex
Cap Nails on Header.
Lightly apply mounting
nails through slots in
fin if provided. Do not
nail tightly.
g
Window
frame
Step 4
9
Step 7
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Alternate 2 and 3:
If the house wrap has been moved aside, it can
now be un-taped and placed over the second
layer of self-adhesive flashing to complete the
installation.
Again, take care to leave the bottom free for
drainage into the drainage plane.
Alternate 2
Alternate 3
Vapor Barrier Continuity:
As detailed, the continuity of the Vapor Barrier
of the wall assembly must be maintained.
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ASHRAE identifies different climate areas
that create different dynamics to water vapor
migration.
AWDI recommends that the cavity between the
window/door unit and the rough opening be
sealed to prevent this migration of moisture
laden air from the warm side of the wall to the
cold side of the wall which can cause condensation and trapped water.
This condensed water, if it can’t dry or escape
can cause mold, rot, and decay and lessen the
ability of insulation materials placed in the
cavity to perform.
Details of maintaining vapor barrier continuity
can vary by climate. However, under no circumstances should a water resistant barrier be
placed on both sides of any wall, as a double
vapor barrier will cause many problems long
after construction is completed and all window
and door products have been installed.
The Sequence is Important.
To Be Sure Adhesive Backed Flashing
Adheres Directly to the Sheathing
on All Sides, Peel away any Building Wrap
D
The process is called shingling, and it describes
the overlapping of each layer when creating a
water-tight window and door installation. There
should be no tears in the flashing that aren’t
taped, mounting hardware holes that are not
filled with sealant, and all materials must
overlap in a manner to direct the water away
from the interior, away from the window, and
into the drainage system in the wall.
Seal Corners and Be
Sure to Install Drip Cap
Vycor on
Sill Up 4”
Vycor on Sill
Roofing Nail
Head to Hold
Sill Pan
Barrier techniques do not work because of
flaws in the materials and in the labor, and
because they materials degrade over time, and
eventually fail long before the window/door
unit and the house construction.
AWDI Installation Manual Volume 2- Coastal Windows
Vycor to Stick
to Sheathing
Weep Screen
Stapled
over Vycor
the placed
Under Sill Pan
Sill Pan
over Vycor
Keep Weep Holes Free
10
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Coastal Installation with Installed Buck
Coastal
Installation
Sealant
Stucco finished homes
are prevalent in coastal
areas of the US and with
the advent of Hurricane
Code Standards in
Florida and elsewhere,
installation of products
for these areas require
different details, techniques and procedures.
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Fasten
Into Block
The current Florida Building Code deals with installation
issues as they relate to the ability of the window and door
product to sustain wind driven debris. This has caused the
mounting hardware and procedures to be change dover the
last couple of years, and the glazing requirements have
risen to where impact glass or shutters are necessary for all
products.
Countersink Fastener
and fill with sealant
The Florida Building Code with respect to fenestration has
been adopted in total or in part for all costal regions subject to high winds. These mounting procedures, fastener
requirements and glazing standards will be expected with
regard to the products installed. The techniques for proper
installation are now being addressed by FMA and ASTM to
create a procedure where windows and doors can be
installed to minimize water intrusion as much of the damage from the hurricanes of the last couple of years was
from water, not from wind.
The instructions and recommendations included in this
AWDI Manual follow much of the work done by FMA and
ASTM with some exceptions. These exceptions will be
noted.
Typical Aluminum Window in
Stucco Veneered Block or Frame Wall
There are two types of drainage walls: membrane drainage
walls and cavity drainage walls. A system utilizing stucco
is an example of a membrane drainage wall, whereas a
system using masonry veneer is usually designed as a cavity drainage wall. In drainage walls, evaporation may also
play a role in moisture dissipation, but is a comparatively
slower process subject to weather conditions.
Stucco Finish
A building system utilizing stucco as a wall cladding is
generically known as a drainage wall, a wall system in
which the outermost material provides a substantial barrier
to water and a secondary material, typically a weather
resistive barrier (WRB), provides a backup barrier to water
that may penetrate the cladding. Penetrating water is
intended to flow by gravity to the exterior outside of the
WRB and is prevented from reaching water-sensitive
materials.
As a material, stucco can provide a high resistance to
passage of liquid water if properly formulated and cured,
but it is not waterproof. Neither is it, as thought by many,
porous. In fact, when liquid water penetrates stucco
cladding on a building, it almost always does so not
through the field of the stucco but through breaches at
cracks, control joints, perimeters of openings such as
doors and windows and joints with abutting materials.
In a properly designed stucco clad wall, water from these
breaches is expected to penetrate no further than the
D
Until the final ASTM spec is written, submitted, and
approved, the steps contained in this manual should be
considered best practices, because they are based on
sound water management principles for the housing wall
designs used for stucco finished block and stucco finished
wood frame. They are the result of field experience, and
field study by AWDI, the Window Fitters Guild, and
Building Science Corporation.
AWDI Installation Manual Volume 2- Coastal Windows
11
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Weep Screeds are Recommended
The second component of the systems design requirements
is a weep screed at the bottom of the wall and at all soffits.
Wherever the vertical wall terminates and/or changes
direction, water that may collect
behind the stucco veneer needs
to be able to drain out. This negatively effects window and door
openings where the window unit
is recessed from the plane of the
wall. If no weep screed is
installed, the water will be
directed to the header of the
window unit, and this is often
the case. Therefore, water needs
to be directed away from the
window/door header and back
into the drainage plane to be
able to escape from the behind
the veneer and not penetrate
into the interior of the building.
WRB and exit the wall base at a weep screed or dissipate
through evaporation. There are limits, however, to the
volume of water a stucco clad wall system can successfully
handle.
Stucco can be applied over block (typical CBS construction)
or over wood frame (often used for the upper story of
residential homes). In CBS construction, the block is the
Water-Resistant-Barrier (WRB), and in wood frame
applications, stucco is placed over a WRB which is a
membrane such as water-resistant building paper.
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It is not the province of this manual to discuss various
construction methods. However, the success of a window
or door installation is dependent on the successful
handling of the water that will penetrate the stucco.
These instructions are dependent on certain principles
to accomplish just that.
The role of Concrete Block
The concrete block used in residential housing, when
covered with stucco, becomes the water resistant barrier.
What that means is that it retards the passage of the water
into the interior of the home. Many mistake that to mean,
no water should be absorbed into the block, when in reality, the successful performance of the CBS wall depends on
a certain amount of absorption to handle the inevitable
water penetration of the stucco in severe weather.
Proper Sill Pan
The third component of an effective stucco wall, is the
drainage of the sill of
the window or door unit.
As the illustrations
show, improper sill
shape, improper sill
slope, and improper
Drains to
drainage path for the sill
Inside
will cause problems and
not allow the stucco
wall to perform as it was
intended.
Two ways water that gets behind stucco is handled
Drained Assembly
Mass Assembly
The last consideration is
the creation of the window or door opening.
Too often it is out
Drains to
of square, improperly
Outside
sized, improperly
bucked, and improperly
prepared to accept the
window
or door. Added to this is the reliance on other trades to
prepare the opening before the window installer technician
arrives to fit the product.
D
When stucco claddings leak, the penetrating water is
traditionally managed in two fundamental ways. The first is
direction to a water resistant barrier such as in a “drained
assembly where the water exits the wall downward, and the
second is a “mass assembly’ where the eater is absorbed in
non-water sensitive material and released to the interior
and exterior in a controlled way during “drying” periods.
Concrete block serves this purpose well and it is expected
to do so in CBS construction. However, it is also expected
that the rate of drying will not be exceeded by water
collection, so fenestration installation must limit possibility
of excess water getting inside the cavity.
AWDI Installation Manual Volume 2- Coastal Windows
These instructions will assume that the window fitter has
examined the opening and has assured that the rough sill
is proper, and that the dimensions are accurate within
1/8” in plumb, square and level. No fenestration product
should be installed in any other opening. In addition, the
window fitter should fabricate and install the wood bucks,
and the sill pan or equivalent(s) and seal them adequately
before mounting the new window or door.
Credits: Photos and Artwork courtesy of Building Science
Corporation; TM Windows and Doors; Builder Magazine, December
2005; and AWDI Standards, version 1.3.
12
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Coastal CMU Installation with Flush 2x8 Buck
2 x 8 Step 1:
2 x 8 Step 3:
To flush mount a
finned window use
2”x8” pressure-treated
buck material fastened
to the block with code
required fasteners
properly embedded into
the block.
Using flexible,
adhesive-backed
flashing, create a sillpan by applying the
flashing along the sill
and up the sides
approximately 6 inches.
Use sealant on the
block to seal the buck
against the block when
installed. Seal all four
corner joints.
Precast
Lintel
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Poured
Sill
2x8 Buck
on All
Sides
Exterior
Exterior
2 x 8 Step 2:
2 x 8 Step 4:
As with recessed
mounting, treat the
masonry opening with a
CMU sealer for the
purpose of sealing the
CMU window cavity
from absorbing liquid
water.
Once the window is
mounted, flexible
adhesive-backed
flashing and wire lathe
as needed to be sure
the entire exterior
perimeter is well sealed
to shed surface water.
D
Be sure to cover the
buck, and the block inside and out to a distance of approximately
9” out from the opening
in all directions.
Exterior
AWDI Installation Manual Volume 2- Coastal Windows
Exterior
17
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Fastening Windows
Three Window Frames
Three ways to Mount a Flush Window
There are different window types, and each has a variety of
ways it can be secured in the opening, approved for Coastal
areas in the US.
EXTERIOR
SHEATHING
FIN
OPENING
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Fin Frame
Windows with Fins usually are
mounted using the fin, and
securing the fasteners through
the fin in to the wall sheathing.
Occasionally, where required to
meet load design, mounting
screws can be applied through
the frame into the structure.
Flange Frame (Unequal leg)
Flange windows are not be confused with Fin windows. Flanged
WOOD BUCK
FLANGE
windows have a protrusion of
about 1/2 inch on all four sides
and can be called “unequal leg”
windows. The flange is used to
set the window in place against
the opening or an installed buck.
The flange allows the installation
to be sealed with the flange acting as an overlap to prevent
water penetration into the opening.
Where the shim or buck is less than 1-1/2 inches, window
and door assemblies shall be anchored through the jamb,
or jamb clip, and anchors shall be embedded directly into
the masonry, concrete or other substantial substrate.
The flanged window is mounting to the opening using a
clip system and/or mounting through the frame into the
structure as required.
Flush Frame (Box Frame)
Flush Mount windows or boxframe as they are also called,
contain no fin or flange and
mount in the opening using clips
and/or mounting through the
window frame into the structure.
Where the shim or buck 1-1/2 inches or greater, the buck
is securely fastened to the masonry,concrete or other substantial substrate and the buck extends beyond the inner
face of the window or door frame, window and door
assemblies shall be anchored through the jamb, or jamb
clip, into the secured buck.
ROUGH OPENING
D
Flush or box mount windows
will need backer rod and sealant and/or snap trim to
adequately create the barrier to moisture and water
intrusion or migration into the opening.
Where the framing material is wood or other approved
framing material, window and door assemblies shall be
anchored through the jamb, or through the jamb clip.
AWDI Installation Manual Volume 2- Coastal Windows
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Mounting with Clips
Installation Clips Installation Clips are used on both wood windows and
uPVC window frames where the clips lock into the frame,
and then the clips are mounted to the buck system or
directly into the block with code compliant mounting
hardware.
D
Follow the instructions for the proper window load
resistance and as shown by the manufacturer. A sill pan
should still be used, or a tapered sill be incorporated into
the opening. Snap-trim can be used to seal to the outside.
AWDI Installation Manual Volume 2- Coastal Windows
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.
CMU Curved-Top Installation with Buck
Installing Curved Windows in CMU Openings is a difficult
procedure because the concrete block, or even poured
concrete lintel is difficult to make perfectly smooth and
round, and join the rough opening jambs seamlessly.
The applied buck is made from a flat stock - either 3/4”
thick or 1-1/2” thick and this stock is not easily bent
to a shape. If it can’t be bent well, the circular window
cannot easily mount weather tight and water and moisture
penetration resistance like the rectangular units can be.
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Fabricating the opening to accept a curved window
requires on of two approaches:
1. Kerfing the stock (as shown) by slicing a
multitude of grooves in the surface
2. Utilizing a free foam, cellular pvc stock
which can be bent to a radius in a smooth fashion.
Accommodating the
Curved Window
The Opening must be level, plumb and square, and the
mortar properly applied to allow no voids, cracks or
clumps that might allow water infiltration.
A proper sill must be accommodated either with a pre-cast
sill, or an applied buck with a sill pan installed as shown.
Note: Florida Building Code Requires that
products tested for wind and debris - especially for hurricane
and high wind zones - be installed as they were tested.
Precast
Lintel
This can mean anything other than a wood buck sill may
void hurricane and wind approvals.
D
Poured
Sill
AWDI Installation Manual Volume 2- Coastal Windows
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Once a curved masonry
header member is created,
the installation steps are
basically the same as for
rectangular windows
Cellular PVC “arc’d”
Header buck
Free Foam Cellular
pvc can be arched
smoothly to make the
best curved buck
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Smoothly Arc’d
Cellular PVC
Header Buck
Seal Joint
Kerfing - cutting multi
grooves in wood to
facilitate bending
Alternate wood frame method
Where poured header, with curved inner surface, is not
provided, a wooden section is built within the rectangular
opening, having a curved surface to which the window
buck is mounted. This method is often used to
match CMU walls with wood frame walls.
Wood Constructed
Header Opening
with arc’d wood
blocks
Kerfed Curved
“Buck”
Because bending a wood buck is difficult, this method is
better suited to flush mount, finned windows.
D
Blocks are fastened
in a rough arc to
which the kerfed
buck is to be nailed
It is difficult to
kerf wood which
often creates a poor
header buck
AWDI Installation Manual Volume 2- Coastal Windows
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Specifying the Proper Product
Five steps to Design, Specify and
Install storm-resistant windows.
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1. Consider Wind Zone and Exposure
Building codes contain maps detailing
basic wind speeds that can be expected
in any area of the United States over a
50-year mean recurrence interval.
These are the starting point for
calculating an exterior opening's
exposure to pressures from high winds.
In addition to design wind speed, a
building is rated with an exposure
classification which indicates the level
of sheltering around the building.
Exposure classifications range from
A (city center with tall buildings
surrounding) to D (flat, unobstructed
area exposed to wind flowing over
open water).
Because vast expanses of open land
or water allow unobstructed wind
movement, the best practice is to site
windows on walls where natural
landscape features, like tree buffers or
dunes, protect them from direct wind.
If tree buffers are created, plantings
should be located farther away from
the structure than their expected
height at maturity.
Obstructions on a building's façade,
like bay windows and cantilevered
decks, create vortexes for wind
movement. Where these architectural features are present,
builders should ensure that cladding and structural
attachments have been properly designed and attached.
D
2. Identify Products That Work for the Region
A. Performance Classification
The building codes require all windows to meet wind-driven
rain conditions under the testing standard "Voluntary
Specifications for Aluminum, Vinyl (PVC), and Wood
Windows and Glass Doors," AAMA/NWWDA 101/I.S.2.
The standard establishes five classes of windows based on
the (wind) design pressure (DP) that the window was tested
to, as detailed in the specifications. A DP of 40 is equal to a
155-mph wind. You can determine necessary design
pressures from the Table of Equivalent Wind Velocities.
B. Impact Resistance
In addition to the force of wind and wind-driven rain,
homes are often struck by airborne debris from compromised structures and landscaping during storms.
Therefore, building codes also require that window and
AWDI Installation Manual Volume 2- Coastal Windows
door products installed in homes in areas where winds
exceed 110 miles per hour meet tests for impact resistance.
The tests mimic the window, door, curtain wall, or protective covering being struck by gravel traveling at 80 feet per
second (called small missiles) or a 2x4 stud traveling at 50
feet per second (called a large missile) and undergoing
repeated strikes. The Florida Building Code (FBC) requires
that windows in high wind zones located within 30 feet of
the ground meet the large missile test criteria and those
higher than 30 feet from ground level meet the small
missile test criteria.
C. Energy Efficiency
In addition to resistance to high wind, windows should be
selected for energy efficiency and function. The easiest
way to select the most energy-efficient window for a climate
is to choose one bearing the ENERGY STAR© logo. In the
absence of that designation, windows can be selected based
on their thermal and other properties. The National
Fenestration Rating Council (NFRC) operates a voluntary
labeling program which provides efficiency information to
consumers.
22
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Ten years after Hurricane Andrew caused an estimated $26
billion in property damage that displaced 250,000 people,
Florida became the first state in the nation to create building codes that addressed the extreme wind conditions experienced during tropical storms in coastal regions. The
Florida Building Code (FBC) requires that buildings be
designed to withstand design pressures (DP) that are a
function of wind zones mapped for mainland Florida and
the height and exposure of the structure.
The International Residential Codes (IRC) of 2000 and 2003
and some Gulf Coast states' adoption of the IRC, as well as
the pending FBC addition of additional wind zones in the
Florida Panhandle, will place all coastal states under similar wind design prescription.
Per the FBC,
protection of
exterior windows
and glass doors
from windborne
debris in buildings located in
hurricane-prone
regions is
required in
Miami-Dade
and Broward
Counties.
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3. Size Windows for Egress
Bedrooms and habitable sub-grade basements require
windows sized for escape or entry (by rescue personnel) in
the event of
a fire. The
International
Residential
Code (IRC)
requires a
minimum
opening
width of 20
inches with
5.7-sqft
minimum
free area at
a sill no higher than 44
inches from
the floor.
Depending on the manufacturer, this requirement can usually be met with a 26x48 or larger double-hung unit. It is
important to consider that inoperable hurricane shutters,
like homemade plywood coverings that are applied from the
exterior, will impede quick exit or entry when in place, as
will shutters that require power to operate if the power
source goes out during a storm.
4. Follow Manufacturer's Installation Instructions
Ultimately the day-to-day and disaster mitigating performance of window and door components depends on competent installation. Manufacturers provide detailed installation instructions. This and trade contractor quality assurance programs assure builders that the units have been
professionally installed.
5. Consider Installing Shutters
Shutters or other temporary coverings can provide impact
resistance to windows and other
openings. Miami-Dade County
has a searchable database of
products that comply with FBC.
D
Code Considerations
The International Residential
Code (IRC) requires exterior
windows and doors to be
designed to resist the design
wind loads specified in Table
R301.2(2) adjusted for height
and exposure per Table
R301.2(3) and that they be
tested and labeled.
Labels must include manufacturer, performance characteristics, approved inspection agency, and compliance with the
requirements of either AAMA/NWWDA 101/I.S.2, or the
new version, AAMA/WDMA 101/I.S.2/NAFS, Voluntary
Specifications for Aluminum, Vinyl (PVC) and Wood
Windows and Glass Doors.
AWDI Installation Manual Volume 2- Coastal Windows
A Miami-Dade County Notice of Acceptance (NOA) for
impact-resistant products is one way to ensure that a window has been tested and meets all the requirements for
hurricane protection in the highest wind velocity zones. The
Florida Building Commission recognizes Miami-Dade NOAs
as approved products.
Impact-Resistant Doors
Impact-resistant doors have been tested and labeled for
their ability to withstand wind-born projectiles. They often
include impact resistant glass, although the method of
attachment also affects a door's impact-resistance. Make
sure to look for appropriate labels designating the tested
characteristics of an impact-resistant door.
Sliding glass doors are larger and more vulnerable to wind
and debris than most doors and windows. Use impactresistant glazing where possible, or at the very least install
hurricane shutters.
Reinforced Garage Doors
or Single-Car Openings
Often, due to its large size and the relatively weak materials
of its construction and hardware, the weakest opening
point in a home is a garage door. Garage doors can now be
constructed, tested, and rated for impact and wind resistance. The marginal cost of a rated garage door is only
$200 to $300 over a door without wind-resistant features.
A retrofit kit to strengthen an existing two-car garage door
will cost about $300. A kit usually consists of a vertical
post that is placed between the roof and the concrete floor,
although other systems also exist.
24
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Such tinted glass shall be installed on all windows and
glass doors of a single or multi-story structure within
line-of-sight of the beach.
The standards for fenestration products in existing
beachfront construction shall reduce or eliminate the
negative effects of interior light emanating from them.
Several suggestions include applying window tint or film
that meets the criteria established for tinted glass in new
construction, rearranging lamps and other moveable light
sources away from windows, or use of window treatments
(e.g. blinds, curtains, shutters) to block light
Wind Pressure
The wind that blows at a window or door, and the wind
that blows past a window or door creates a pressure. The
pressure created by the wind blowing at the window or
door is specified by a positive DP (Design Pressure) number.
The amount of pressure created by wind that blows past or
by a window or door is specified by a negative DP number.
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Design Pressure ratings
Homes in any of the wind-borne debris regions must also
have windows and doors with specific design pressure (DP)
ratings, which include positive and negative numbers.
Positive corresponds to pressure created by wind blowing at
Specifying Windows
a window and door. Negative represents vacuum pressure
Windows and doors are usually selected for their structural on the inner side of the window or door. DP rating
performance characteristics based on local or state building requirements are site specific, so consult the architect or
code requirements. The primary consideration is structural contractor for the ratings needed for your area.
integrity of the window or door, to keep it intact and preWind Zones
vent the pressure of high-velocity wind from entering the
ZONE 1 Areas within 1 mile of the mean high tide line
building and causing catastrophic structural damage.
with winds 110 mph and up to 120 mph
In tropical storms and hurricane wind-driven rain condiZONE 2 Areas more than 1 mile from the mean high tide
tions the product selected to meet the state and local code
line with winds 120 mph up to 130 mph
requirements may still experience water leakage because
ZONE 3 Areas with winds 130 mph and up to 140 mph;
these extraordinary conditions exceed the rated/code
or 120 mph and up to 140 mph within 1 mile of the mean
requirements for water penetration.
tide line
ZONE 4 All areas with winds in excess of 140 mph (highTesting Requirements
velocity
wind zones)
To meet building codes, windows and doors within
hurricane areas must pass certain requirements, such
as impact resistance and wind pressure tests. These
requirements vary by area, so consult your builder or
contractor for specific criteria. Different testing results are
required in each of the four wind-borne debris regions.
Confirming Qualified and Tested Products
On the Internet: http://www.miamidade.gov/buildingcode/pcsearch_app.asp
Zone 3
Zone 1
110 mph - 120 mph winds
130 mph - 140 mph winds
Zone 2
120 mph - 130 mph winds
Zone 3
120 mph - 140 mph winds
1 Mile from Mean
High Tide Line
Zone 4
D
Above 140 mph winds
Mean High Tide Line
WIND BORNE DEBRIS REQUIREMENTS
Wind-borne debris region Impact resistance requirement Wind pressure requirements
ZONES 1&2
ZONE 3
ZONE 4*
Must withstand a 4-foot-long 2x4 at 40' per second (27 mph) Hurricane loads up to 9,000 wind cycles
Must withstand an 8-foot-long 2x4 at 50' per second (34 mph) Hurricane loads up to 9,000 wind cycles
Must withstand an 8-foot-long 2x4 at 50' per second (34 mph) Hurricane loads up to 9,000 wind cycles
*Impact resistance testing for Zone 4 may also include multiple hits per test unit and mullions.
AWDI Installation Manual Volume 2- Coastal Windows
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.
on the beach (as shown in our diagrams) have the
toughest requirements because they bear the brunt
of any storm.
The storm resistant window requirement headed
north when the new International Residential Code
began mandating them all the way up the eastern
seaboard, but not all areas need the same windows
as South Florida.
Homes a few miles inland generally have a lower
design pressure, because the code assumes that
surrounding structures will provide some shelter
from the wind.
Windows must meet a “design pressure” requirement
that’s determined by a number of factors, the most
important of which is the geographic wind speed zone
the house is in.
Downtown urban areas might get an additional break
because of the shelter provided by tall buildings.
The heights of the structure and the surrounding
structures also come into play, as does the size of the
opening. Buildings that are critical to the community,
such as fire stations and hospitals, have tougher
requirements than other structures in a particular
zone. Local codes will usually be specific. Many
regions use Dade-County as default, for example.
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As we have discussed, windows in high wind areas
need to be able to stand airborne debris and window
driven rain. While the toughest conditions and
therefore the toughest standards are in South
Florida, the IRC has defined high wind areas all up
and down the East Coast as the map below shows.
Design pressure is the determining factor, and the
wind zones dictate that pressure. As we have learned
from recent storms, all damaging hurricanes are not
necessarily limited to Florida. Coastal installations
are applicable to all coastal regions.
Design pressure calculations can get extremely
complex. Most manufacturers are happy to provide
help in determining qualifications of their products
for certain applications. However, you should
confirm the product’s performance ratings with the
local building department if you are charged with
While the geographic wind speed map is the starting
place, other variables come into play. Structures right specification and/or ordering.
Coastal
Wind Load
Considerations
D
The Map Shows the Wind
Load Design considerations for
States and Counties subject to
the Coastal Weather that
brings higher windows and
moisture from storms.
Source: IRC
AWDI Installation Manual Volume 2- Coastal Windows
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Window Types and Labels
Everything you need to know is
on the window label
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Permanent Window Labels
The permanent labels allows 1) manufacturer
and product information and 2) the performance rating to be tracked for the life of the
fenestration product. These labels are placed
on certified products and are usually affixed
on and interior part of the product between
the frame and sash or the frame and door.
The label should be visible after the products
have been installed. Three types of permanent
labels can be found on fenestration: AAMA,
NWWDA or NAMI/AAMA Labels.
The American Architectural Manufacturers
Association (AAMA) certification label serves
the purpose of identifying fenestration
products that conform within specific
tolerances. The design and fabrication of
fenestration models are tested in accordance
with the procedures established by the AAMA
Certification program and have met the
requirements of the specification printed on
the label. The fenestration products include
windows, doors and skylights manufactured
from aluminum, vinyl, fiberglass, composites
and a combination of these materials with
wood.
AAMA certification is third party certification.
The third party is and outside organization not
under the control of influence of AAMA. This third party is
responsible for the validation and administrative functions
for the program.
The most important function of certification is the
assurance that products bearing the label do, in fact,
meet the requirements of the standard. AAMA rates the
window's ability to withstand wind loads, water resistance
and the air infiltration rate.
AAMA accredits independent third party laboratories that
test the performance of the manufacturer's products.
The higher the grade, the better the window's performance.
PRIME & REPLACEMENT LABEL (AWS & THERMAL)
12455
MEMBER
MEMBER
MEMBER
SERIES: XXXX XX
AAMA / NWWDA 101/I.S. 2-97
QUALITY CONTROL & TESTING
AAMA CERTIFICATION
PROGRAM
ACCREDITED BY
A-L-I
®
F-LC35-60X84
AMERICAN NATIONAL STANDARDS INSTITUTE
VALIDATOR
MFR. CODE: XX-X
(PRINTED IN BLACK INK)
A
THIS PRODUCT HAS BEEN
RATED IN ACCORDANCE
WITH NFRC 100
XXX-XXX
B
D
E
C
F
2003
D
MEMBER
G
A Manufacturer’s Code Number.
Code number is required, but
manufacturer may also show
company name
B Air, Water, Structural
Specification Identification
C Manufacturer’s Series Number
E Maximum Size Tested
D Product Type, Performance
Class (design pressure), and
Performance Grade
G Thermal Specification
Identification
F NFRC – assigned
manufacturer’s code
and product line number
AWDI Installation Manual Volume 2- Coastal Windows
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Types of Hurricane Protection
Film, Laminates, Shutters and other Protection
Most hurricane protection is accomplished by the use of
shutters covering the windows and doors, or installation of
windows and doors that contain impact-resistant glazing.
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Impact resistant
glazing consists of
two panes of glass
with a film layer(s)
embedded between
the glass panes
that when the unit
is heated, the film
and glass become
optically uniform
with minimal
lessening of
transmitted light.
Application of the film to
the edge of the glass
panel where it would
cover the glass within the
bite is called an edge to
edge installation, and is
often used in conjunction
with dry glazing installations. Other methods of
application may improve
film performance and
further reduce hazards
but are typically more
expensive to install,
Typical daylight installation of
especially in retrofits.
anti-shatter film
Energy-absorbing catch
systems, used in conjunction with a daylight application
of anti-shatter film, are another mechanism for retaining
and reducing debris hazards. Cables spanning across the
window will impede the flight of filmed glass and absorb a
considerable amount of energy upon impact. These cable
catch systems have demonstrated through explosive testing to be more efficient and effective than the more rigid
catch bar systems described in Section D below.
The impact glass works on the same principle as auto
safety glass in that the glass is shatter resistant, and tends
to stay together even if the glass layers become in pieces.
Impact resistant glass depends on the film for a second
safeguard: being connected to the frame so the glass unit
does not separate from the frame creating the hole that can
cause pressure differences that can destroy a home during
violent winds.
There are applied films that can be adhered to glazing after
the glass is installed in windows and doors and is often
touted as shatter-proof during storms and flying debris.
Unless they are attached to the frame of the window or
door, these films do not satisfy the codes in High Velocity
Hurricane Zones (see chart), but can offer second level
defense.
D
There are three types of anti-shatter film installation
methods. They are:
• Daylighting Installation
• Wet Glazed Installation
• Mechanical Anchored Installation
Daylighting Installation
The application of security film must, at a minimum, cover
the clear area (a.k.a. the portion of the glass unobstructed
by the frame) of the window.
This minimum application to the exposed glass without any
means of attachment or capture within the frame, termed
"daylight" installation, is commonly used for retrofitting
windows.
AWDI Installation Manual Volume 2- Coastal Windows
Wet Glazed Installation
The wet glazed installation is a system where the film is
positively attached to the frame using a high strength
liquid sealant such as silicone. Frequently used for field
retrofits, the method allows the flexible frame to deform
slightly, reducing glass fragments entering the building
and offering more protection than the daylight installation.
The wet glazed installation system is more costly than the
daylight installation system, but is less expensive than the
mechanically
attached or anchored
installation system
described below.
Mechanically
Anchored/Attached
Installation
Anti-shatter film is
most effective when
used in conjunction
with a blast-tested
anchorage system.
While a film may be
effective in keeping
glass fragments
together, it may not
30
Typical mechanically anchored
installation of anti-shatter film
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
be particularly effective in retaining the glass in the frame.
Securing the film to the frame with a mechanically connected anchorage system further reduces the likelihood of
the glazing system exiting the frame. Mechanical anchorage systems employ screws and/or batten strips to attach
the film to the frame along 2 or 4 sides. Because additional
framework is necessary, the mechanical attachment
method can be less aesthetically pleasing than the wet
glazed installation system.
moisture that does not dry will prevent the development of
the full adhesive bond strength. Anti-shatter film should be
carefully examined and chosen for its physical, optical, and
thermal characteristics, with special consideration given to
the adhesive used, the window thickness, and the window
area. Also, window frame systems must be capable of
transferring the load collected by the glazing system.
Corner welded frames are preferred over frames constructed of individual components.
All application and attachment methods can be installed
on-site in either steel or aluminum frames. While some
mechanically attached systems may be used for a wide
variety of windows, others are designed for a particular
type of window frame. Certain types of window frames may
require a custom fabricated anchorage system.
The analytical tools that evaluate the likely performance of
façades in response to blast loads are used to demonstrate
compliance with established blast criteria or performance
specifications. Many of these performance specifications
contain the criterion that the façade must be a balanced
design. The objective of this criterion is to realize the
capacity of all the materials, maximize the potential energy
dissipated due to deformation, and manage the failure
mechanisms. This is accomplished by assuring a controlled
sequence of failure. The performance criteria of the existing
façade systems will determine the effectiveness of the
existing mullions, connections between the different
components, and the anchorages to the structure.
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In addition to considering the various methods of installation, the designer must consider the thickness of the film
and the task of positioning the film on the glass. A lighter
weight or thinner film eases installation. Water used to
aid in positioning the film during application must be
thoroughly extruded as the film is not very permeable and
Sq
. Fo
Ins
ot2
ura
Dis nce
cou Pre
mi
nt
u
m
ion
lat
st P
er
rm
sto
Yes
Yes
Yes
Yes
Yes
Yes
Partial 6
Partial 6
No
Yes
Yes
Yes
$16-$25
$35-$50
$8-$12
Yes
Yes
Yes
Hurricane Screens
Rigid
Flexible
Yes
Yes
Yes
Yes
Yes
Partial 6
Yes
Yes
$15-$22
$10-$15
Yes
Yes
Laminated Glass 8
Yes
Yes
Yes
No
$27-$37
Yes
Co
Hurricane Shutters
Accordion
Rolldown
Panel4
Pre
-
Pas
s
ive
Pro
t
Ins
ect
tal
ion
act
mp
le I
all
Sm
Lar
g
eM
iss
Mi
ssi
ile
Im
pa
ct
Guide to Window Protection in Hurricanes
MIAMI-DADE CODE-COMPLIANT
NON-MIAMI-DADE CODE-COMPLIANT
Plywood 4, 5
No
Yes
No
Yes
$2-$4
No
No
No
Yes
No
$20-$40
No
No
No
Yes
No
$10-$15
No
Partial
Yes
Yes
No
$15-$35
No
No
Yes
Yes
No
$12-$22
No
No
Partial
Yes
No
$5-$12
No
No
No
No
No
$3-$5
No
No
No
No
N/A
$8-$15
No
( 7/16” minimum)
D
Tempered Glass 7
7
Insulated Glass Unit
(Non-Tempered Glass)
Security Window Film 1, 3
(Mechanical Attachment)
Security Window Film 1
(Wet Glaze Attachment)
Security Window Film 1
(Unattached)
Solar Control Window Film 1
Annealed Glass
7
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.
1/4” MAX. SHIM
1X P.T. WOOD BUCK
1/2”
Bottom Line: The method of measurement will product
the best possible chance to install the new window with
a minimum of damage to the existing opening, and a
minimum of repair; and allow proper weather-sealing.
How to Remove the Old Window
Remove any of the operating panels or sash.
The exterior stucco
finish must be cut
back to the edge of
the flange. This is
possible to do with a
Fein oscillating tool
and a masonry blade.
Carefully determine
where the flange edge
is on all 4 sides.
Step 1.
Remove all
Using a framing
Frame and Glass
square or other
straight edge, cut the
stucco to the flange
tips on the top, bottom and sides. You
should be able to get
a clean cut with no
damage.
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The mistake too often made is to order a window too small
for the opening, and/or ordering a window that needs the
mounting flanges cut off in order to make it fit in the
opening, but rendering it impossible to properly seal it
on the outside and trim in on the inside.
While it may seem simpler to add to the measurements,
this method allows for some adjustment for irregular
situations. The 1/2” deduction is for the shimming.
The 1” addition is for the flange (1/2” protrusion on all
4 sides). If, after analysis, it is obvious that the shimming
is a great deal more or a great deal less, adjustment can
be made. If the sill is a ?” thick stone sill, modest
adjustment in the ordered Height can be made, as well.
The following techniques are designed to allow proper
measurement, proper removal of the old window,
minimization of opening damage, proper preparation of the
remaining opening, proper mounting of the new window to
meet applicable codes, and proper finishing of the newly
installed window in a weather tight and architecturally
acceptable fashion.
How to Measure
Understanding how the old window was mounted will help
make proper measurement possible. The diagram shows
typical mounting in block and wood frame. Both utilize
some form of wood “buck” either a full buck or wood pieces
used to approximate the function of the “buck” which is to
make amounting surface to which the window can be
mounted, while allowing the ?” surrounding flange projection to butt against it effecting an overlap perimeter joint..
Allowing for an approximate 1/8” to 3/16” shim space, the
actual opening (hidden behind the exterior stucco and
interior wallboard, sill, trim or caulk seal) up to 1” larger in
height and width than the exposed window might indicate.
Ordering a new window based on that assumption would
create a problem putting the new window in the opening as
it must be placed in the opening from the outside to allow
the flange to overlap the “buck” for a proper weather seal.
D
The AWDI method of window removal and install prescribes
proper measurement as shown. Measure from the inside of
the wallboard on the right to the inside edge of the wallboard on the left. Measure from the upper inside edge of
the wallboard to the sill. Subtract 1/2” from the width and
height dimensions, and then add 1” to each.
Therefore, a measured width of 34-3/4 will result in an
ordered flange tip-to-tip Width of 35-1/4” (34-3/4, minus
1/2”, plus 1”). A measure height of 56-1/8” will result in an
ordered flange tip-to-tip Height of 56-5/8” (56-1/8”, minus
1/2”, plus 1”).
AWDI Installation Manual Volume 2- Coastal Windows
1/2”
1/2”
Next, using the Fein
oscillating tool and a sealant blade, free the window
on the inside from
any caulked or sealed
joints on the sides,
top or bottom.
Remove any of the
operating panels or
sash.
Tape any remaining
glass panes, and
using the Fein oscillating tool, remove
the glazing beads,
glazing compound,
and glazing adhesive
and carefully remove
the stationary glass
pane(s).
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1/2”
Step 2.
Remove
Anchoring Screws
and Cut Perimeter
Seal
1/2”
©2005-2014 - All Rights Reserved. Do not reproduce without permission.
If there is a
mullion or other
separating piece, if
possible use the
Fein oscillating tool
to cut it free from
the window frame.
Remove the inside
sill (if any).
Remove all
mounting screws
from the window
frame.
Step 3.
Pry out old frame
and shims.
Minimize damage
to stucco
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If possible, cut the
side frame pieces
through to release
the frame from the
opening.
If unable to cut the frame, you can collapse the
window frame, carefully as shown. The old window
should be out with minimum damage to the opening.
How to Prepare the New Opening
Clean any debris from the opening, including old
shims, wood mounting materials and mounting
screws.
Measure the Height
to determine if the
old sill is at its
proper height, or if
the old window
“floated above”.
The sill needs to be
established at the
proper dimension,
and it needs to be
flat and level the
full width of the
underlying
framing.
Step 4.
Mount New Buck 1/2” to 3/4”
thick to allow new unit
into opening without
removing flange
D
Thinset, or similar,
can be mixed and
poured into the
space to create the
proper sill width,
level and create the
proper height dimension.
If possible, a properly sized wood framing member or
vinylumber pre-formed pvc board can be inserted to
create the flat, level sill in its proper position. This
will eliminate practice of removing flange to get
new window into opening.
AWDI Installation Manual Volume 2- Coastal Windows
Using new “buck” material, place new mounting
bucks on the jambs and header. Butt them together
at the corners, and caulk seal all joints.
Cut and prepare a proper sill pan (if appropriate), or
install a pre-formed sill piece to effect proper drainage
and proper mounting of the new windowsill and a
back dam to direct all water to the outside.
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.
Two goals must be met. First, no water that enters
the installed window cavity should get behind the
window and into the interior. Second, no moisture
shall enter the cavity where it can condense and
become trapped.
All gaps over 1/8” that are sealed with caulk, must
use backer rod. All gaps over must be covered with
trim, or any means to block water penetration into
the opening.
The preferred method for trim/sealing the interior
and exterior is Snap Trim. Pvc windows are fitted
with an accessory groove into which trim can snap
that will bridge any gap, and maintain drainage out
of the cavity and away from the window as shown.
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Aluminum windows can utilize two piece aluminum
snap trim, where one piece is screw anchored to the
frame, and the finish piece is snapped in place to
effect a complete trim cover of the perimeter joint.
All snap trim is cut to where the header portion
passes over the top edge of side pieces, and where
the bottom piece fits between the 2 side pieces.
This effects the proper “shingle-style” overlap
drainage.
Exterior joints can be caulked, interior joints are best
left un-caulked to maintain vapor barrier continuity
in warm/humid coastal areas.
If the stucco is damaged, the new installation will require a lot
of repair as shown. Be careful, put in new bucks, and you can
avoid the problem, and comply with code.
D
How to Install the New Window
A new window must be installed on a mounting buck
with stainless steel fasteners at the appropriate code
required quantity, with the fasteners of sufficient
length to penetrate the rough opening frame (block or
wood frame).
Plumb, square and level the window in the opening,
being careful to keep it as centered as possible.
Stackable, plastic shims, should be placed under
each mounting hole.
How to Finish the Installation
It is important to seal the new window in the opening
to direct any water away from the interior and into
the drainage system of the wall. That is usually
behind the stucco, and down to the bottom weep
within the wall.
AWDI Installation Manual Volume 2- Coastal Windows
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©2005-2014 - All Rights Reserved. Do not reproduce without permission.