"Window
of Opportunity"
True professionals know it takes more than a hammer to correctly
install windows
and doors ? it takes training on proper installation methods.
By Rich Gibson
Many have the misconception that anyone with a hammer is capable
of installing
windows. Some companies have learned the hard way that this
isn't the case.
Legislators in California, for instance, recently dealt with
several
class-action suits stemming from mold growth within the wall
cavities of homes,
caused in part by water penetration from poor workmanship, misapplication
of
products and non-compatible materials.
When homeowners discover that their insurance won't pay for
the escalating
repair costs, they turn to the window installation companies
to pay for the
damage caused by the poor or improper installation.
Avoid like the plague
How should the contractors protect themselves against situations
like this? The
first step is to arrange for training on proper installation
methods ? even for
those who have been installing windows for decades ? because
new building
methods often dictate changes in current methods and techniques.
Most reputable manufacturers offer product training courses,
in addition to
those offered by industry organizations such as AAMA and WDMA.
Having
independent certification illustrates a company's initiative
and gives it
greater credibility with homeowners. An equally important second
step is to
ensure that installers use what they're learned. What good is
training if it
isn't applied on the job?
In an effective training program, installers learn what constitutes
professional
installation. Typically, the four basic guidelines that every
window installer
needs to follow are:
1. Apply all flashings from the bottom up. Begin at the sill
area, then apply
the jamb or side flashing (overlapping the sill by at least
1 inch). Finish
with the head flashings, again being certain that they overlap
the jambs by at
least 1 inch.
2. Seal overlapping joints with a premium-quality sealant to
prevent wind from
forcing water behind the joints. Although everyone knows that
water runs down
hill, you should also know that it cab be forced to flow sideways
? or even
uphill ? by strong winds.
3. Be certain that all sealants are compatible with surrounding
materials. To
test compatibility, take a sample of each of the materials and
place a 3-inch
piece of masking tape on each. Apply a bead of sealant directly
over the tape
and continue down over the surface of the material at least
6 inches. Tool the
sealant with a blunt object to create a good bond, and allow
the sealant to cure
properly. Then pull the tape away from the surface at a 90-degree
angle. A
compatible sealant will tear within itself and stay adhered
to the raw material.
4. Use only non-corrosive fasteners ? preferably stainless steel
? that are
compatible with surrounding materials. Size the anchor to engage
the structural
materials around the opening by at least 1 inch.
Follow these basic steps to ensure a quality installation ?
but a professional
will take it even further. A true professional understands that
a good install
begins with a good measure. Unfortunately, many home improvement
companies
assign this crucial task to a salesman or another individual
who is not
qualified to properly access and measure an opening. Inaccurate
measuring can
create tremendous problems for even well trained installers,
and result in
delays, cost overruns and corner cutting ? as well as leaking
around the
windows.
A "measure person" must understand many variables
in home construction. Each of
these variables will affect the correct point of measure. To
measure properly,
one must be able to identify the type of wall, the material
the new window will
anchor to, the position of the primary weather barrier of the
home and the types
of trim parts, flashing and sealants that will be required.
A qualified
measuring personal also needs to understand construction and
be able to identify
decayed or damaged structural headers, jambs and sills for replacement.
Most importantly, this individual must know when to ask for
help. For instance,
if an opening needs to be altered, such as enlarging it for
bow, bay or
specialty-shaped window, a professional engineer or architect
may need to be
involved.
As a general guideline, the new window should be at least 1/4-inch
smaller than
the opening. In some cases, such as very large openings or openings
that are
more than 1/8-inch out-of-square, additional allowances must
be made. Leave as
much clearance as necessary to allow the new window to be set
square, level, and
plumb; never fit the new window tight to the opening.
Once a qualified individual has measured the openings, the installer's
job
begins. Windows have become increasingly specialized, so a good
installer will
take measures to become knowledgeable about the type of products
he's
installing. The material a window is constructed of, such as
aluminum, wood,
fiberglass or vinyl, and its design will dictate the type of
flashing methods
and anchors that should be used. Many window types require the
use of a sill
pan, a custom-made aluminum or composite pan that is formed
to fit the opening's
sill. The sill pan is integrated into the flashing to collect
and drain excess
water away from a home's structural components.
Windows are outfitted for various means of attachment. These
include
block-framed products, mid-mounted finned products and externally
mounted finned
products. It is crucial that a professional installer understands
the
limitations of each window and the type of mounting it utilizes.
Fins can be
integrally extruded to the frame or come as separate parts that
are
factory-applied, field-applied or folded out. In some instances,
fins are
structural ? or load bearing ? and in the others they're non-structural.
If
fins are not waterproof, they will require rigid head flashing
(extra field
flashing at the head) to create a watertight joint. If in doubt,
always ask the
manufacturer.
Once an installer has selected the appropriate fastener, the
key question
becomes. "Where should the fasteners be placed?" In
most instances,
manufacturers suggest that the installer apply anchors every
16 to 18 inches
around the perimeter of the window, using a minimum of three
anchors per side.
All fasteners used at the sill need to be sealed to prevent
water penetration
into the wall cavity.
Shimming material should be used at every anchor point. Wood
shims or any
wedge-type shim should always be used in pairs. Although wood
wedge shims are
the most common, plastic shims are a better choice, especially
at the sill
because plastic won't absorb water or compress. Also use additional
shims and
anchors at all lock and hinge locations.
Twisted and racked
Another important point is that new windows need to be square,
plumb, level and
flat throughout the anchoring process. Most individuals understand
"square,
plumb and level," but may not know what "flat"
means. Windows can be racked or
twisted within the opening ? or that the original opening itself
may be twisted.
If an installer doesn't ensure that the new window is flat,
it will lead to poor
operation, early failure ? and unhappy homeowners. To ensure
flatness, stretch
two pieces of string diagonally across the interior of the frame;
the strings
should just lightly touch the center. These can be taped to
the frame and left
to act as a guide throughout the shimming and anchoring process.
Contractors also need to be aware of ever-changing building
codes. New codes
are being adopted throughout the country, as federal and state
legislators deem
them reasonable. First, if building codes are involved, inspectors
must be
notified to approve window installations based on thermal efficiency,
design
pressures, mullion deflections and possible even impact protection
performance.
Required new inspections add further complexity to the window
industry because
installers now have to understand how window ratings are achieved
as well as the
meaning of each value.
Another recent development is that many utilities now offer
rebates for
energy-efficient products. Consumers must purchase windows that
meet stringent
requirements to qualify for these funds. This is important to
the window
installer because, in order to collect this money, many companies
mandate that
the homeowner present the window's label, which often are unknowingly
discarded
by the installer. Collect these labels and leave them with the
homeowner once
the job is complete ? not only for energy rebates, but also
for the care and
cleaning information often printed on them.
Lastly, there is one very important element that sets professionals
apart from
the rest ? respect for the customer's home! Installers need
to protect the
homeowners? belongings from possible damage during installation
and be certain
to leave the job site clean. Keep appearances neat and professional
because
installers represent the company contracted to do the work ?
and they form the
impression homeowners have of the company. It makes very good
business sense
that the impression left is a professional one.
|