Should I invest in new
windows?
Homeowners who reside in areas that are extremely hot
in the summer, really cold in the winter or both should invest in good quality,
energy efficient windows.
Here are some of the more common types of
windows:
Fixed windows. These don't open at all.
For instance, often the center part of a bay window is
fixed
Single-hung windows. These are the same
as the double-hung units except the top sash doesn't move.
Casement windows. Casements are
hinged on one side and often are operated with a crank. Look for multi-point
locking, especially on tall ones, otherwise they won't close tightly. There is
also egress hardware that hold the windows open if need be.
Sliding windows. Sliders have two or
more panels that cross each other when they open, like a double-hung set on its
side. They are unobtrusive, easy to open and close, but hard to keep
clean.
Double-hung windows. This window has
two sashes that move up and down, one behind the other. In pre-air-conditioning
days, the most common practice was to open the window a little at the top, so
rising hot air could escape, and more at the bottom to let in cool breezes.
Modern double-hung windows, including replacement versions, offer sashes that
tilt toward you. When you tilt the sash inward, you can clean both sides of the
window from inside the house - a real convenience.
Bay windows. Bay windows are a
combination of three windows that angle out from the house. The center unit is
parallel to the house, while the side units sit at an angle. Bay windows that
curve gradually rather than forming angles are called bow windows. If the bay is
formed with right angles, it is called a box bay. A small box bay with a glass
top and used in the kitchen is called a garden bay.
Awning windows. These windows are
like casements turned sideways. They're hinged at the top. The crank turns the
bottom out, allowing in air, but not rain. Typically, they are used in
combination with a fixed
window.
Who should I buy windows from?
A consumer should select a window manufacturer who
manufactures and sells energy efficient products (i.e. meets the recommended
U-factor and Solar Heat Gain Coefficient in your climate), has a reputation for
service and stability, and provides a warranty on the unit. We recommend that
you buy products from an Efficient Windows Collaborative member manufacturer
since these manufacturers have made a commitment to participating in the
National Fenestration Rating Council (NFRC) certification and labeling process
and in the ENERGY S®
Windows program. Many manufacturers will also participate in the American
Architectural Manufacturers Association (AAMA) and will have a permanent label
on the product indicating their participation. Others will participate in the
Window and Door Manufacturer's Association (WDMA), also with a corresponding
label or insignia. Membership in all of these organizations is an indication
that you are dealing with a manufacturer who cares about the quality of their
product and the product's energy efficiency.
Why are my windows drafty and will new windows stop the draft?
Drafty windows and air infiltration could have
several causes. Improper installation is often the culprit but not always. If
the windows were improperly installed, the defects can normally be corrected
without removing or replacing the window. Proper caulking and flashing should
prevent perimeter air leakage If the problem is installation, you will have to
work with the builder or a contractor to correct the problem. If the leak is
between the frame and the sash and the window has been installed square, plumb,
level and is not twisted or racked, the problem may be construction of the
window or window design. If your windows are not efficient in your climate and
particularly if it does not have insulated glazing, the air may not be leakage
but simply cold room air flowing down the surface of the window. As the window
surface becomes colder, it cools the room air next to it. This cooled room air
is then heavier than the warmer room air further into the room. Because the
cooled room air is heavier it sinks toward the floor and is replaced by warmer
room air, which is then cooled. This process can result in noticeable air flow
but it is not air leakage from the outside. Replacement of the window by an
energy efficient window is the solution here.
Where do I go to buy an efficient window?
Before you buy a window, we recommend that you do
your research via the web and written material and then shop around. Windows are
complicated devices, made more complicated by the fact that recommended window
types vary by climate. Climates where heating is very important have different
product recommendations than climates where cooling is more important.
First, educate yourself about what kind of window
is right for your climate and needs. Learn about the NFRC and ENERGY STAR® labels and why they
are important. We recommend that you go to the SPONSORING MEMBERS section of
this web site, click on manufacturers, and become familiar with Efficient
Windows Collaborative members who sell products in your area. Go to member web
sites, explore their products, information, and materials. Then prepare yourself
to ask questions.
. Windows equipped
with low-emissivity (low-e) coatings allow visible light through, but block
heat. That means heat has a much harder time escaping on cold days and entering
on hot ones. Low-e coatings also screen out ultraviolet rays, which fade
furniture. Some manufacturers make windows "tuned" to hot or cold climates. The
basic difference is that hot-climate windows block more solar radiation to
reduce cooling costs while cold-climate windows admit more solar radiation to
lower heating costs. How effective the window is at holding or rejecting solar
heat is measured as the solar heat gain coefficient. This number is shown on the
NFRC label and ranges from 0.2 to 0.5. If you live in a warmer climate, seek a
lower number; in the colder states, choose a higher
number.
The insulating value of a low-e window can be
improved about 20 percent by sealing low-conductivity argon or krypton gas
between the panes. Krypton is more expensive but insulates better than argon.
Its use allows the window assembly to be thinner. Don't worry, these inert gases
occur naturally in the atmosphere. They are harmless if the window breaks.
Will new windows eliminate condensation?
Energy efficient windows will help reduce
condensation. Here's why: high performance windows with low U-factors result in
inside glass surface temperatures much closer to the room air temperature.
Windows with warm edge technologies and non-metal frames are also less likely to
have condensation on the frame or at the edge of the
glass.
You can find a window professional right
here on the
Home Improvement
Hotline!
