Frequently Asked Questions
Q: How does my order get to me?
After placing your order one of
our representatives will phone you and
review your order. After personally confirming that your order is complete, we
process your payment and place the order to the factory nearest your address,
just like your local dealer. Within 48 hours we will let you know of your
delivery date and approximate time of delivery. We will phone you the day before
the delivery to remind you and let you know what time your windows are coming within a 3 hour time period. All windows are
delivered by the factory.
What type of glass is standard in the windows you sell?
windows sold at 1stwindows come standard with clear, dual paned
glass - that's two individual glass panes. Dual paned glass is
superior to a single pane window in both energy efficiency and sound
transmission reduction. Many other glass types are available such as
laminated, azurite, solar bronze, etc. Click
here to learn more about the various glass types we offer.
What is "Low-E" Glass?
Low-E (Emissivity) glass products give you
year-round energy savings and comfort by helping manage the sun's energy
and the heating system energy in your home. Low-E glass products are
coated with microscopically-thin, optically transparent layers of silver
sandwiched between layers of antireflective metal oxide coatings. In the
summer, Low-E glass products let in visible sunlight while
blocking infrared and ultraviolet solar energy that drives up cooling
costs and damages curtains, window treatments, carpeting and
furnishings. And in the winter, Low-E glass products offer greater
comfort and reduced heating costs by reflecting room-side heat back into
Emissivity is a measure of how much heat is emitted from
an object by radiation. Heat is transferred to and from objects through
three processes: conduction, convection, and radiation. For instance, on
a hot night, heat will be conducted through a window from the
outside, causing the inside pane to become warm.
natural circulation, of the air in the room past the window will
transfer some of that heat into the room. But the window will also radiate
heat as infrared waves, which will warm objects throughout the room.
This radiative heating is why you can feel the heat of a red-hot piece
of metal (for instance, a heating element on an electric stove) from
several feet away. Low-Emissivity, or low-e, coatings are put on window
panes to reduce the amount of heat they give off through radiation. In
hot climates, where the outside of the window will typically be hotter
than the inside, low-e coatings work best on the interior of the outside
window pane. In cold climates, where the inside of the window is
typically hotter than the outside, the low-e coatings work best on the
inside window pane, on the side that faces toward the outside.
Q: What is U-Value?
A: The U-value, also called the
U-factor, is a measure of how well heat flows through an object (thermal
conductivity). It is also referred to as the heat transfer coefficient
or the coefficient of heat transmission. The U-value is measured by how
much heat (Btu) flows through a certain area (a square foot) each hour
for a certain temperature
difference (°F), so it is measured in Btu/ft2-hr-°F. The
U-value is the reciprocal of the R-value: the lower the U-value, the
better the insulation value of the material. Many building and
insulation products have their U-value indicated on their label. A
U-value of 0.35 or less is recommended in cold climates. In warm
climates a low U-value is helpful during hot days or whenever heating is
needed, but it is less important than SHGC (Solar Heat Gain
Coefficient - see below).
Q: What is R-Value?
measures insulating power. The higher the R-value, the better the
insulating power. To find the R-value you need, check with your local
utility company. Recommended levels vary depending on where you live.
The R-value is the inverse of the U-value. Remember: If you install more
insulation than necessary, you'll waste money. When having insulation
installed by a contractor, be sure to discuss what R-value is best for
your home. Ask retailers and home installers for a fact sheet on
insulation before buying. The fact sheet, required by the Federal Trade
Commission (FTC), tells you the type of insulation, its R-value, and the
area it will cover. When the contractor installs your insulation, they
must give you a contract or receipt showing the insulations R-value,
coverage area, and thickness. If loose-fill insulation is installed, the
number of bags used also must be included.
Q: What is Solar Heat Gain
A: The Solar Heat Gain Coefficient
is the fraction of incident solar radiation admitted through a window, both directly
transmitted and absorbed
and subsequently released inward. SHGC is expressed as a number between
0 and 1. The lower a window's solar heat gain coefficient, the less
solar heat it transmits. A SHGC of 0.40 or less is recommended in warm
climates. In heating-dominated climates, a high SHGC increases passive
solar gain for the heating, but reduces cooling season performance. A
low SHGC improves cooling season performance, but reduces passive solar
gain for heating.
Q: What is Visible Transmittance
A: The visible transmittance (VT)
is an optical property that indicates the amount of visible light
transmitted through the glass. VT is expressed as a number between 0 and
1. The higher the VT, the more daylight is transmitted. A high VT is
desirable to maximize daylight.
Q: What is Air Leakage (AL)?
A: The air leakage rating (AL) is
a measure of how much air leaks through the crack between the window
sash and frame. The rating reflects the leakage from a window exposed to
a 25-mile-per-hour wind, and is measured in cubic feet per minute per
linear foot of sash crack. Heat loss and gain
occur by infiltration through cracks in the window assembly. The lower
the AL, the less air will pass through cracks in the window assembly. An
air leakage rating (AL) of 0.30 cfm/sq ft or less is recommended.
Q: What is an NFCR rating?
National Fenestration Rating Council (NFRC) is a non-profit
collaborative of manufacturers, builders, designers, government
officials, utilities and consumers which provides unbiased
energy performance ratings for window, doors and skylights (or
"fenestration"). NFRC’s labels provide
product-specific performance ratings for technical qualities
such as U-factor (the rate of heat loss from your home through
the window), and Solar Heat Gain Coefficient (how much heat your
house gains from the sun as a result of the window’s
performance). Look for lower U-factor and appropriate SHGC
numbers for highest efficiency performance in your area of the
Q: What is Energy Star?
Star windows is a program designed to help consumers identify efficient
windows, doors and skylights. By choosing Energy
Star window products you can cut down your heating and cooling costs, and
make your home more comfortable at the same time. Energy
Star labeled windows are twice as efficient as the average window
produced just ten years ago. Want to know more about Energy Star? See our Energy
Star information page.
How to select new windows
Benefits of Energy Star windows
Tips/Ideas for home improvement projects
Learn how to install your own windows