SLIDE 1 U-Factor
The rate of heat loss is indicated in terms
- f the U-factor (U-value) of a window
- assembly. The lower the U-value, the
greater a window's resistance to heat flow and the better its insulating value.
What's the Difference between U-factor and R-value? The biggest difference between U-factor and R-value is that U-factor measures the rate of heat transfer (or loss) while R-value measures the resistance to heat loss. R-value is a measure of conductance and resistance.
SLIDE 2
U-Value: Points to Ponder
U-Value – Basically is insulating value. Heat flows from the warmer to the colder side of the window & frame is a complex interaction of all three heat transfer mechanisms Conduction, Convection & Radiation. A single glazed window has the insulating qualities as a sheet of metal. Can be considered a thermal hole in the wall and typically has a heat loss rate ten to twenty times that of an insulated wall.
SLIDE 3
U-Value: Points to Ponder
U-Value of our Window = .3
Competors Window = ?????
SLIDE 4
Solar Heat Gain Coefficient (SHGC)
The amount of Radiant heat that comes thru the window heating the objects and people up leading to discomfort The lower a window's solar heat gain coefficient, the less solar heat it transmits.
SLIDE 5
SHGC: Points to Ponder
Heat is gained from Solar Radiation, regardless of outside temperature. Solar Heat Gain through windows tends to be the single most significant factor in determining the air- conditioning load.
SLIDE 6 SHGC: Ours= ??? SHGC:Thiers= ???
There is no SHGC Standard for this part of the country. WHY? How many days a year would you not want solor heat in your home?
SLIDE 7
How we use Energy
Heating & Cooling Accounts for 45%!
SLIDE 8
The typical U.S. family spends more than $2,100 a year on home utility bills? Unfortunately, a large portion of that energy is wasted
SLIDE 9
How air escapes
Windows & Doors are the 2nd leading cause of Air Infiltration in the home
SLIDE 10
Heat Loss from a House A picture is worth...in this case, lost heating dollars. This thermal photograph shows heat leaking from a house during those expensive winter heating months. The white, yellow, and red colors show heat escaping. The red represents the area of the greatest heat loss.
SLIDE 11 It might be going out the window—literally. Most homes have enough leaks around windows and doors to equal a wide open three foot by three foot window!
Add up all the cracks
Source: US Department of Energy
SLIDE 12 Shown with optional foam filling
Not all vinyl-framed windows are created equal. Some are insulated; some are not. Your Energy dollars could be leaking out of your window frames. At Polaris we fill our mainframes with ENIVIROMENTAL GREEN polyurethane foam. This is the same type of foam that is in your refrigerator which is the best insulating door in your home. Window mainframes insulated with ENVIRONMENTAL GREEN foam gives you:
- Increased energy savings
- Improved condensation resistance
- Increased home value
SLIDE 13 These two windows are the same except for what is inside the vinyl
- frames. The frame on the left is
hollow, while the frame on the right is filled with insulating foam. The hollow window frame allows air to circulate inside the frame; this convective effect is observed by noticing the frame temperature. The foam-filled window doesn't show this effect. These windows are being cooled on the back side with wind at
Thermo gram Source: Lawrence Berkeley National Laboratory
Thermo gram of 2 vinyl windows
SLIDE 14
Is expressed in cubic feet of air passing through a square foot of window area (cfm/sq) per minute. The lower an (AL) number the less air a window will let in. When testing for (AL) the maximum allowed wind speed is 25 MPH.
Air Leakage (AL)
SLIDE 15 Air Leakage: Points to Ponder
When you get away from the protection
- f trees, shrubs and buildings Air
leakage can be your leading cause of heat loss, heat gain in a window.
SLIDE 16 Air Leakage CFM @ 25 MPH
1 CFM 30 CFM
13 Gallons Per Minute 38.9 Gallons Per Minute
Maximum
SLIDE 17 Air Leakage CFM @ 25 MPH 1.3 Gallons Per Minute
UltraWeld Double Hung .01
- Virtually Air Tight
- Performs up to 30 times better
than competitors
