Windows, doors and the rest in a maximum power envelope of the house is always a compromise between energy efficiency and livability. Living in a house without windows will be the most depressing … but also the most energy efficient windows or skylights can not compare as a thermal barrier walls and insulated ceilings. So when you install a window in the wall, cutting a hole in the best thermal barrier of the house. In other words, well-built window can have a value of RR-3, while the outer walls of the house usually have a value of about 20 RR … which means that the window is less efficient 17 points that the walls. This leaves a window to be a losing significant heat to the wall.
If you have been shopping for new or replacement windows, you may experience some confusing terms have been made to demonstrate the ability of a material or combination of materials to insulate a room to another. In other words, “keeping outside.”
Many people are familiar with the term R-value, a term coined to assess a particular substance in its ability to resist the flow through “hot”. R-value is generally associated with a wall or attic insulation material. To address the concerns of insulation materials used as hits or fiberglass blown cellulose and fiberglass. It is often said, “four inches or twelve inches which gives the R-19 R-38 or R-value. A higher number indicates greater resistance to the flow of heat from one place to another.
U-value is a term coined to indicate the thermal efficiency of the material together as a unit, such as windows, skylights drive or group of ports. By comparing the value of R L value, the higher the value of r is considered good, while a value of L of the lowest note being preferred. An R-30 value is better than the R value of 20 and a U value of 0.50 is better than the U value of 0.75.
Low-E coatings for improving or limit the window to reflect the thermal radiation of the sun through the window. This is achieved with the coating on the glass, such as color windows with the machine. This term is very simple and easy to understand. Low-E coating is most desirable for a clear and sunny weather. Weak and also limit discoloration of sun and fabrics and carpets laundering.
I often think this is a smoke screen used by window manufacturers confuse the average person, when you buy a window of the house. These terms imply that windows, doors and skylights, very effective unit. It is not worth. Some are better than others only by a small amount.
If you build a new house or buy a second-hand houses in the energy market today, it is useful to examine the thermal efficiency of a home. Windows, skylights and doors is an important factor in maintaining a comfortable living room. Large windows and large doors to the energy bill.
My mother summed up last year with the phrase: “What … you have the power company or something … light.”