Insulating your home at Halfvalue.com

What are U-values and R-values
When comparing thermal insulating materials, you'll be faced with these technical specifications:

U-Values
The building materials that are already present in your house have been rated by the construction industry and government housing authorities according to the way the materials conduct heat. For individual materials, these ratings are called K-values and represent the total heat transmitted (per square foot per hour) between the surfaces of two materials when there is a temperature difference between the two of 1 degrees Fahrenheit. When the passage of heat is measured through an entire structure (such as a wall, ceiling or floor), which is made up of several different materials plus air spaces, the rating is called the U-value. The higher the U-value, the more rapidly heat passes from one surface of the structure to another.

R-Values
Adding insulation reduces U-values (but not K-values) by resisting the passage of heat through a structure. The degree of resistance is termed the R-value. Insulation is compared and sold by this rating. Materials with superior insulating qualities have the highest R-values.

What to insulate around the house
Many authorities suggest that in an average house, 35 percent of lost heat escapes through the walls, 25 percent through the roof, 25 percent through drafty doors and windows, and 15 percent through the floor. At best, this is a rough guide. It is best to start with relatively inexpensive measures:

Water heater and pipes
Begin by insulating your water-heater tank and any exposed pipes running through unheated areas of your house. This improvement will result in noticeable savings in just a few months.
'Insulation Pipe Foam'
'31013 13UL PIPE HEAT CABLE'
'Heat Tape W/T-STAT 100''
'TUNCAB6 1 / 2 PIPE INSULATION per 70 EA'
'Insulation'

Radiators
Attach aluminum foils to the walls behind your radiators. The foil will reflect heat into the room before the wall absorbs it.
'ASTRO-FOIL Reflective Insulation'
'Astro Foil - 25' long'
'3 Pack of 2-In. x 50-Yds. Aluminum Foil Tape per 1 RL'

Weather stripping
Seal-off air leaks around windows and doors with weather-stripping materials. For a modest expense, weather stripping provides substantial return economically and also comfort wise. It's also easy to install.
'2 Pack of SF64-25 SHRINK-IT ROLL 64X25'
'Weather Stripping - 1/2" x 1/4" Foam'
'Door Weather Stripping - Magnetic Bronze'

Roof
Tackle the insulation of your roof next, because it's usually considered the most cost-effective major insulating job. It not only reduces fuel bills but can make you eligible for utility company rebates and credits.

Walls
Depending on the construction of your house, insulating the walls may be a sound investment. However, it's likely to be expensive and it will be several years before you recoup your initial investment.

Floors
Most floors are insulated to a certain degree by carpet and rugs. But, adding insulation between the floor joists is not usually cost-effective. Let your comfort be the deciding factor.
'R-50 Insulation Kit for Battic Door Attic Stair Covers (Fits Both 22" x 54" and 25" x 54" Sizes)'
'STANLEY CONSUMER TOOLS #10-113 Insulation Cutter Knife'
'Ideal 61-787, Insulation Tester'
'KLEIN TOOLS Bell-System Pliers - Long-Nose Insulation Skinner Model D2291'
'KLEIN TOOLS Pocket Knife - 2-Blade - Insulation-Slitting & Sheepfoot Model 1550-10'