Prodex attic insulation prevents cold, radiant heat and vapor transfer. Prodex attic insulation is a reflective insulation, radiant barrier, and vapor barrier.
Prodex attic insulation is ideal in warm and cold climates. Installing a Prodex attic insulation means that the heat of the sun will be reflected back out of your attic instead of crossing the airspace to be absorbed by the insulation on the attic floor and then radiated down into your home below. Similarly, adding Prodex attic insulation on your attic floor will reduce the loss of heat from the attic floor to the roof sheathing.
Because heat rises, you'll have more winter heat loss through your roof than through your walls; therefore, it's more important having a higher R in the roof than the walls - The Prodex 15.67 R-value (single layer) and 21.10 R-value (double layer) in roof applications. Unlike fiberglass insulation, these R-values are unaffected by humidity! The radiant barrier component of Prodex addresses the summer heat gain. Heat gain is higher in the attic because the sun is beating down on it all day (it's not uncommon to have summer daytime temperatures in an attic cavity that exceed 140 to 150 degrees F). Prodex reflects 97% of radiant heat (the primary source of heat-flow).
Adding attic insulation is paramount to creating a more comfortable and energy efficient home, keeping you cooler in summer and warmer in winter. By properly installing an attic insulation with foil can lower your air conditioning and heating bills and can potentially extend the life of that equipment. Learn how Nasa developed this technology.
Types of attic insulation
- Prodex Total = radiant barrier + reflective insulation + vapor barrier. click for more...
- Cellulose, won't prevent radiant heat transfer, click for more...
- Fiberglass, won't prevent radiant heat transfer, click for more...
- Spray foam, won't prevent radiant heat transfer, click for more...
- Rockwool, won't prevent radiant heat transfer, click for more...
While other types of attic insulation are made to resist or impede the flow of warm air, a reflective attic insulations reflects back infra-red energy from the sun so it does not penetrate the building. It can also reflect back radiant heat inside the house so it does not escape. The concept is simple: each unit of radiant heat energy that is reflected away from your home in summer and each unit reflected back inside during winter means less operation of your air conditioning and heating systems, less wear and tear on your equipment, and less money you pay in utility costs. Studies show that a reflective attic insulation with 5mm (1/4 inch) closed cell polyethylene foam sandwiched between two 99% pure aluminum, low emissivity surfaces can save as much as 17 percent on air conditioning energy costs.
Attic Insulation with foil Installed During New Construction
Attic insulation with 5mm (1/4 inch) closed cell polyethylene foam sandwiched between two 99% pure aluminum, low emissivity surfaces are not affected by moisture and can completely replace older insulation materials in warmer climates. Reflective insulation can also be used effectively in conjunction with other bulk insulation materials in colder climates.
In a typical home, up to 30 percent of heat is lost through the roof. Adding attic insulation is an easy upgrade in comparison to insulating walls, floor or the roof deck in an existing building. Adding a radiant barrier is the most common home insulation retrofit project. Reflective insulation used as a radiant barrier can be easily added to an existing attic as it hangs below the rafters.
Energy Savings
A radiant insulation for attics with 5mm (1/4 inch) closed cell polyethylene foam sandwiched between two 99% pure aluminum, low emissivity surfaces also gives the fastest time to payback. The cost of insulation is usually measured as the time to payback the initial cost of installation through energy savings. Payback is calculated by dividing the initial cost of the insulation by the annual amount of savings in energy costs. Most agencies and manufacturers report the payback time on any insulation job as 5-6 years. Heavily insulating the attic is usually seen as a worthwhile investment as an average home will stand for 100 years or more.
Economic gains from installing reflective insulation as a radiant barrier in the attic are well documented. Estimates are that insulating an un-insulated attic saves 25 percent on heating costs in cold climates while adding a radiant barrier to an insulated attic saves 12 percent in warm climates. The Oxford City Council has estimated that the cost to add extra insulation to an attic will pay back in 5-7 years while installing insulation in an un-insulated attic will pay back in 2 years.
Attic Insulation with foil Retrofit
Research conducted by the Florida Solar Energy Center (FSEC) has shown that the installation of an attic insulation with foil can generate significant financial savings. About 22 percent of the heat gain in a typical Florida house comes in through the attic. Installing an attic insulation with foil reduces heat gain through the roof by about 40 percent. This equates to a savings of 8 to 12 percent on the annual electricity costs for air conditioning in a typical Florida home. The summer peak energy use savings was as much as 27 percent. This study also showed that the average peak reduction from the radiant barrier system was three times as great as the savings produced by adding more fiberglass insulation (a change from R-13 to R-19).
Whole house tests run by the Mineral Insulation Manufacturers Association and the Oak Ridge National Laboratory show the average reductions in ceiling heat flow from the addition of a radiant barrier stapled under the rafters between 24 and 30 percent compared with R 19 attic floor insulation and no attic radiant barrier insulation. The U.S Department of Energy Attic Radiant Barrier Fact Sheet (DOE/CE-0335P) states that reductions in the cost of cooling can reach up to 17% by proper installation of an attic radiant barrier.
Attic Insulation with foil - Installation Options
Attic insulation with foil is easy to install. It can be incorporated into new building construction on top of the rafters before adding the roof decking or on the bottom of the roof truss chords or rafters. In existing homes, a radiant barrier can be easily added to your attic by attaching it to the bottom of the roof trusses. It is important that the reflective side of the insulation face the airspace of the attic if using a single sided reflective insulation product. Click for installation methods.
An attic insulation with foil is the most effective when there is at least a 1/2" or more airspace between the insulation and any adjacent material. Furring strips can be added to create additional airspace if needed. Reflective insulation can rest directly against some other insulation materials like fiberglass insulation and still maintain ample airspace as the fiberglass batt is primarily composed of airspace. Drywall can also be directly installed over reflective insulation. Reflective insulation attaches with tape, glue, nails and staples noting that tape doesn't adhere well to either concrete or wood. After installation, all seams should be sealed with reflective tape. Heat and cold will seek the least resistance, it will find its opening at the seams; Therefore, taping the seams improves performance.
In high moisture content homes, a perforated foil insulation for attics would be preferable if for use stapled on top of existing insulation on attic floor.