We are not believers in this method of insulation. It has been done for decades in various forms (it began as a foil-like material) and always delivers poor results.
You will get far better performance from a blown cellulose material and doing an energy audit to identify and seal any areas of the attic that have high air infiltration.
I spoke with our certified energy auditor who said the following: “Typically in an attic after an energy audit we recommend air sealing between the attic and conditioned space, sealing off any thermal bypasses, verifying adequate attic ventilation and then adding cellulose insulation to a level equivalent to between R-38 & R-49 as recommended by the department of energy.”
Below are some studies with the pluses and minuses to this system: The Oak Ridge National Laboratory has conducted testing on radiant barriers and has some very detailed available here..
Please contact us if you would like any help with your energy improvements, or to inquire about an energy audit on your home call our office at 314.909.1800.