APOC 36-in x 144-ft 432-sq ft Felt Roof UnderlaymentAPOC organic felts are designed with Tru Breathe Technology. This engineered technology keeps rain and water on the outside of your home while allowing water vapor from cooking, cleaning, bathing and other sources to escape home entrapment. Tru Breathe Technology helps prevent premature damage and rotting of your roof deck materials which can lead to unsafe structures and the development of mold. Make sure you use Tru Breathe Technology on your home