Adequate roof ventilation reduces cooling bills, extends shingle life, and prevents roof rot and ice dams in winter. Both roof and soffit vents are economical to install and are often overlooked by homeowners. Roof and attic vents protect your house from expensive future repairs. In the summer, good attic ventilation reduces heat buildup. That cuts cooling costs and prolongs shingle life. In the winter, warm, moist air seeps into the attic from the living space below. Good ventilation allows the heat and moisture to escape. That keeps your attic dry and reduces ice dams. Step one in ventilation is creating the proper amount of airflow into the attic. This is a delicate balance and must be determined by a professional.