Composition shingles protect homes from the brunt of weather and sunlight, yet they are not the only line of defense. Underlayments play the crucial role of secondary layer of protection beneath the shingles. During heavy storms, wind can push rainwater up the lower side of the shingles, or ice can pack and seep beneath them. Shingles are naturally resilient against these issues, yet they can deteriorate over time or they may not be installed correctly. Without an underlayment, moisture would reach the roof deck substrate and begin to rot the structure.
When a well-built home is properly maintained water is a benefit and a pleasure. On the other hand, uncontrolled water in our homes can cause damage, expense and considerable inconvenience. It can lead to mold growth, rotting wood and structural damage. It can also lead to the loss of irreplaceable personal belongings.