The drywall hammer is designed for projects that require precision and accuracy, such as installing drywall or working with small nails. The head of the hammer is smaller and lighter than the roofing hammer, making it easier to control. On the other hand, the roofing hammer is designed for projects that require more power, such as driving nails into hardwood or asphalt shingles. The head of the hammer is larger and heavier than the drywall hammer, making it easier to generate more force.