When you're looking to replace your roof, one of the biggest factors is the size of your home. A larger house means more square footage to cover, which directly drives up material and labor costs. For a modest 1,500-square-foot home, you might spend around $5,000 to $8,000, but a 3,000-square-foot home could easily run $10,000 to $16,000. The shape and complexity of the roof also matter, but size is the main driver. It's worth getting a few quotes to see how your home's footprint affects the bo… roof replacement cost by home size 18