When installing a new roof, the biggest decision you’re going to face (aside from choosing a roofing pro) is which materials to use. If you’re replacing an existing roof, your decision is easy — just match the current materials. But, if you’re building a new home, the debate over roofing materials can get a bit more complicated. Before jumping into the pros and cons of each material, consider the size and layout of your roof.

Not surprisingly, the size of your roof will play a large role in determining your overall budget. If you’re using a roofer, it’s helpful to understand how your pro will measure your roof. While many contractors base their estimates on square footage, roofing pros go by squares (each square is 100 square feet). The more squares, the more your project will cost.

Will it cost more to replace a large roof with a simple layout or a small roof with a complex layout? If your roof is steep and loaded with chimneys and other elaborate features, it’s a safe bet that you’ll be spending more on your project. The condition of your existing roof and decking (the base on which your roofing rests) is also another potential cost point. If your decking is damaged, any repairs or replacement costs will be added to your budget. While changing the size and shape of your roof is difficult (unless you’re starting from scratch), switching out your roofing materials is easy. Asphalt shingles are inexpensive, durable and available in a number of different colors and styles — making it easy to find the shingles that complement your home. Average cost of asphalt roofing: $1,700-$8,400.

Composite shingles are becoming an increasingly popular option because of their ability to mimic high-end materials (without the additional expense). Unfortunately, composite alternatives are considerably more expensive than asphalt shingles. Average cost of composite roofing: $6,600.