The answer to 'difference between flat roof and pitched roof' is that flat roofs are horizontal or nearly horizontal surfaces, while pitched roofs have a slope that allows water and snow to drain off. Flat roofs are commonly used on commercial buildings, while pitched roofs are more common for residential homes.
Flat roofs generally have lower installation and maintenance costs, but they require more frequent inspections and repairs to prevent leaks. Pitched roofs, on the other hand, are more durable and can withstand heavy snow and rain loads, but they are more expensive to install and maintain.