The answer to 'how often to replace flat roof' is that most flat roofs need to be replaced every 10-20 years, depending on the materials used and the roof's condition. Flat roofs are more prone to leaks and damage over time compared to sloped roofs, so regular inspections and maintenance are crucial to extend their lifespan. Proper installation, quality materials, and consistent upkeep can help a flat roof last closer to 20 years, while neglect or low-quality workmanship may require replacement in as little as 10 years.
It's important to have a professional roofing contractor inspect your flat roof every 1-2 years to identify any issues early on. They can recommend repairs or let you know when it's time for a full roof replacement. Replacing a flat roof is a major project, so it's best to plan for it and budget accordingly.