The answer to 'how often to replace installation' is that the frequency of insulation replacement depends on the type of insulation and the environment it's installed in. Generally, fiberglass or cellulose insulation can last 15-30 years, while spray foam insulation can last 30-50 years or more. However, insulation may need to be replaced sooner if it becomes damaged, compressed, or exposed to moisture or pests.
It's important to regularly inspect your home's insulation and replace it if you notice any issues. Proper insulation is crucial for maintaining energy efficiency and indoor comfort, so it's a good idea to have a professional HVAC technician evaluate your insulation and make recommendations for replacement or repair as needed.