Get matched with top doorbell installation pros in Raymond, CA

The primary reason that insulation saves you money over time is that it reduces your energy bills by making your home more energy efficient. A crucial part of an insulation system is a properly installed vapor barrier. Local building codes dictate whether your insulation requires a vapor barrier based on the type installed. While some high-quality wool insulation may not technically need a vapor barrier, most municipalities still require one to meet code.

You do not always need to remove old insulation before adding new. If the existing insulation is in good condition—not wet, physically damaged, moldy, or infested with pests—you can add new insulation directly on top of it for a compounding effect. You can also mix different types, such as adding blown-in insulation around existing fiberglass batts.

However, removal is recommended if the old insulation is compromised by water damage or pests. You should also remove it if you plan to install a different type of insulation, like switching from roll or batt insulation to spray foam. If the existing insulation is very old or damaged, you will likely get more benefit from removing it and starting fresh.

Structural insulated panels and rigid foam boards have the highest R-value of any insulation that contractors commonly use, with R-values reaching up to around 8.0. These types of insulation are best in extremely cold climates, but they’re generally preferred for new construction, as they can be challenging to retrofit. Blown-in and loose fill insulation provide the next best insulative value, provided the installation is done properly. It’s important to choose an insulation type that meets your needs based on climate, as maximizing R-value may not always be financially worthwhile if you live in a moderate climate.

Heat lost through uninsulated basement walls can account for up to 30% of the total energy lost through heat transfer to the outdoors. While homes in mild climates won't gain as much benefit from having an insulated basement as those in cold climates, the effects are still noticeable on your energy bill.