Insulating Attics and Cathedral Ceilings 

Attic insulation is one of the most important parts of creating a comfortable, energy-efficient home in Indiana. Indiana’s energy code requires that attics in new homes achieve at least R-49 insulation value. Many owners choose to go even higher for better performance, especially in spaces with high ceilings or cathedral designs. 

Spray foam is one of the most effective ways to insulate an attic. Open cell spray foam is popular for roof decks, as it fills every gap and helps prevent air leaks, making it much easier to pass Indiana’s blower door test. Closed cell foam can also be used and is especially useful for creating a vapor barrier in homes with complex rooflines or high humidity. 

Cathedral ceilings require special attention. Indiana code does not allow you to simply spray foam between rafters and call it done; there must be enough insulation thickness to reach the code minimum. For many cathedral ceilings, this means combining spray foam with rigid board or blown-in insulation to reach R-49 or more. Ignoring this requirement is a common reason for failed inspections and higher energy bills. 

In unvented attics, spray foam is also the best choice to prevent condensation and future moisture problems. It not only insulates but seals the building envelope, so hot, humid air cannot infiltrate in summer and warm air does not escape in winter. This protects the structure and ensures a more consistent indoor temperature all year. 

Code Compliance and Best Practices 

Indiana inspectors check both insulation thickness and the presence of ignition barriers in attics and cathedral ceilings. Any exposed spray foam must be covered with a code-approved ignition barrier, such as drywall or a specialized paint. The installation should also include clear labeling of R-value and foam thickness so that inspectors can easily verify compliance. 

Proper attic and ceiling insulation not only helps pass inspection but adds real value to your new build. You get better protection from Indiana’s weather extremes, lower energy costs, and a quieter indoor environment. 

To see how we handle attic insulation, visit our Indiana attic insulation page or get information about spray foam options for your home. 

When you’re ready to insulate your new home or upgrade an older property, our team at Advanced Seal Indiana is here to deliver expert installation, code compliance, and lasting comfort.  

Contact us for a free quote.