Which step in the sequence comes after installing insulation and before finishing the interior?

• A. Seal air leaks
• B. Install vapor retarder
• C. Install interior finish
• D. Inspect for gaps and seal

Answer: (C)

In this sequence, what comes after putting insulation in place is finishing the interior surfaces. Once the cavity is insulated, the next practical step is to install the interior finish because the wall is now a closed, prepared shell and needs to be treated to create a livable interior space. Finishing materials like drywall or paneling are attached to the prepared wall, giving you a smooth, finished surface and a room-ready interior.

Air-sealing and moisture-control tasks—such as sealing air leaks or installing a vapor retarder—are typically completed before or during the insulation stage to protect the wall assembly and avoid damaging finished surfaces. Inspecting for gaps and sealing is a check done during and after the barrier and insulation work to ensure the assembly is tight, but it isn’t the step that directly completes the interior. Therefore, installing the interior finish is the logical next step after insulation in this sequence.