Albert Barnes Commentary 1 Kings 6:9

"So he built the house, and finished it; and he covered the house with beams and planks of cedar." — 1 Kings 6:9 (ASV)

He built the house, and finished it—that is, the external shell of the house. The internal fittings were added afterward. See 1 Kings 6:15–22.

Covered the house—He roofed it with a wooden roof, sloped like our roofs.