Solomon's house had a floor space of 5000 square cubits.

He built also the house of the forest of Lebanon; the length thereof was an hundred cubits, and the breadth thereof fifty cubits, and the height thereof thirty cubits. 2 Chronicles 7:1

God's house had only 1200 square cubits.

But Solomon was building his own house thirteen years, and he finished all his house. He built also the house of the forest of Lebanon; the length thereof was an hundred cubits, and the breadth thereof fifty cubits, and the height thereof thirty cubits. 2 Chronicles 7:1

Now these are the things wherein Solomon was instructed for the building of the house of God. The length by cubits after the first measure was threescore cubits, and the breadth twenty cubits. 2 Chronicles 3:3