Jamieson, Fausset and Brown on Isaiah 9:10

10. bricks--in the East generally sun-dried, and therefore soon dissolved by rain. Granting, say the Ephraimites to the prophet's threat, that our affairs are in a ruinous state, we will restore them to more than their former magnificence. Self-confident unwillingness to see the judgments of God (Is 26:11).

hewn stones--(1Ki 5:17).

sycamores--growing abundantly on the low lands of Judea, and though useful for building on account of their antiseptic property (which induced the Egyptians to use them for the cases of their mummies), not very valuable. The cedar, on the other hand, was odorous, free from knots, durable, and precious (1Ki 10:27). "We will replace cottages with palaces."