1 Kings 6:10

Andthen he built chambers against all the house, five cubits high Better with R.V. -And he built the stories against all the house, each five cubits high." We ought perhaps to make some allowance for the thickness of floors and roofs. So that the whole height to which this three-storied structure rose may have been much more than 15 cubits, if five cubits were the inside height of each range of rooms. Mr Fergusson (p. 27) says -It hardly admits of dispute that with the requisite thickness of their roofs they make up the 20 or 21 cubits which are necessary to bring up their roofs to the level of that of the Holy of Holies."

they rested on the house i.e. On the shoulders or rebatements mentioned in 1 Kings 6:6. The other ends of these cedar beams were embedded in the outside wall of the encasing story-work.