The living room does not exist in the facade, since the side wall goes back only to the chimney and there is no rear wall. So, all interior living room shots are made on the Bewitched studio set.
There is a major difference in the facade and the studio set. The facade shows a square corner in the living room wall where the front wall turns and goes back toward the chimney. In the studio set there is an "L" shaped section built into the front wall that connects to the chimney wall.
Figure 1 shows that the exterior of 1164 is not consistent with Figure 2, which illustrates the L-shape due to the corner wall. The right front corner of the house should not be square according to the interior set shot.
Figure 1: The Front of the 1164 Facade As Shown In # 148
Figure 2: The Interior of the Living Room As Shown in # 68
In the studio set itself the major changes seen are in the ceiling. Most often the camera shots are directed so that the upper part of the living room walls do not show. On two occasions, a beamed ceiling that is approximately 10' high is shown. Figure 3 illustrates the beamed, 10' ceiling.
Figure 3: The Beamed Ceiling of the Living Room As Shown In # 244
On other occasions, the upper part of the living room back wall is shown to extend upwards to a height of 12-14', and there is no ceiling as illustrated in Figure 4. This was probably the way the set was generally configured so that lighting, microphones, etc. could be mounted overhead. A ceiling was installed only when the script required the ceiling to be shown.
Figure 4: The Higher Ceiling of the Living Room As Shown In # 222
However, a problem arises with even the 10' ceiling in the living room if any attempt is made to reconcile the studio set to a livable house. The master bedroom is supposed to be located over the living room, which then requires the upstairs hallway to be at a 10' height, which it is not. Another way to make the house plans work would be a step up to the master bedroom, which is not there.