District of Columbia municipal planning director Ben W. Gilbert expressed second thoughts yesterday about proposals for a new retail mall on the site of a Metrobus garage in northwest Washington.

After conferring with Douglas N. Schneider Jr., director of the city's Department of Transportation, the two officials issued a statement declaring that location of a 50-store complex on Wisconsin Avenue near Jenifer Street NW would be "inconsistent" with current zoning goals for that area.

On Tuesday, Gilbert had described plans for a combined retail center and bus facility as innovative and worthy of consideration by city planners.

Yesterday, said Gilbert, "when we saw the full scope" of the proposals as reported in The Washington Post, "we concluded it was balanced the wrong way . . . we don't want to develop to such a point" that residential neighborhoods would be adversely affected.

In their formal statement, Gilbert and Schneider said the proposals for a retail complex at the bus garage "are, in our view, inconsistent with the Friendship Heights plan," a development guide for the overall area around Western and Wisconsin Avenues, in both Maryland and the city.

The Friendship Heights area was the subject of significant reductions is permitted development density in 1974 and the D.C. Zoning Commission has scheduled a hearing for Jan. 26 to consider formal action on a draft plan for the District part of the area.

According to Gilbert, the draft proposal deals primarily with nonzoning elements and criteria for planned development.

Under previous zoning decisions, he added, a major portion of the Metro bus tract should be devoted to medium high-rise apartment development.

"The city govenment believes that further commercial expansion of the kind being discussed for the Metro garage site should occur in the down town area of the District in areas already zoned for such development," said Gilbert and Schneider.

Herbert Miller, of Western Development Corp., one of three groups that have suggested that Metro develop the bus garage site, said yesterday his company would be willing to work with transportation authority officials on environmental studies that would be required before designing any building. He also expressed an interest in developing the location as a mixed retail-residential project - one that could conform to current zoning, which permits commercial development along Jennifer Street but not on Wisconsin Avenue.