Frame.HeightRule (Word)
Returns or sets a WdFrameSizeRule that represents the rule for determining the height of the specified frame. Possible return values are wdFrameAtLeast - Sets the height or width to a value equal to or greater than the value specified by the Height property or Width property, wdFrameAuto - Sets the height or width according to the height or width of the item in the frame, wdFrameExact - Sets the height or width to an exact value specified by the Height property or Width property.
If ActiveDocument.Frames.Count >= 1 Then
With ActiveDocument.Frames(1)
.HeightRule = wdFrameExact
.Height = InchesToPoints(1)
.WidthRule = wdFrameExact
.Width = InchesToPoints(1)
End With
End If