Sfd demolition permit -- for existing sf spa and 46 lf of 46" max county std ret. Wall w 36" max free standing wall on exst sfd note: _ it may not be possible to rebuild. _ the fact that there was an existing structure on your lot does not guarantee that you will be able to replace it if it is demolished. Existence of a structure does not "grandfather" its use if it is removed. Please see the zoning counter at the kearny mesa pds offices (55 overland ave., suite 110) for more information.