single family to multi-family

[Chris Vair]

Hi all,

I have found a two story house 3/1 on the main floor, 3/1 in the basement.  House is currently zoned for single family.  I went to check out the house and there are kitchens on both floors.  My idea is to add a separate and lockable entrance to the basement dwelling and keep the separate lockable entrance to the main floor.  I also want to add separate electric and water metering so that each floor is separated on utilities.  
My question is this:  Do I have to get the property rezoned?  If so, any strategies or advice?  Other thoughts?

thanks!