The city of San Diego has VERY strict restrictions on granny flats or accessory buildings. I know – we built one and are one of less than a handful of companion unit permits issued in the past decade from the city of San Diego. (In 2006, when we were in the permit process we asked how many permits had been issued for granny flats – the answer was 7 applications, 2 permits – ours was one of the 2. The other one was not under construction at the time.)
The rules are as follows:
– Lot size must be twice the minimum for your area. So if the minimum lot size is 5000sf, you need 10,000 sf or more. If the minimum lot size is 3500sf – you need 7000 or more to qualify.
– Max size of granny flat or guest house is 700sf.
– granny flat must be built on back 1/2 of the lot.
– Then there is the offstreet parking “street wall” issue. You need to show an off street parking spot that meets the street wall setbacks. In most areas this means having a wide side yard, with space in front of your house. We were just shy of this requirement and had to plead for a waiver. Our alternative would have involved cementing our front yard to provide a driveway from our curbcut to the far side of the house.
The city of San Diego, at the time we were seeking our permit, did not really like companion units. Other places in the county were much more lenient about lot size and street wall/parking issues.
FWIW – our granny flat has worked out wonderfully. It was designed with my father in laws wheelchair in mind. My in-laws have enjoyed having autonomy and privacy of having a separate house – but having us to help them if they need it. My kids love having their grandparents right there.
