A granny flat has different names in different countries and regions. It is a secondary suite built as an adjunct to the main property in case you require additional room. It can be a fully self-contained unit with a separate entrance. The granny flat is also known as a garage apartment, a basement suite, a guesthouse or mother-in-law house or accessory dwelling unit. Building codes and local regulations may forbid expansion of a house on a plot of land or construction of such rooms and renting them out, which led to the development of “granny flats” since the codes allow such construction for purpose of occupancy by elderly family members. Since you do have a way out, why not use it, stay within the law and still have additional space?
Follow local laws
It will take a bit of effort, but it is worthwhile to invest time in finding out about:
- Local zoning laws for granny flats
- How much frontage is required
- Process of obtaining permission from local council
- Demand for rental property (if you plan to rent it out)
Take, for instance San Diego laws for companion units (granny flats):
- No more than one companion unit is permitted within one premises and that unit may be attached to the main unit or may be a detached unit.
- If a garage is converted to a granny flat, an additional garage must be erected or parking space must be available.
- Off street parking should be available and access to the parking is not permitted from an unimproved alley.
- Gross floor area of the companion unit is included in the floor ratio calculation for the premises, which is an important factor to keep in mind prior to expansion.
Tips for building granny flats
- Once your permissions and approvals are in place you will select a design and a builder. It is better to go the prefab way and engage a contractor to put the granny flat in place.
- The granny flat design should be such that the entire unit can be a standalone unit by itself, with all amenities such as bathroom, kitchen and toilet. Yet, it must provide continuity to the overall façade and structural design of the main house, if built as an adjunct.
- Provide a separate entrance with some frontage. Front door and windows should face the street. If the granny flat faces north, it is ideal from ventilation and lighting perspectives.
- Design it so that the kitchen, toilet and bathroom adjoin each other to reduce drainage and plumbing lines.
- Consider a prefab granny flat. It will work out cheaper, involves fewer hassles such as clearing rubble generated during construction and it will have better quality.
- Factor in extra electrical load and allow for 100 amperes or so. You may want to have a utilities engineer check your supply to see if it will take additional load. A separate meter for the granny flat will help, should you rent it out.
- Think of heating and cooling. Insulated panels reduce heating bills. Double paned glass windows and even insulated doors will provide not only heat but also sound insulation.
- If you live in an area where it snows then you will want to consider a sloping roof.
- If it is not on the ground floor then you could consider a slope as well as a stair way or think of installing a single person elevator or a wheelchair lift to help easy access to the home and outside. It definitely adds value to your granny flat.
Abide by the law, build a granny flat with these tips and keep your aged relatives close by or just rent it out and recover your investment.