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ADU Accessory Dwelling Unit

Discussion in 'Planning and Zoning' started by matthew easley, Nov 2, 2018.

  1. matthew easley

    matthew easley Registered User

    Nov 2, 2018
    Likes Received:
    Need some help please. I am looking to buy about 5 acres and build approx 2500 sq ft house. On the same property I would like to build a detached house for my mother to live in. I contacted the counties planning and zoning department and they provided me the information I'll copy and paste below. It still leaves me with a lot of questions.
    1. Floor area. Is this just heated area and measured by measuring exterior walls. Or all area within the exterior walls. Would a 900 sq ft ADU with a 450sqft garage count as 1350sqft floor area?
    2. Is a second floor measured and added to the first floor - floor area? Or is the county just looking at the footprint and a second story could allow me to get over 900sqft for the ADU? I'm not trying to build anything extremely big but I am concerned 900 is a little small for someone to live in. I was hoping for closer to 1200.
    3. Do you think I could build a 3 car detached garage and finish 900sqft above it? What would keep me from adding more square footage later?
    4. Lastly, what keeps me from building the garage and then finishing a livable space above it afterwards?

    I appreciate your thoughts and insight.

    Section 10.4
    Conditions for Specific Uses
    Accessory Dwelling Units
    No accessory dwelling unit shall be constructed, or established within the
    principal dwelling, on a lot less than 32,760 square feet in area or the minimum
    required for the zoning district in which it is located, whichever is greater.
    No more than one (
    1) accessory dwelling unit shall be established on a single
    lot of record. Accessory dwelling units shall be located on the same lot as the
    principal dwelling unit.
    Maximum Floor Area
    Accessory dwelling units shall not exceed forty
    percent (40%) of the
    floor area of the principal dwelling unit or 900 square
    feet, whichever is less.
    Accessory dwelling units shall be located to the rear of the principal building
    and shall meet the same yard requirements (i.e. side and rear yards) as the
    principal building.
    It shall be demonstrated that one additional parking space per bedroom of an
    accessory dwelling unit shall be provided, in addition to those required under
    Section 13.4 of this Ordinance, prior to issuance of a zoning permit.
    In no case shall a manufactured housing unit or recreational vehicle be used as
    an accessory dwelling unit
  2. mp25

    mp25 Registered User

    Jun 2, 2016
    Likes Received:
    The zoning ordinance should have a chapter titled definitions. Look for the word Floor Area there, to see how it is measured. Each city can have slight variations in how it is measured.

    1.Typically, heated or cooled space is irrelevant - it all counts
    The garage is sometimes exempt from the floor area calculations - sometimes its included.
    2. The second floor would normally be added. Sometimes the basement is not added - if it meets certain requirements. Again - this depends on how the zoning is written.
    3. Maybe. There might be height restrictions that could prevent you from doing this or other regulations.
    4. The possible consequences in the future?

    Ultimately, a thorough zoning analysis should be performed by a qualified person i.e. an architect or create a site plan with some thought out details and see if you can meet with the zoning reviewer or submit to the zoning reviewer for a preliminary determination of compliance.

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