9-3-11: ACCESSORY DWELLING UNIT(S) AND TINY HOME ON WHEELS:
The purpose of the accessory dwelling unit and Tiny Home on Wheels regulations is to define an accessory dwelling unit and Tiny Home on Wheels; address under what circumstances it is appropriate to allow increased density on a lot; and address the impacts an accessory dwelling unit or Tiny Home on Wheels may have on the surrounding area such as sanitation, increased traffic and compatibility with the neighborhood.
A conditional use permit obtained from the commission or hearing examiner may be required for an accessory dwelling unit or Tiny Home on Wheels as required below in sections 9-3-11A1, A2 and A4. Notice and hearing procedures contained in chapter 25 of this title shall be followed. The application shall be subject to the provisions contained herein and the standards of evaluation contained in subsections 9-25-3A3 and A4 of this title.
Tiny Home on Wheels shall be regulated in the same way as Accessory Dwelling Units and are subject to the standards herein except where specifically noted.
A. Standards: The following standards shall be met prior to issuance of a building permit for an accessory dwelling unit or a zoning review for a Tiny Home on Wheels:
1. On lots of less than one acre in size and on an Idaho Department of Environmental Quality regulated community water system or municipal water system, where allowed by South Central Public Health District (a variance from South Central Public Health District may be required) and with a will-serve letter from the Certified Water Operator for the system, one accessory dwelling unit or one Tiny Home on Wheels may be allowed under a conditional use permit.
2. On lots of one acre to less than two (2) acres in size, where allowed by South Central Public Health District (a variance from South Central Public Health District may be required), one accessory dwelling unit or one Tiny Home on Wheels may be allowed under a conditional use permit.
3. On lots of two (2) acres to less than five (5) acres in size, one accessory dwelling unit or one Tiny Home on Wheels shall be a permitted use.
4. On lots of five (5) acres or greater in size:
a. One accessory dwelling unit or one Tiny Home on Wheels shall be a permitted use.
b. A second accessory dwelling unit or second Tiny Home on Wheels may be allowed under a conditional use permit.
B. Restrictions: All accessory dwelling unit(s):
1. Shall be limited to a maximum one thousand two hundred (1,200) square foot floor area. Said floor area shall be the total of all floor areas as measured from the exterior face of the exterior walls. ADU garage space up to an additional one thousand two hundred (1,200) square feet is allowed. ADU’s that have floor area of four hundred (400) square feet or less shall use requirements in International Residential Code, Appendix Q – Tiny Houses.
a. The area encompassing the mechanical system shall be included in the square footage calculation. If the mechanical equipment is located in the crawl space or the ADU garage, it shall be exempt from the square footage calculation.
b. Stairs shall be excluded from the square footage calculation.
c. When an attic roof truss system creates an unusable and inaccessible attic space between the interior and exterior wall, the floor area measurement shall be taken from the outside of the interior wall;
2. Shall be allowed in the A-20, A-40, R-10, RR-40, R-5, R-21/2, R-2, R-1, R-.4, R-1/4, and RD zoning districts and shall not be allowed in any designated overlay district; except where an accessory dwelling unit is proposed in the floodplain overlay district (see subsection B3 of this section) or on property located within the CH overlay district that is not part of a CH-PUD; or within the MOD and within a platted building envelope or categorically excluded pursuant to section 9-21-4 of this title;
3. May be allowed in the floodplain overlay district as a residential use only upon approval by the commission or the hearing examiner of a conditional use permit pursuant to chapter 17 of this title and these provisions;
4. Shall meet setbacks for the zoning district in which it is located;
5. Shall require a building permit;
6. Shall be located on the same lot as the principal residential dwelling unit;
7. Shall provide for one parking space in addition to the minimum required for the principal residential dwelling unit;
8. All parking for an ADU must be contained on-site. No parking is allowed on the street.
9. Shall be prohibited on any lot less than one acre in size, regardless of the applicable zoning district, unless on an Idaho Department of Environmental Quality regulated community water system or municipal water system, has approval from South Central Public Health District and obtains a conditional use permit;
10. May be part of an accessory building containing other accessory uses, as allowed in the zoning district provided that: a) the gross floor area of the non-ADU portion of the accessory building does not exceed seventy five percent (75%) of the gross floor area of the primary residence; b) the accessory dwelling unit portion of the building satisfies all applicable regulations; c) the floor area of the accessory dwelling unit and garage associated therewith is separate and distinct from other accessory uses contained within the same building.
C. Restrictions: All Tiny Homes on Wheels:
1. The proposed moveable Tiny Home on Wheels is licensed and registered with the Idaho Transportation Department Division of Motor Vehicles.
2. The proposed moveable Tiny Home on Wheels has been certified by a third-party inspection agency ie: NOAH or other agency approved by Administrator as meeting ANSI A119.5 Standards1 , NOAH ANSI+ Standards2 and standards in Section D.
3. The Tiny Home on Wheels shall be connected to the water and wastewater system serving the primary residence, as inspected by the South Central Public Health District (wastewater) and the State of Idaho Plumbing Program (potable water connection).
4. Wheels may not be removed from the Tiny Home. Applicant/owner of the Tiny Home on Wheels shall be responsible for placement of the Tiny Home on Wheels per manufacturers specifications.
5. No exterior additions such as porches, lean-tos or sheds are permitted, with the exception of factory-fabricated porches and decks lower than eighteen inches (18″) in height.
6. Tiny Homes on Wheels shall comply with 9-3-11.B.2, 3, 4, 6, 7, 8 and 9, and 9-3-11C.1-6 to ensure standards are met. Zoning approval shall terminate in five (5) years and may be renewed if the zoning standards at that time are met. If Tiny Homes on Wheels are removed from Blaine County Code as an allowable use, no structure shall be considered legally non-conforming.
D. ANSI + Standards: All Tiny Homes on Wheels: All Tiny Homes on Wheels are required to meet the ANSI A119.5 Standards3 , NOAH ANSI+ Standards4 and the following standards listed specific to Blaine County’s climatic conditions.
1. Inspection Stages 1-5 of the most recent NOAH ANSI+ Standard Inspection Guides5 shall be certified complete and approved by NOAH and submitted to the Blaine County Zoning Department.
2. Additional requirements based on Blaine County’s climatic conditions:
a. Minimum insulation R-values: Walls R-19, floors R-20 and roof /ceiling R-28. Vapor retarders shall be in accordance with the International Residential Code.
b. Windows and doors: Shall have a maximum .30 U-factor.
c. Roof Snow Load: Shall meet the site specific requirements set forth in 7-1-3,(01), (M).
d. Skirting – Insulated skirting is required.
E. Sunset Provision: All references to Tiny Home on Wheels within 9-3-11 and 9-2-1 including all of Sections 9-3-11.C and 9-3-11.D. shall be effective from 5/17/2022 until 5/17/2027. It shall be null and void as of that date unless re-adopted by ordinance.
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