This has become an increasing hot topic in terms of number of homes, guest home requirements, and so forth. It’s important to remember that City Zoning AND Subdivision CC&Rs take precedence, so this is to outline County requirements to provide baseline. The purpose of this article is to provide an overview of what can be done on a RESIDENTIALLY zoned property within the County limits. Properties zoned commercial, industrial or multi-family (which are rare by comparison) have different regulations, as do properties within City limits. This does not cover all of the County restrictions, only answers to some frequently asked questions, and should be independently verified.

WHAT can I build?
In a nutshell, the County allows the construction of ONE primary home, ONE guest home, and any number of outbuildings such as a shed or barn, so long as they conform to the setback and size requirements.

Manufactured? Modular?
Manufactured homes, except those built prior to 1976 are allowed as long as they are constructed to satisfy the uniform building code (UBC). Modular homes are also subject to the building codes.

Do I need a building permit?
You need a building permit for any structure over 200 SqFt unless it is a dwelling, in which case a permit will be required for any size.

What are the building code requirements?
As of the time of this writing, Teton County IDAHO is operating under the 2012 International Building Code (IBC) & the 2012 International Residential Code (IRC) for determining and enforcing the quality of construction, while Teton County WYOMING has mostly adopted the 2015 versions of the code.

Size and setback requirements?
Size:Height: 30’ (60’ for some structures, such as barns in the A20 zone)
Fence Height: 6’ (without obstructing a corner lot sight line)
***Some decks, chimneys, wells, septic tanks, etc. can in some instances come within 6’ of a property line.Currently there is no minimum or maximum restriction on home size, except for those outlined for guest homes.
Setbacks (for building only, not septic or well):Front: 30’
Rear: 40’
Side: 30’
Teton River: 100’
Stream or Creek: 50’
Irrigation Ditch: 15’
Accessory buildings such as sheds under 200 SqFt can be as close as 12’ to a property boundary.

An article regarding septic installation and setback requirements can be found here.

Guest homes?
ONE guest dwelling can be constructed (attached or detached) to the primary unit and must have it’s own kitchen, bathroom and bedroom. The maximum size must not exceed 50% of the primary dwelling square footage or 900 SqFt, whichever is GREATER, not to exceed a total of 1500 SqFt. If the parcel is 5 acres or larger, these size requirements shall not apply. On acreages smaller than 1 acre, guest dwelling are not allowed.

How many homes can I build?
TWO dwellings are allowed per parcel, unless the parcel is smaller than one acre, in which case ONE dwelling is allowed.

Trailers? Campers?
Storing your OWN utility or livestock trailers is not restricted, though vehicle storage for a fee or a business is only allowed in industrial zones. RV or camper storage is restricted to ONE per property, and questions regarding occupying or residing in an RV or camper on your property (either short-term or long-term) should be directed to Teton County. Camping is not restricted on your property unless you are charging a fee, in which case a permit would be required.

Sheds & outbuildings?
Accessory buildings are allowed and cannot exceed 3000 SqFt and 2 stories in height, this applies for all types of zoning. Accessory buildings are not to be confused with accessory DWELLINGS and CANNOT be occupied as a residence.

Business or lodging operation?
Properties that are in residential zones can operate under approved conditional use permits.

An article regarding Conditional Use Permits can be found here.

Well, septic, power, phone required?
Wells are not required. An approved wastewater system such as a septic system is required for any dwelling, and must be approved with the Eastern Idaho Public Health Department.

An article regarding septic systems can be found here.

Summary
As mentioned above, this article is only a loose guideline, and questions should always be directed to the County, City and Homeowners Associations. There are other county-wide restrictions that must be considered as well, from lighting restrictions and requirements to parking an driveway requirements for fire department access. It is also important to remember that there are specific requirements when building in areas with hillsides, wetland, floodplain, or specific overlays such as zoning overlays and even wildlife overlays.

As a final note, these comments are based on Title 8 of the Teton County, Idaho Zoning Ordinance, amended May 26, 2009. The county is currently considering a revamp or rewrite of this ordinance to clarify certain points, and potentially make changes. A link to the current code can be found here. If this link is broken, it is likely that this code has been amended.