In the state of Oregon, permanent tiny homes can be built as detached single-family dwellings or as accessory dwelling units in areas destined for residential use, while mobile tiny homes can be sited in RV parks. However, Oregon municipalities have controlling power, so you should check zoning laws and local building codes before proceeding.

Oregon is a great state to live in. However, accommodation in the state can be a problem, especially if you are not financially robust.

Thankfully, small dwellings like tiny homes provide affordable housing opportunities compared to other dwelling types. The tiny homes make it possible for those who need to downsize to acquire inexpensive, decent, safe, and sanitary housing in the state.

But before building a tiny house in Oregon, you must familiarize yourself with applicable rules and regulations. This is imperative because if your tiny house is non-compliant, you may receive heavy fines and can even be evicted from the home.

In this article, we’ll discuss the rules and regulations that apply to all categories of tiny houses in Oregon.

At the end of the article, you’ll know:

• What counties of Oregon allow tiny houses
• How tiny the tiny homes can be in Oregon
• The regulations that apply to the different categories of tiny homes in Oregon
• Where you can place tiny houses in Oregon.

What Oregon counties allow tiny houses?

Oregon is among the most progressive states when it comes to embracing the housing revolution called tiny homes.

Tiny homes are allowed all across Oregon, especially in the big counties. For example, the tiny homes statute provides that an Oregon city with a population of 2,500+ or a county with a population of 15,000+ must allow for the development of at least one permanent tiny home as an accessory dwelling unit. 

This stipulation covers most of Oregon's cities and counties.

That said, the regulations for developing tiny homes vary from county to county. If you are planning to build a tiny home in Oregon, you and your developer should work with municipalities to ensure that your tiny home will be legally sited and occupied.

One of the worst things that can happen if you’ve built a tiny home (especially one with a permanent foundation) is to be evicted because tiny homes are not allowed in the area. Thus, before sitting a tiny house anywhere in Oregon, check if such small dwellings are permitted in the area.

How tiny can a house be in Oregon?

The Oregon Small Home Specialty Code (OSHSC) defines a small house as a single-family residence that is not more than 400 square feet in size. No minimum size is specified by the applicable regulations. 

According to the OSHSC statute, which is the recognized construction standard for tiny houses in the state, any dwelling in Oregon that exceeds 400 square feet will not be considered as a tiny house. 

The statute’s definition of a tiny house is not different from that spelled out in the Oregon Reach Code (Part II), which the OSHSC replaced. The Reach Code had defined a tiny house as a dwelling that is 400 square feet or less in floor area.

Rules and regulations for tiny homes

Tiny homes are generally categorized into three categories:

• Permanent tiny homes
• Temporary tiny homes
• Transitional structures

Because these tiny homes are very different, distinct regulations apply to their development.

Rules for permanent structures

A permanent tiny home is defined as a structure attached to an approved foundation. It prioritizes energy efficiency and the safety of occupants at the expense of mobility. 

Permanent tiny homes in Oregon must be built to federal standards or the building code of the state. However, the regulatory models for permanent tiny homes in Oregon are well established. So, this may be the easiest path for people wishing to site and live in tiny homes in Oregon.

Some of the building codes are:

Oregon Residential Specialty Code (ORSC) 

Some of the provisions of this code are:

• Tiny homes under 600 square feet can have one sleeping loft, with a ladder used as a means of access to the sleeping loft;
• Every tiny home with a sleeping loft must have an automatic fire sprinkler system;
• The local building inspection program must provide plan reviews, permits, and inspection requirements for every tiny home in the state;
• Builders, electricians, and plumbers who’ll work on the tiny home must be licensed by the state.

Oregon Small Home Specialty Code (OSHSC)

The OSHSC code allows single-family tiny homes up to 400 square feet to be built to the ORSC code, with sleeping lofts accessible by ladders, as long as the structure has an approved fire protection system.

The OSHSC tiny homes are also subject to the same plan review, permits, and inspection requirements as the ORSC tiny homes. 

US Department of Housing and Urban Development (HUD) Manufactured Home Construction and Safety Standards

This code allows manufacturers to seek permission from the HUD to pursue innovative designs in tiny home construction.

However, before building, the manufacturers' designs must be certified by a federally approved inspection agency. All installers must be certified by the state, and the tiny home must have a local permit. 

Rules for temporary tiny houses

A temporary tiny home is one that is attached to a frame or chassis, which may or may not have wheels.

Temporary tiny homes are usually not permanently affixed to land, except those located in a mobile home park. Rather, they prioritize mobility. They also make good use of space-saving features like sleeping lofts.  

From January 1, 2020, the state no longer regulates the construction of temporary dwellings, including tiny homes. You’ll have to check with your municipality to ensure that your tiny home can be legally sited.

Mobile tiny homes which are designed to move regularly on public highways are subject to the Federal Motor Vehicle Safety Standards developed by the NHTSA (National Highway Traffic Safety Administration). The standards include those for wheels, tires, brakes, rear impact guards, lights, and VIN numbers.

Oregon also limits the width of mobile tiny homes. They should not be wider than eight and one-half feet. (8.5 feet wide)

For RV (Recreational Vehicle) tiny homes, the Oregon Department of Transportation (ODOT) provides certificates of title and registration. This also applies to PMRV (Park Model Recreational Vehicle) tiny homes.

Temporary tiny homes that are not designed for regular movement can be transported. But you’ll need a trip permit or an over-dimension permit. 

Rules for transitional structures

The transitional tiny homes are structures that municipalities can set up within their urban growth boundary to provide seasonal or emergency living facilities for homeless people who do not qualify for low-income housing. These usually include cabins, yurts, fabric structures, and similar accommodation.  

The transitional housing units are established and regulated at the municipal/ local government level.

Where can I place a tiny house in Oregon?

Where you can place a tiny home in Oregon depends on the type of tiny home and the local zoning codes specifying the legal use of the land in the area.

Talking of the type of tiny home, Oregon treats the different tiny homes differently. As such, there are places where you can site a "tiny home with a permanent foundation" but cannot site a "tiny home on wheels." 

Talking of zoning codes, in Oregon, land use is controlled by the local government through land use regulations that are codified in zoning ordinances. 

That is, lands are zoned for different uses. For example, some areas may be zoned as EFU (exclusive farming use), others for commercial use, and others for residential use. This means that you'll be able to site a tiny home only in areas that are zoned for tiny homes development or use.

Siting permanent tiny homes

Permanent tiny homes can generally be sited on lands zoned for single-family residential use.

The tiny homes statutes have it that:

• Tiny homes built to the ORSC standards are detached single-family dwellings and can be constructed on land zoned for that purpose. (ADU)
• Cities and counties must allow the siting of HUD standard tiny homes on all lands zoned for single-family residential use within the urban growth boundary.

Permanent tiny homes are the best route to having small dwellings in Oregon. This is because you can have them not only as detached single-family dwelling but also as an accessory dwelling unit (ADU).

The accessory dwelling units (ADU) are small buildings that can be sited in the backyard of a single-family building. 

Regulations regarding accessory dwelling units (ADU) now allow the citing of a tiny home in the backyard of another building. Many Oregon cities and counties (cities with population of over 2,500 and counties with population of over 15,000) must allow for the development of at least one ADU for each detached single-family dwelling within their urban growth boundary. 

In cities with a population of 25,000 or more, permanent tiny homes can also be built as cottage clusters on land zoned for residential use within the urban growth boundary. A cottage cluster is a group of 4 or more detached housing units not larger than 900 square feet that share a common courtyard.

Siting temporary tiny homes

In Oregon, temporary tiny homes can always be sited at manufactured dwelling, mobile home and RV parks where they are legally connected to utilities.

Outside of these parks, you'll have to refer to your municipality for exactly where and how long you can site a temporary tiny home.

Siting a transitional tiny home

The transitional structures are sited within the urban growth boundary of a municipality. However, individuals cannot set up these structures.

They are part of local government initiatives to some seasonal or emergency  homeless persons. So, the local government determines where and how long these will stay.

Conclusion

Tiny houses are very popular in Oregon. Also, Oregon has established regulations regarding the development of these small dwellings. 

The permanent tiny homes offer the easiest path to legally owning and occupying these small dwellings in the state. They can be sited as single-family residences or as accessory dwelling units on land zoned for their use.

However, the mobile tiny homes have more restrictive regulations regarding both their development and siting. The state regards mobile tiny homes as recreational vehicles. As such, they are subject to the Federal Motor Vehicle Safety Standards adopted by the NHTSA, and they can only be sited at RV parks, except directed otherwise by municipalities.

Thus, before building or siting a tiny house in Oregon, it is wise to check with local zoning laws as well as the building codes pertaining to their development.

If you need help understanding zoning codes, building regulations or anything else, TinyHouse is here for you. 

TinyHouse is a destination for all your tiny homes needs. Whether you need consultation services, a community of tiny home lovers, decor ideas and items for your tiny home, or events with tiny home experts, we got you covered.

Contact us today to downsize right.

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