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Tiny Houses and RVs To Be Allowed as Housing in Portland

On April 28th, 2021, Portland’s City Council unanimously passed a new set of regulations that allows for recreational vehicles (RVs) and tiny houses on wheels (THOWs) to be used as a legal, viable housing option on residential properties in the City of Portland beginning on August 1st, 2021.  

This post is intended to synthesize these new regulations in plain language and provide some context about the policy basis of this change.

We’ll start by covering the new regulations. Then, I’ll cover the policy import and context for this new set of regulations. And lastly, I’ll share perspective on the advocacy work that went into the passage of these regulations for other housing advocates who may wish to follow suit.  

New Regulations for THOWs and RVs

Here’s a plain language interpretation of the new regulations.

  • One RV/THOW may be used on any single family residential property as a legal housing option
  • No RV/THOW certifications or inspections are required
  • If the RV/THOW has internal plumbing, the site must have a permitted RV sewer dump (similar to a sewer cleanout) and a water connection
  • There must be a permitted electrical hookup for the RV/THOW
  • The RV/THOW must be parked behind the front architectural plane of the primary dwelling on paved or unpaved surfaces

For the city’s official standards, refer to this page (which reflects the current/old standards). The new standards haven’t been posted yet, but you can find the draft amendment language here (p.42-43). 

Policy Background

ADUs are commonly viewed by policy makers as a potential way to create affordable housing. While this may be partially true, they don’t fit squarely within the affordable housing category. And with the exception of structural conversions and some prefab ADUs, most new construction ADUs are quite expensive. In Vancouver BC and the Bay Area for example, detached custom ADUs may cost $400K.

So, while it’s politically convenient to frame ADUs as affordable housing, a more nuanced understanding of the market is required to accurately describe how ADUs do and do not fit in as “affordable housing”

Conversely, RVs and THOWs are affordable. In any major city in the country, you’ll be able to find used RVs and THOWs for sale for under $20K

But, just like ADUs have historically suffered from the lack of viable zoning framework for their flourishment, so too RVs and THOWs suffer from a zoning framework that has prevented them from being effectively used as a low cost housing solution. They’re essentially banned as housing options almost everywhere by zoning regulations.  

In fact, the only places where people can legally live in an RV tend are in RV parks and mobile home parks. And these can only be built on commercially zoned parcels. Furthermore, since RV and mobile home parks typically require large amounts of space to accommodate RV navigational needs, they commonly don’t pencil out in areas in the country where there’s an affordable housing crisis; Large, commercially zoned parcels simply cost far too much. This is why you can’t find many RV parks in high cost cities (ie. most major coastal cities in the United States). And, this is why, practically speaking, zoning effectively bans legally living in RVs–there’s simply nowhere to legally park and live in them.

However, estimates indicate 500K to 1M people actually do live in RVs full time nationally. Indeed, RV parks are quite common in small and rural towns where land is less expensive, but you may have a difficult time finding any vacant spaces at RV parks in New York City, San Francisco, Seattle, or Portland. 

An RV park located in small town in New Mexico

There’s a glaring mismatch between the economic need for legal spaces to park and live in RVs, and zoning regulations for the habitation of RVs in major US cities.

Meanwhile, residential properties in all major cities have suitable locations for parking and living in RVs. 

What’s even more glaring is that RVs/THOWs are already allowed to be parked on residential properties. It’s simply that the zoning code hasn’t considered allowing them for habitation. It’s a solution that’s been sitting under our noses that just hasn’t dawned on most policy makers – RVs/THOWs might just provide a novel housing solution to address the affordable housing crisis.

If the policy objective is actually to provide more affordable housing options, RVs/THOWs on residential properties provide a very flexible, innovative, market-based housing approach to help address the affordable housing shortage, vastly exceeding other housing types in terms of providing rapid, flexible, low cost housing.

Rapid technological and design advancements in RVs/THOWs allow them to be quite nice for full time habitation. Even so, admittedly, living in RVs/THOWs is only going to work for a limited subset of the population. Let’s assume that only 10% of the population would consider living full time in an RV/THOW in a nice residential setting.

The thing is, that’s a LOT of people potentially getting their housing needs met. 

For those who are keen on learning how to set up a residential property to host an RV/THOW, here’s a post in which I cover how to install the infrastructure for an RV/THOW on a residential property for about $5K

Advocacy to Pass These Regulations

Since October, 2017, the enforcement of the provision that does not allow the habitation of RVs and THOWs on residential properties have explicitly been deprioritized. This was a policy measure that the city council member in charge of the Bureau of Development Services at the time made in response to a call for this change from a local church group. This deprioritization measure was taken under the policy umbrella of a “housing emergency”, which is a formal declaration that the Portland’s mayor in 2015 called which allows city departments to waive certain portions of the zoning and building codes to address the housing crisis. 

In 2020, the City decided to work on permanently codifying a set of development regulations that had been treated as temporary zoning measures under the housing emergency declaration. Codifying the changes into law would allow for the City to possibly “end” the formal housing emergency declaration, since the current housing crisis is (unfortunately) the new normal. 

This project was called the Shelter to Housing Continuum Project, and was scoped to address a variety of low cost housing zoning topics, including flexible household living arrangements, SROs, and outdoor shelters. In the early stages of the public input process, housing advocates pointed out that the Shelter to Housing Continuum Project was also the appropriate regulatory project framework to include provisions to allow for THOWs/RVs on residential properties.

It was notable that in the 5 years since the deprioritization was in effect, there was very little, if any, public backlash about this policy. And my own informal research indicated that RVs/THOWs were already playing a substantial role in providing housing in Portland.

My research surprisingly found that there were more inhabited mobile dwellings in my Portland neighborhood than there were permitted ADUs.

City staff thankfully bowed to this suggestion from advocates and the planning commission, and included draft provisions for RVs/THOWs in the project. The initial draft provisions required the:

  • RVs/THOWs to be registered with the DMV
  • RVs/THOWs to be certified as Park Model RVs
  • RVs/THOWs to be connected to sewer
  • RVs/THOWs be classified as an ADU

Advocates successfully pushed back against these standards using the following logic:

  • Since the vast majority of THOWs aren’t built to park model RV standards (ANSI A119.5 standards), we’d be displacing many residents if the City suddenly required that THOWs meet these standards.
  • The DMV doesn’t require RVs to be registered unless they’re being used on public rights of way. So, this requirement wasn’t especially relevant since the RVs/THOWs were going be used as housing on private property and when needed, temporary trip permits are simple enough to obtain from the DMV
  • Not all THOWs/RVs need to have sewer connections, since some of them don’t have internal plumbing. The occupants may use the bathroom in the primary house. This is the same standard that the City would use for a detached bedroom without a bathroom.
  • Lastly, since THOWs/RVs are vastly less expensive and quite different than an ADU (RVs are mobile, after all), they shouldn’t be classified as one. Since we want to embrace this housing type, rather than discourage it, we shouldn’t allocate the THOW/RV against the allowable ADU entitlement. By NOT classifying RVs/THOWs as an ADU, this bonus entitlement is conveyed to all residential properties, including middle housing (such as triplexes and quadplexes), not just single family homes.

In the four public hearings about these provisions (which I watched like a hawk), I made another notable observation:

Of the 2,616 public comments and hundreds of verbal testimonies, there were almost no critics of this particular proposal. In fact, there was seemingly unanimous public support for legalization of habitation of RVs/THOWs on residential properties. 

Is unanimous public support for anything even possible these days? Was this just a “Weird Portland” fluke?

In any case, I’ll confess that this observation was shocking to me, and made me realize that not only could a significantly liberalized approach toward the habitation of THOWs/RVs on residential properties incrementally help solve the affordable housing crisis in other cities, but perhaps they can do so with fairly broad public support. And quickly. 

Put a wheel on it.

About Kol Peterson

Kol is an ADU consultant, advocate and author of Backdoor Revolution: The Definitive Guide to ADU Development. Read more here: and learn about building your own at Email at

8 comments on “Tiny Houses and RVs To Be Allowed as Housing in Portland

  1. emily
    May 1, 2021

    When I first read this headline I thought it was saying that THOWs and RVs would be able to be parked on vacant lots. And I was so happy! And even though I’m still pumped about this recent development, I’m wondering what your take is on the possibility of vacant lots being allowed to host THOWS and RVs someday? I am an owner of an oversized vacant lot and desire so badly to put a bunch of THOWs on there and provide housing to as many people as I can. I get approached weekly by Tiny House owners about parking their house there. I would happily provide all of the infrastructure needed. Because that would be a fraction of the cost of actually building a handful of small houses (my other idea) but would provide the same number of housing units! I work in construction and I’m wondering if developers would think twice about building a McMansion if they could instead build multiple THOWs and sell the entire development as an investment property. The potential upside to allowing multiple THOWs on vacant lots is huge. You see so many vacant lots just sitting there attracting garbage and inviting non-authorized inhabitants, which upsets neighbors and accrues nuisance violations. Vacant lots are going to waste all over town when they could be going toward the public good of providing affordable, quick housing. And Tiny House villages are cute and fun!

    • Kol Peterson
      May 3, 2021


      Good point!

      Unfortunately, the current regulations won’t allow the THOW to be the *only* dwelling. The regulations read that the THOW needs to be on a site with a “house, attached house, or manufactured home”.

      The regs also won’t allow groups of THOWs on a residential property, which is something advocates pushed for. There’s still hope that clusters of THOWs could be allowed under RIP2, which is a new process the City is undertaking to develop codes for cottage clusters in residential zones in the City of Portland, in accordance with state house bill 2001 (“HB 2001”).

    • Pat
      May 3, 2021

      ” I’m wondering if developers would think twice about building a McMansion if they could instead build multiple THOWs and sell the entire development as an investment property. ”

      Turning affordable housing into investment properties is the root of the current affordable housing problem in Portland. Investors(many from Hedge Funds, and/or International Investors) come in and buy up affordable housing in cash, making it impossible for citizens to buy starter homes. These investors become massive slum lords once they own the property, refusing to repair their properties or do routine maintenance. They will never fail to increase rent when ever possible, and renters, good luck at ever seeing your deposit back, no matter how gently you used the unit. Those units will no longer be affordable, if they are sold as an investment property, because the new buyer will want profits from their investment. If you build this vacant lot for tiny homes, and sell it to investors, there is a real likelihood that the investor will either raise rents too high to be affordable, giving an excuse to use the lot for McMansions, or they will day 1 bulldoze the lot and put up high end condos or apartments asap.

      If you build this lot, and work with a local housing advocate organization for them to buy the lot, giving them time to organize grants, or a similar plan, then that would be wonderful and really help increase affordable housing. Currently the investment housing market is the cause of Portland’s housing crisis.

      One other note, one reason a single tiny home in people’s yards doesn’t trigger a NIMBY response is because it’s only one unit and with the home owner onsite, it assures neighbors that the situation is being looked after. If a multi unit site is built and sold to an investor who is an absent landlord, that becomes a recipe for problems the investor, neighbors, and the city doesn’t want. Making it more likely the investor will just bulldoze the property and put up condos.

  2. Amy L Turnbull
    May 3, 2021

    Bravo, weird Portland! With so much news about demolitions and displacement in Portland (i.e. The Tiny House Hotel and my favorite food truck on Alberta with the best grilled cheese ever) I, too, am surprised that there wasn’t any pushback! Take that, capitalism! I spent a summer in SE in my teardrop parked on “the down low,” no bathroom but access to the main house: I got cheap digs ($500 for a month) and my friend got help paying the rent. Nothing was demolished, no one was displaced, no second mortgage was generated to finance an ADU. Gone are the extension cords draped across sidewalks, thankfully (yes, it’s true!). Now movable tiny houses can co-exist safely and legally in residential spaces. I mean, they are there already, let’s face it. But now they are legit! Again, bravo!

  3. David Donahue
    October 7, 2021

    Does anyone knows if a THOW built to the RV codes for occasional (non-permanent) occupation is seen by a homeowners insurance company if it is used for a fully time renter or family member who may be living their permanently rent free?
    I’m concerned because none of the Title 24 (stick built) or Title 25 (manufactured) codes are followed. Thank you in advance.

  4. Melissa Cunningham
    May 6, 2022

    Hi Kol, I’m in PDX and living in my house on a property. I want to install an rv hook up in the yard and have someone pay to rent my ‘slip space’ for their tiny house. I’m calling around insurance companies and am having trouble finding anyone that will cover me as a ‘slip landlord’. They all say that I need to own and provide the tiny house/rv in order to be fully covered (and I’d need 2 policies one for main house and one for tiny house). Any knowledge appreciated on just being the slip provider w/r/t insurance. Thanks (spoiler American Family and American Modern already said no). Thanks so much for all that you’ve done in Portland for ADU and tiny homes!!!
    Cheers, Mel

    • Kol Peterson
      May 6, 2022

      Mel, good question. Personally, I haven’t bothered trying to find insurance to host a THOW, but I’m generally a bit rogue and edgy 🙂 I just posted it your question here: You can follow that group and see what responses come through on that forum.

Comments are closed.


This entry was posted on April 28, 2021 by in News, Policy & Trends and tagged , .
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