Accessory Dwellings

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Billy Hines’ ADU: Modernizing the Carriage House

Billy Hines' Carriage House in Snow

Billy Hines’ Carriage House in Snow

Quick Facts

  • Setting: urban
  • Neighborhood: Alberta Arts District, Portland, OR
  • Type: carriage house conversion
  • Use: long-term rental
  • Square Footage: 450
  • Year Accessory Structure Built: 1912
  • Year Converted to ADU: 2006
  • Owner: Billy Hines
  • Designer: Jeff Brown
  • Builder: Hard Line Design & Construction
  • Total Cost: $60,000

“I always knew my carriage house could be a living unit. You just look at it and see that someone could live there.” – Billy Hines

Billy Hines' Carriage House Before

Billy Hines’ Carriage House Before

The first time Billy Hines saw his three bedroom house in Portland’s Alberta Arts District, he decided that someday he’d make the old carriage house into a living space. He bought the house in 1995 and began slowly renovating it. In 2006 he went through the process of converting the existing accessory structure into a permitted Accessory Dwelling Unit. The 500 square foot carriage house, originally constructed in 1912, had large sliding doors and plenty of character. Billy’s plan was to transform it into a 450 square foot ADU with one bedroom and one bath.

“One unique thing about me is that I’m just an average Joe who works in the restaurant industry. I’ve done a lot to my house on a pauper’s budget. I knew I wouldn’t be able to get much financing. I wasn’t going to qualify for another loan, so I took out a second mortgage. Getting the loan was easy. Getting the city to approve it was the hard part. I have a story of maddening government red tape I had to navigate through to get the permits and plans approved.” -Billy Hines

Billy brought his friend Jeff Brown on board to help him with the architectural drawings. Frustratingly, Billy’s plans were rejected the first two times he and Jeff put them forward.

“We’d get the plans drawn up and take them downtown to the office and the reviewer would stamp it denied.” -Billy Hines

The first reason the plans were rejected was was that in Portland, OR the design guidelines for a detached ADU require the the roof to match the primary structure. The original carriage house had a flat roof and Billy’s budget wouldn’t allow him to put a new pitched roof on his ADU. (The current regulation provides exceptions to the design guidelines for existing accessory structures such as garages and carriage houses.)

Billy Hines' Carriage House Before

Billy Hines’ Carriage House Before

“When this house was built that law [requiring an accessory structure to match the primary dwelling] wasn’t on the books. So we challenged it. The house was built before the law so they gave us the exemption.” -Billy Hines

The second major hurdle was the requirement in place at the time that an ADU be no larger than 1/3 the size of the primary dwelling. (The current regulation is that an ADU in Portland can be up to 75% of the square footage of the primary dwelling or up to 800 square feet, whichever is less.)

“We took the square footage of the house and the carriage house and the formula is that the carriage house can be no bigger than 1/3 of the main house. The ADU was 1 ½ feet bigger than the 1/3. So we asked for a variance.” -Billy Hines

Billy Hines' Carriage House After

Billy Hines’ Carriage House After

The variance request triggered a design review hearing, which cost an additional $600. Notification was sent to all neighbors within 200 square feet and none of them objected to Billy’s carriage house to ADU conversion. For Billy, the high point of his ADU permitting process was when a representative from the Portland Development Commission gave him hope that his project was worthwhile. She told him that she’d heard about his project and at the design review hearing she spoke up in support of Billy’s effort to convert a historic carriage house into an apartment. Nevertheless, it took 8 months for Billy and Jeff to get the plans approved.

“If I did not have Jeff helping me do this, I could not have done this. I’d wanted to quit many times, but Jeff offered to do the third set of plans for free. At first I thought it was a big hill to climb, but once I got reassurance we went through and later that summer we were building.” -Billy Hines

Billy found a small design-build company, Hard Line Design & Construction, who could meet his $60,000 budget for the renovation. However, Billy had not anticipated that the permit fees would amount to $8,700 nor that appliances would run him an additional $2,000 so he ended up putting this expense on his credit card.

Once it was complete, Billy moved into the ADU and lived in it himself. He recently moved back into his 3 bedroom house to provide more space for his new dog. He is currently renting his ADU to a tenant. Billy has a good sense of how the space works for a tenant since he has lived in the ADU himself.

Billy Hines' Carriage House Landscaped

Billy Hines’ Carriage House Landscaped

“It’s a cozy home for one person without lots of hobbies. It’s like a cabin. It’s quiet. There’s pond with a four tier water fountain trickling outside the bedroom window. I think it’s just a gorgeous little spot. I now use the E-word for my property. It’s an estate. There are multiple buildings here.” -Billy Hines

Now that the permitting process is behind him, Billy can’t think of any drawbacks to having an ADU. In fact, he thinks an ADU is a good option for anyone who can figure out how to have one of his or her own.

“It’s a good idea to have a carriage house. Say your marriage goes wrong. If your grandmother or mother-in-law wants to come stay with you. I’d like to retire back there, rent out my larger house and maximize my income in my older years. A three bedroom house and social security should be enough.” -Billy Hines

So what’s Billy’s advice for homeowners considering creating an ADU on their property?

“Save your money, get your credit together, and be prepared to get turned down and keep trying until you get it. You may not get it the first time.” -Billy Hines

About linamenard

Hi. My name is Lina Menard and I'm a small house dweller, designer, blogger, and builder. I'm currently collecting ADU Case Studies for Through my company Niche Consulting LLC, I help people design and build the home (and life) of their dreams! I also tell my stories about simple living in small spaces - like a travel trailer, a yurt, a backyard cottage, and tiny houses on wheels - at Niche News.

5 comments on “Billy Hines’ ADU: Modernizing the Carriage House

  1. Martin
    December 18, 2014

    Simply stunning,

  2. Carolyn
    December 18, 2014

    Perfect for a mother-in-law suite, my husband won’t be pleased at the price, but I’m sure the benefits will outweigh the cost. 🙂

    • linamenard
      December 20, 2014

      Dear Carolyn,

      ADUs, like standard homes, vary considerably in cost. Converting an existing space such as a basement, garage, or in Billy’s case a carriage house, often has hidden costs as you tear open walls and learn more about the structure. However, existing spaces often have charm and history, like Billy’s carriage house does. Best of luck as you weigh the pros and cons of doing a conversion. Be sure to check out the other garage conversion case studies on

  3. Martin John Brown
    December 21, 2014

    Thanks for the story, Billy. I think there is a lot that other people can learn from this one.

    First, a carriage house or double garage is a PERFECT conversion candidate for a relatively “accessible” small house because the place has a floor that is already level with the approaching driveway or yard.

    Second, there are bound to be roadblocks in the process, but if the project makes economic sense, it is worth battling through them. I feel for Billy because I was doing my own ADU around the same time and had similar fights with the city. For a first-time homeowner-developer, dealing with the inconsistency of city officials can leave one feeling utterly vulnerable and powerless — one official will approve something, another in the same office will deny that exact same thing, and some will be using outdated or imaginary rules. I’m not exaggerating — all these things happen.

    Development pros have figured out strategies for dealing with this inconsistency, but the first time homeowner-developer is a babe in the woods. Especially when you consider the homeowner-developer is typically risking a lot of their own money when they develop an ADU, it is a very high stakes scenario. It is no wonder a lot of people seem to give up. Anyone who believes ADUs are a “good thing” needs to take the unique inexperience of homeowner-developers into account.

    However, if the homeowner-developer can get through the process, an ADU can indeed be rewarding. It gives a lot of flexibility for lifestyle changes and income generation — growing family, shrinking family, old age, etc. Congrats to Billy for making it work!

  4. Martin
    January 13, 2015

    This is the coolest thing. Will be looking into this further. Thanks.

Comments are closed.


This entry was posted on December 17, 2014 by in 400-599 SF, Case Study, Conversion, Detached, Garage, Projects and tagged , , , , .
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