A one-stop source about accessory dwelling units, multigenerational homes, laneway houses, ADUs, granny flats, in-law units…
1) Mark Timby and Leighann Franson
2) Carissa Page
3) Megan and Matt Klepp
4) Brian Chodowski
5) Dan Batz and Anne Marie McClaran
6) Homeowners
7) Desiree Tullos and Tim Nortz
8) Carolyn Johnson
9) Pablo Chauvin
10) Robert Mercer and Jim Heuer
11) Nicholas DiStefano and Wally Schmidt
12) Michael T. Hensley and Felicity Fenton
We talked about building an ADU for three years before we started the formal process. What finally motivated us to build came down to these main reasons:
(1) Space. We live in a small, 1926 bungalow and wanted more space for our family as well as visitors. However, we’re also minimalists and believe small is better. Therefore, having two small, utilitarian houses rather than one large house suits our values and lifestyle.
(2) Equity. We have a low interest rate on our current 15-year mortgage on top of 12 years of equity in our main house. Rather than buy a bigger house and take on a bigger, longer-term mortgage, we wanted to pay off our current mortgage. We also felt, based on research and current population projections, that building an ADU would be a financially reasonable decision.
(3) Business. We’re both self-employed and needed more office space.
(4) Community. We designed the structure so that it can also be used as an open community space for teaching small workshops and gathering friends. Community is important to us. Before our ADU was even framed out, we had multiple friends, neighbors, and acquaintances ask to stay in or rent it long term. (“If you build it, they will come,” as they say.)
(5) Future. We’ve been in Portland for over 20 years and self-employed for the last 12. Our vision is to leave Portland, rent out the main house and keep the ADU for when we need to come into town to meet with clients.
Type of ADU | Detached, new construction |
Architect/Designer | Alan Armstrong, http://www.strongworkarchitecture.com |
General Contractor | Shelter Solutions, https://www.shelter-solutions.net |
Heating System | ductless mini split with Cadet heater in the bathroom. |
When did you start the design work? | 5/2015 |
When did you submit the plans to the City? | 9/2016 |
When did you start construction | 1/2017 |
When did you get your certificate of occupancy? | 8/2017 |
Total Square Footage | 515 |
Total Cost (including sweat equity) | $160K |
Cost/Square Foot | $310 |
Sweat Equity estimate (part of the “Total Cost” listed above) | It’s challenging to calculate this. While there has not been a lot of construction hands on from our part, a significant amount of time has been spent managing the project. We did salvage 100 year old doug fir 2x4s to make our window sills, Creative Woodworking NW is the place to go for this kind of thing. |
Other special project costs |
Land use adjustment ($2100) Extra long main power cable run through main house basement ($1500) |
In the coming year we plan on using the ADU for visiting friends and family as well as potentially some short term rental.
Beyond this year, we plan on using the ADU in a variety of ways. We are both self-employed so the ADU, at times, will be an office space. We also plan on using the ADU for short and medium term rental income, as well as a space for visiting friends and family. In a few years we plan on moving and will rent the main house and use the ADU personally on return trips to Portland.
The better question is: what didn’t we do? We went on multiple ADU tours, took Kol’s ADU class, talked to friends who had gone through the process as well as friends who were architects. We conducted online research and read books such as “What Your Contractor Can’t Tell You.” Eventually, we met with General Contractors and design/build firms and received four bids before selecting Shelter Solutions. Financially, we spoke with multiple banks regarding HELOC loans, but ultimately (and gratefully) were able to secure a family loan at a much lower interest rate.
Working with BDS was fairly smooth. We applied for and were granted a land use adjustment to build within 5′ of the shared property line. Due to this we also were required to perform a survey to exactly determine the property line before construction.
We view the ROI of our ADU as a flexible, ever-changing space to fit our community and financial needs. During every step of the process, we were approached by multiple friends, neighbors, and people walking by about renting the space. We know that a modest, short-term rental schedule (perhaps 10-12 days a month) will help us pay off our loan and bring us to a net-positive income, but we look forward to hosting family and friends and developing a community in and around the space. We even have visions of renting the space for small workshops or gatherings. Most importantly, we have the option to create passive income with a permitted dwelling that will continue to gain equity.
1″ rigid foam on the exterior in addition to fiberglass batts in the walls. Energy efficient Mitsubishi mini-split for heating and cooling. 3″ of spray foam in addition to blown in insulation in the ceiling cavity for a minimum of R35. LED surface mount ceiling lights as well as LED bulbs throughout the ADU. We also salvaged material from our demolished garage for the back door awning. The window sills are salvaged doug for from a friends remodel project. In case we choose to install solar planets someday, we had an empty electrical conduit laid in the utility trench while it was open rather than incurring the much higher costs of laying the pipe later.
(1) Windows/Natural Light: The first thing anyone says when they walk into the space is, “Wow, the light!” Although our space is only 515 square feet, it has 18 windows, three skylights, and three glass doors. Most of those windows and doors are south and east facing, but big, natural light fills the space at all times of the day. From our research, we noticed many ADU bathrooms tend to be in forgotten corners shoved underneath stairs, so they end up being dark and confined. We went through a few sleepless nights trying to figure out how we could fit everything in the bathroom, and still have a window (which we eventually did). We also selected a glass, bathroom pocket door, so sunlight would fill up the space from multiple angles.
(2) Architectural Angles: Since the existing structure we replaced was located on the property line, we applied for and were granted a Land Use Adjustment to build within the five-foot setback. However, at the time, the Land Use Adjustment also dictated multiple design constraints such as height of the structure. Since the stairs run along the north wall (located within the setback), we built a dormer with three skylights in order to reach the permitted height for stairs to the loft yes still limit the overall height. The result? Beautiful lines and architectural angles that fill with light and shadows and give a small, open space depth and character.
(3) ADU size-to-garden ratio: Another comment we often hear, “The space feels big for its size, but doesn’t overwhelm the backyard.” This was a conscious decision. A lot of ADUs are designed for maximum square footage (800 sq. feet). And we understand why. There are fixed costs associated with building an ADU, which don’t dramatically increase with size. So if you’re going to build an ADU, adding extra square footage could help with higher rental rates and actually bring down the cost per square foot. For us, our garden and outdoor space is an extension of our home. So we designed the ADU to be spacious, yet not take over the backyard. In fact, part of the vision is to reclaim the driveway and convert it into a private yard for the ADU and add an outdoor shower.
We are incredibly proud and grateful to have the ability and resources to design a space and bring it to life. We understand that not many people get the opportunity to build a house—no matter how small or large—in their lifetime. And it was an honor to be able to watch our vision unfold day after day. So in that way, we are most proud of the process, including our attention to care and detail (much to the chagrin of our GC, as we were probably more hands-on clients than they’re used to). We tried, to the best of our ability and finances, to make sustainable, intentional choices with materials. We salvaged and refinished fir wood from a friend’s old craftsman to use as windowsills. We reused the tin roof and wood from our demoed garage as the back awning. The kitchen and bathroom fir shelves are sourced from Salvage Works. We installed Ikea’s new line of 99% recycled kitchen cabinets. The iron kitchen brackets and cable railing are locally made and sourced. We even salvaged any unused building materials to use in the future.
A small part of any building project is letting go. Most people we have talked to say the same thing, “I see all the problems, all the inconsistencies, but most people don’t.” And it’s true. We both have discerning eyes, yet we embrace Wabi-Sabi—a crooked line here, a missed angle there. In the end, we’re happy with where we landed, but the most challenging design aspect revolved around the flooring and finishing touches. Our plans didn’t specify floor and loft materials, so an industry-standard, tongue-and-groove pine subfloor with exposed rough-cut pine beams was installed (and would now become our exposed kitchen ceiling). In the loft, this pine sub floor would be covered, but we didn’t want to cover up natural wood with a manufactured hardwood or laminate, so we scrambled to find a way to treat and preserve the pine subfloor (now the floor) and save on materials and labor cost. As of this printing, we still haven’t figured it out, but we’re not worried; we’re embracing the art of imperfection.
While we enjoyed working with our both our architect and builder, we feel the potential benefits of integrating design and construction from the beginning could be profound. There are so many design aspects that affect construction, and vise versa, that marrying these two disciplines under one roof could eliminate potential issues and create a more seamless process from beginning to end.
Also, we would choose not to build in the height of a construction boom. Luckily, Shelter Solutions has invaluable, well-established, long-term relationships with multiple subcontractors (and city inspectors) and they did a great job lining up their subs. But one missed deadline creates a domino effect, and it would be challenging to get a sub to come back to make a repair or fix during such a busy time. We often remarked, “We’re glad we hired a GC.” We also observed that construction, specifically building an ADU during a boom, is about speed and efficiency and sometimes at the sacrifice of detail. Of course, this is not new to anyone who has built a home, but for a couple of detail-oriented people, it can be another lesson in letting go.
It sounds cliché, but the time and energy we spent planning, shopping, managing, nagging, installing, finishing, etc. was much, much more than we planned. It was exhausting. Now that we are close to completion, we are ready for the project to be wrapped up. Working with good people, setting expectations, and clear communication has helped us through the process. We’re excited by how our vision has come to life.
There are many tidbits of wisdom we’ve picked up along the way. Definitely do your homework and due diligence about the team of people you are going to hire. We witnessed two of our neighbor’s home renovations go awry, so picking trustworthy, respectable architects and contractors with good communication skills is key. Go on the tours. Immerse yourself in photos and books and drawings. Stockpile design inspiration. Read the book “What Your Contractor Can’t Tell You”. Clear your schedule. Book the nanny for extra days. Start seeing a good therapist.
Also, shift your thinking from “this is a small house” to “we are building a HOUSE.” Because that’s what it is and that’s what it feels like. It might be smaller than the large houses we’re used to in the US, but you’re building a house with the added design constraints of fitting all the elements of a modern lifestyle into a small space. It’s a massive undertaking and it will test you, but in the end you will be surrounded by a vision you built.
I bought this property about a year ago with the explicit intention of converting the garage into a rental unit so I could bring down the cost of the mortgage. Over time, however, this project quickly became a labor of love. It was very time consuming, but I really enjoyed this entire process!
Type of ADU | Garage conversion |
Architect/Designer | Jacob Chavez , jchavezdesign.com |
General Contractor | Bluebird Construct LLC, portlandadu@gmail.com |
Heating System | cadet heaters |
When did you start the design work? | 10/2016 |
When did you submit the plans to the City? | 2/2017 |
When did you start construction | 2/2017 |
When did you get your certificate of occupancy? | 7/2017 |
Total Square Footage | 350 |
Total Cost (including sweat equity) | $110K |
Cost/Square Foot | $314 |
Sweat Equity estimate (part of the “Total Cost” listed above) | $5K |
Other special project costs | Connecting sewer to the house cost $7,500 plus a 2-week project delay. The main cost was $6,400. However, a shift in strategy triggered a requirement to hire an an arborist and rent fences to protect the trees. I also had to get an adjustment (which was processed as an “intake”) through the City of Portland. |
I’m planning to use it as a short-term rental, at least initially.
I imagine transitioning the ADU to a long-term rental within the next few years. And who knows what the future holds, but I also can imagine family or friends living there. I can even imagine myself living there.
I took Kol Peterson’s ADU class, I attended the ADU tour, I talked to lots of people, and I read through a lot of the resources and case studies on the accessory dwellings website. The research paid off!
Since garage conversions are permitted “over the counter,” the process was actually quite easy and the permit fees were reasonable. I was super impressed by BDS. The only hiccup was that I had to get the permit modified (when the initial strategy for connecting sewer to the house didn’t work out), and that process was processed as an “intake” rather than “over-the-counter,” which caused a stressful two week delay at the very beginning of the process. All in all, my experience was very positive.
I’m feeling pretty positive about the return on investment. The ultimate price tag was more than I thought it would be going into the process, but I’ve never looked back. This ADU feels like a safety net for me – both in terms of its income-generating potential and its flexibility for future use.
insulation – ceiling has R-38, walls have R-25; locally sourced, reclaimed materials
I’m actually thrilled with all of the “rustic-industrial”-style finishes, which include black iron edison lighting, a live-edge Doug Fir countertop, a distress-painted entry door, a bathroom vanity made from an antique sewing machine, walls/trim clad with reclaimed wood, etc, etc. As you can imagine, designing, sourcing, and procuring materials for these finishes required a lot of thought (and crafting), so I actually carved out this part of the process for myself. (And I’m glad I did, because I have a lot of ownership and pride in the ultimate outcome!)
Since the original garage was made of cinderblock, we decided to afix structural plywood panels to the interior framing (i.e., a “shear wall”) to provide additional bracing in the event of an earthquake. My GC said at one point, “This place is a bomb shelter!”
The design was scaled back to include a kitchenette rather than a full kitchen due to cost considerations, and I have to admit that I question whether this was the right decision. (This being said, it was designed such that it would not be difficult to upgrade the kitchen in the future.)
I would have hired a structural engineer during the design phase. The original design included plans to vault the ceiling and move the cross ties from 16’’ on center to 32’’ on center. The ultimate outcome was absolutely gorgeous, but it entailed some complex changes to the truss system that necessitated an engineer’s eye. We ultimately hired an engineer during the build process to ensure peace of mind.
I don’t know if I would call this “surprising,” but having a great relationship with your GC based on open, honest and transparent communication is super important. Micro-decisions were being made every single day, particularly in the final weeks. I can’t even imagine how tough this project would have been if I had not had such a great relationship with Bluebird Construction.
Thinking through the contracting strategy was arguably the most challenging part of this whole project. I struggled over whether to go with: A) a design/build firm (i.e., the same firm for both functions), or B) a phase I design firm, followed by a competitive bidding process, resulting in a phase II build firm. The challenge is that the two functions really should not totally segregated; however, design/build firms are arguably more expensive because the opportunity for competition is lost. I therefore recommend landing somewhere in the middle. That is to say, get a designer and a builder and pay them to collaborate on phase I. Then make phase II contingent on the builder providing a reasonable bid. However, make clear that the homeowner has the right to bid the design out to other firms. I also recommend going with a “fixed price” agreement rather than a “time-and-materials” or “cost-plus” agreement. (The first option puts most of the risk for cost over-runs on the contractor, while the latter options put most of the risk on the homeowner.)
We wanted a way to generate income with a rental property that we are able to offer to a friend and her son.
Type of ADU | Detached, new construction |
Architect/Designer | Original plans Brint Riggs, design changes by Ethan Whitesell |
General Contractor | Shell Contractor Benjamin Weizel SpaceKraft Construction |
Heating System | Radiant hydronic |
When did you start the design work? | 5/2015 |
When did you submit the plans to the City? | 8/2015 |
When did you start construction | 6/2016 |
When did you get your certificate of occupancy? | 1/2017 |
Total Square Footage | 799 |
Total Cost (including sweat equity) | $130k |
Cost/Square Foot | $162 |
Sweat Equity estimate (part of the “Total Cost” listed above) | $30k |
Other special project costs | The siding on the main house could not be matched. The siding on the adu had to be hand made, and cost significantly more than we planned |
Long term rental
Rental, and possible residence once kids are grown
Attended an adu class and a tour. At the class I toured and adu that the design seemed perfect. I contacted the original designer and purchased the plans. Talked with a number of contractors for bids and acquired financing.
I found working with BDS to be the hardest part of the whole project. It was very time consuming and it seemed like you would get different answers depending on the day. The stair design on the original purchased adu plans were no longer up to the Portland city code, so had to be redesigned. The adu is on an alley so required no set back, the person I submitted the plans to, did not know that. Also the city approved the plans to build over an existing gas line, which later we found out was not ok.
I think it was totally worth the cost. We should make back our investment in under 10 years, and hopefully be able to live mortgage free if we rent the front house.
As many recycled materials as could be used
I love the high ceilings and open feel. I’m really happy with the design changes made to the original plans.
The use of recycled materials in the finishes on the adu, especially the bathtub and master bedroom closet. I’m also really proud of the deals I got on the light fixtures and kitchen.
I am least happy with how the concrete patio/driveway area turned out.
I would have started on the kitchen plans much sooner to take better advantage of sales and craigslist. I would have done a better job checking references on a few of the subcontractors.
Everything took longer and cost more than we originally planned. We were
Be prepared for how long the process actually takes, and how much it will actually cost. Do your research when finding a contractor. Make sure they are someone you can work closely with. Get lots of estimates and ask questions.
At first we wanted to build a garage to replace our detached carport. When submitting for permits, BDS approached me with the idea of adding the ADU. After a discussion with my significant other about the idea of adding more living space to a already small primary interior footprint, we decided to cancel the garage permit and start the ADU process. The idea of more living space for guests to stay over, entertaining and having a showhome for our Cedar Designs/Linwood Homes dealership (www.cedardesigns.com) seemed like it would be a great fit.
Type of ADU | ADU above a garage |
Architect/Designer | Brian Chodowski |
General Contractor | Brian Chodowski/Envision NW Construction, Inc/Owner-Builder www.cedardesigns.com |
Heating System | ductless mini-split and bathroom cadet |
When did you start the design work? | 1/2014 |
When did you submit the plans to the City? | 6/2014 |
When did you start construction | 5/2015 |
When did you get your certificate of occupancy? | 9/2017 |
Total Square Footage | 400 sq ft ADU above 400 sq ft garage |
Total Cost (including sweat equity) | $128K |
Cost/Square Foot | $160 (including costs of garage in this calculation) |
Sweat Equity estimate (part of the “Total Cost” listed above) | $63K. I did the majority of the building myself. This is why the project took as long as it did. I had to work it in as I had free time and weather permitted. |
Other special project costs | I had to demo an old carport and storage unit, at a cost of $800 for demo and $2,500 of sweat equity. |
Certification & Energy Scores | Earth Advantage Platinum and EPS |
Initially, we plan to enjoy the space for entertaining and as an expansion of our house, as well as guest quarters. We’ll likely use it as a short-term rental periodically, too. It’s also a great example of the kind of building our construction clients can expect, so we’ll utilize it as a ‘show home’ as well.
We’d initially built the space keeping in mind the possibility of our mother moving in, in a few years. Since that looks less likely now, we’ll probably stick to the entertaining/short term rental.
We went to an ADU symposium and the ADU tour. On the tour, we asked homeowners and builders a lot of questions about what they would do differently if they were to start over. Since we were going to do the majority of the work ourselves and I am a General Contractor, I had a pretty good idea of how to budget for this job.
We had to get a variance for height restrictions and the slope of the roof. We had to sink the garage 2′ and bring up the landscape so that it would meet the restrictions. The variance was an extra $2,000 and 12 week process. Working with BDS was fine but the restrictions at that time were ridiculous!
We’ve built quite a bit of flexibility into this multifunction ADU, and our ROI will be recognized over the years through short-term renting and via the equity we’ve built by doing the majority of the work ourselves. We also hope to gain some level of return by using this as a show home for the construction business.
This ADU is Earth Advantage Platinum certified. The ceiling has 3″ of foam insulation with additional bat insulation, bringing it to R39. The walls have a blanket of blown-in fiberglass at R33. The lighting, insulation, exhaust system, windows, exterior are energy efficient, and the exterior plywood was crafted without formaldehydes. Low-voc paint was applied.
We love the interior architecture and open concept. Since we have several trees around us, we wanted to feel like we were in a tree house. The skylights, vaulted cedar ceiling with the exposed post and beams and large wall of windows accomplished our vision. The colors and feel of the ADU are designed to match the house itself.
It’s really gratifying to look at the finished product and realize that we completed it ourselves–the design choices and construction were a labor of love and we are proud of how it turned out.
We would have love to have interior stairs, but the space was better utilized by having them on the outside; we plan to integrate them into a landscape in the future. We were also not thrilled with the requirement to drop the ADU 2′ lower than ground level in order to meet strict height requirements at the time.
If we were to start over, we might nix the idea of a garage and turn the entire thing into a 2-story ADU. Next time!
We were surprised by the extensive permitting regulations in building an ADU in comparison to new home or remodeling construction.
Know your own limitations–what is your time worth vs. hiring out certain pieces of the process, how quickly can you get something done (well) vs outsourcing it? As owner-builders, we took a lot longer than we thought we would because of competing interests, our day jobs, and the difficulty we had making the design choices that are routine with any new construction.
We’ve always been interested in smaller-footprint living spaces and are big fans of urban density that takes the form of smaller structures housing more people in the same area. One half of our old backyard felt like a wasteland, so it made perfect sense to add another unit of housing. We already had a nice outdoor space in the existing patio, and we were used to hanging out in it and chatting with neighbors over the fence, so it felt natural enough to just add another neighbor!
Since we love our neighborhood and its proximity to everything we need, our long-term goal is to stay in our home as long as possible – when the “big” house gets too cumbersome to care for, we’ll rent it out and move out back into the ultra-manageable 250-sq ft ADU.
Type of ADU | Detached, new construction |
Architect/Designer | Willie Dean, Ground Up Design Works, http://www.groundupdesignworks.com |
General Contractor | Joel Shimmin, Manx Design Build, joelshimmin@gmail.com |
Heating System | Ductless minisplit |
When did you start the design work? | 4/2015 |
When did you submit the plans to the City? | 12/2015 |
When did you start construction | 5/2016 |
When did you get your certificate of occupancy? | 12/2016 |
Total Square Footage | 250 |
Total Cost (including sweat equity) | $120K |
Cost/Square Foot | $480 |
Sweat Equity estimate (part of the “Total Cost” listed above) | None |
Other special project costs |
custom Murphy bed ($3.4K) built-in couch -worth every penny because of the space savings and craftsmanship ($2K) |
Long-term rental
We’ll continue to use it as a long-term rental until we’re ready to downsize from the main house and move into the ADU…but that’s waayyyy off in the future :-).
I (Anne Marie) attended Kol Peterson’s one-day ADU course, which was a huge help for downloading all pertinent info into just a few hours. At Kol’s class, we toured an ADU that was under construction, designed by the architect we ended up selecting for our project, Willie Dean. Willie came by and visited our site and determined it was a feasible project, so we took out a HELOC with Advantis CU to finance it. Willie recommended a couple of contractors, and after meeting with them, we selected Joel Shimmin as the GC. Our initial target budget of $80K was far too unrealistic given our inability (due to time & lack of skills) to contribute work to the project, but both Joel and Willie managed our expectations well on the project-cost front.
Our architect handled all the interactions with BDS. Other than having to change our design to make one side of the ADU a firewall (the side facing our main house), we didn’t have any big hiccups – other than a lot of extra work for the architect.
We’ll have paid off what we owe in the next 8-10 years, but we’re really looking at it for the long haul – it’s our future home.
Cork flooring, Paperstone countertops (250-sq-ft footprint is the greenest feature, though)
We’re quite pleased with how large the space feels for being so small. Our architect designed it so it’s very light and airy with all the windows, especially the ones up high at the roof split, and the bump out for the built-in couch makes it feel much wider than it actually is.
We’re most proud of the size and livability of the space and are thrilled about providing a home for a tenant wanting to live in a house-like setting in a vibrant, close-in community.
We’re not *unhappy* with them, but we would have preferred a more streamlined look to the open shelving in the kitchen, something that was shown on the architectural drawings but that we didn’t engineer into the building process.
We would start out with a more reasonable budget so we wouldn’t have to pay the extra fees to increase our HELOC ;-). (Note: Our architect, contractor, and credit union told us up front it would end up costing what it did – listen to those who know!)
How low stress it was for us – but that would be because our contractor Joel took on all the hard stuff.
Unless you’re prepared to do a lot of the work yourself and have plenty of free time, don’t go into it trying to build it on the cheap. After all, you’re spending tens of thousands of dollars on an investment, so it’s worth doing it right and having a product in the end that you’re proud of and can trust is done right and well.
Hire an architect who can handle small spaces – our unit feels much larger than its 250 sq ft because of the design elements the architect brought to the table.
Most importantly, hire a contractor you like and trust and will enjoy working with. Ours was up front and transparent throughout the whole process, and he brought some great ideas to the table that ended up making the project so much better.
Oh, and if you’re not the patient type…learn to be. It takes time, but don’t all good things?
~Return to Top of page~
We wanted to work on a real estate project and building an ADU is a unique way to create housing in the Portland market.
Type of ADU | Attached bump out |
Architect/Designer | Carly Boynton, Grain Designhttp://www.graindesignbuild.com/ |
General Contractor | Mark Akita |
Heating System | ductless mini split |
When did you start the design work? | 8/2015 |
When did you submit the plans to the City? | 10/2015 |
When did you start construction | 11/2016 |
When did you get your certificate of occupancy? | 7/2017 |
Total Square Footage | 500 |
Total Cost (including sweat equity) | $106K |
Cost/Square Foot | $212 |
Sweat Equity estimate (part of the “Total Cost” listed above) | I was heavily involved in all aspects of the ADU project, from the beginning of the design phase, through to the completion of the building stage. Its hard to put a number on all the hours, weeks, months, years of labor spent doing the varied things needed to pre-plan, plan, and complete this project. From personally getting the plans passed through the city (which did not come without challenges) to manually renovating our landscape to selecting and collaborating with vendors for various parts of the construction phase, we treated this project as a second job for both us. |
Other special project costs |
We had a large stamped concrete patio that we needed to remove and the roof line of the ADU impacted a balcony and large window in a second floor bedroom of our home. So we need to remove the patio and modify the door and window upstairs. ($4K). |
Initially we will likely host guests and in the future potentially rent out to longer term residents or have family members live there.
In the future, we may continue short term rentals but will also have the option to house family members for longer periods of time.
Several years ago, in our first home, I managed a project to convert the back section of the house into a stand-alone ADU. I took Kol’s class to brush up on the process and learn of any new information. I originally intended to implement the plan myself and began contacting various subcontractors and prepared a budget. Ultimately, we decided to work with a contractor to manage the process.
We have large trees on our property, so we needed to hire an arborist to write a formal tree plan. Additionally, many trips were required to the development office whereas I spent a lot less time at the development office when I had my 2011 ADU built.
Total cost to build was approximately $106,000. There were additional costs to furnish and prepare for a short term rental. My goal is to have this completely paid of in five years. It will be great to have this additional living space on the property which can be used in so many different ways in the future, such as housing for friends and family or simply continuing to use as a rental (long or short term).
No additional features were used.
The landscaped pathway really creates a wonderful journey around and up to this wide open space with high ceilings and many openings for light to pour through. Our design/builder, Carly Boynton, did a great job of orienting the building to create an open and peaceful space.
We took a space on the property that was simply not being used for any purpose and are now sharing this space with travelers and guests to vacation and relax.
The electrical switches in the bathroom are not intuitive. I wish I had noticed they were not all combined into one switch before the project was over.
Undertaking large construction projects can be very stressful. Having both managed one and handed one over to a general contractor, there are pros and cons to both. Hindsight is 20/20 so without that vantage point during the process, I would say it’s important to remain positive, and to continually ask yourself what is something positive that you can contribute to the project.
Being that I had managed an ADU process in the past, I didn’t come across anything that was surprising. I am familiar with the design process, the development offices at the City of Portland as well as the construction process.
I would recommend seeking out an excellent creative team. Jeanne Mare Werle of Lunar Blue Color & Design (https://www.jeannemarewerle.com/) was integral to creating this space regarding fixtures, finishes and colors. In addition, we were grateful to connect with Beneath the Bark (https://www.beneaththebarkfurniture.com/schedule-appointment/) who created our barn doors as well as custom made furniture. It’s also very important to work with a design/builder such as Grain Design who is going to understand the needs for your specific property. For us, having a design/builder is the foundation (pun intended!) needed to have a successful ADU built.
We were looking for flexibility in terms of income and space for hosting family.
Type of ADU | Detached, new construction |
Architect/Designer | Mitch Snyder, msnyderarch.com |
General Contractor | Jamie Rivers |
Heating System | ductless mini-split |
When did you start the design work? | 9/2015 |
When did you submit the plans to the City? | 7, 2016 |
When did you start construction | 10/2016 |
When did you get your certificate of occupancy? | 1/2017 |
Total Square Footage | 640 |
Total cost (including sweat equity) | $145K |
Cost/Square Foot | 226 |
Sweat Equity estimate (part of the “Total Cost” listed above) | $15K |
Other special project costs |
none |
Mix of short-term rental and guest house for family visiting from out of town
We would ultimately like this to be a longer-term rental to contribute to affordable housing in Portland at some point in the future.
We didn’t do anything, but wish that we had! It was quite a learning experience for us.
We received different information from the various inspectors, which was frustrating. It was hard to get in touch with an actual person without going down to BDS, and then the fact that they sometimes closed at 3pm made it hard for someone who works regular hours to get there. However, most of the folks that we worked with were helpful.
We were able to pay for a good portion of the ADU with our savings, so we expect to pay off the debt we incurred within 5 years.
R33 insulation; high efficiency windows
On the interior, we love the shed roof and all of the windows, both of which make the space feel large. On the exterior, we like the cedar soffits that accent the dark exterior paint. The ADU has a cabin-like feel to it, which is accented by the two hemlocks out front.
Generally, we are happy with the use of space and materials. And that our new marriage survived the process.
We don’t love the Hardie board, but had to use that to minimize cost. We also wouldn’t use a wooden window in a shower again.
We would have made it slightly larger. We had the space to increase the size but were trying to minimize cost. We also would have submitted for the short-term rental permit a LOT earlier. The process for getting the rental permit took much longer than the city projected on their website.
We were surprised by a few big costs (i.e. digging the sewer) that kept inflating the budget. We were also surprised by how much of our time it took. There were a *lot* of decisions that had to be made at the last minute and required immediate attention – lighting plans and fixtures, faucets, finishes, etc. We also got surprised by the rain. The ADU was framed during the late fall of Portland’s wettest winter on record, so the project was on hold for several weeks while we ran heaters and de-humidifiers to dry out the lumber.
We worked with a small architect and small contractor, who allowed us to manage costs, do a lot of work ourselves, and have a lot of control in the design. The tradeoff is that the project probably took longer than it would have with a larger firm and required more of our personal time. Also,
I also suggest that you set up a budget and schedule in a Google Doc and then revisit it with your contractor and architect regularly. We did this about half way through construction, and it really helped organize all of the many emails that were flying through inboxes.
My daughter and family bought a home with a large back yard. They introduced the idea of an ADU for me to reside in. Being close to children and grandchildren was a draw in addition to living near to family as I age which brings the possibility of my needing more assistance.
Type of ADU | Detached new construction |
Architect/Designer | Lily Heller, lilyheller@gmail.com |
General Contractor | Rachel Cook, dogwoodconstructionpdx.com |
Heating System | ductless minisplit |
When did you start the design work | 6/2015 |
When did you submit the plans to the City? | 3/2016 |
When did you start construction | 7/2016 |
When did you get your certificate of occupancy? | 11/2016 |
Total Square Footage | 560 |
Total Cost (including sweat equity) | $139K |
Cost/Square Foot | $248 |
Sweat Equity estimate (part of the “Total Cost” listed above) | $2500 + whatever monies I put in for landscaping |
Other special project costs | $1200 for tree fund as a plum tree in poor condition was removed. The $2000 needed to locate, excavate and fill 2 cesspools that had already been decommissioned. |
I am living in the ADU as it is in the backyard of my daughter and family. We are discussing the possibility of occasionally using it for short term rental.
Possibly short term rental through Air B&B.
Attended Kol’s ADU seminar and tour. Researching online and talking with others who had or were considering building an ADU. We did discuss converting the garage to part of an ADU but ultimately decided to have a separate ADU.
Locating and evaluating the condition of 2 cesspools. The city has no documentation of cesspools – whether they have been decommissioned or are still in use.
The total cost of the ADU was approximately $139,000. I will live in the ADU until no longer independent. Assuming that this may be 10 years and that I could likely pay up to $1500/month to rent even a smaller space, the total for 10 years of rent could be $180,000. Ostensibly, my savings for this 10 years could then be $41,000.
Rinnai On Demand Gas Water heater. High Efficienty Interior Lighting Systems
I am truly happy with the whole project. I love having a master bedroom in addition to a den/second bedroom. The ADU feels much larger than the 560 sq feet it is.
I love the open feeling with all of the windows and skylight. The bathroom has fulfilled a dream with the tile floors and bathtub surround. I am very proud of the kitchen.
Right now, there is nothing with the ADU itself that I am not content with. I do wish that I had saved some of the excavated soil to use for fill in areas needed for proper landscaping.
I would be more involved in obtaining the permit so that I would know exactly what the requirements are. I would also consider what landscaping might be required when project complete – e.g. need for more fill dirt in certain places which might be taking care of with excavation at the beginning.
That there are endless things to learn – tree removal information, locating cesspool(s), etc, etc. Also learned that, despite best cost estimates, there will always be unexpected charges so consider adding a few thousand dollars to your budget at the beginning.
If there are trees that need to be removed that appear to be in poor condition, I would have an arborist complete a report that the city can provide indicating the condition to avoid need to contribute $1200 to the tree fund. Make an effort to determine if there are cesspool(s) in area where ADU will be built so that cost of decommissioning/filling can be determined prior to project start.
A strong rental market along with online rental platforms like Airbnb, the investment return seemed like a good idea. Also, having a corner lot created the privacy we were looking for despite having a tenant in the backyard. The SDC fees the City was waiving to encourage infill development was also something I was looking at closely as a means to reduce overall costs.
Type of ADU | ADU above a garage |
Architect/Designer | Matthew McCune, http://www.mccunedesign.com |
General Contractor | Michael Gentry, http://www.mgentryconstruction.com |
Heating System | Ductless mini-split |
When did you start the design work? | 12/2015 |
When did you submit the plans to the City? | 3/2016 |
When did you start construction | 7/2016 |
When did you get your certificate of occupancy? | 2/2017 |
Total Square Footage | 466 sq ft above a 466 sq ft garage. |
Total Cost (including sweat equity) | $160K including the garage |
Cost/Square Foot | $171 (including garage) |
Sweat Equity estimate (part of the “Total Cost” listed above) | None |
Other special project costs | Ended up installing a separate electric service/meter for the ADU as I didn’t have capacity in the main house ($2K). |
Primarily the ADU will be used as a short term rental.
We plan on using the ADU as a short term rental for the foreseeable future which will allow us to keep it open for friends and family when they visit.
I attended several ADU tours over the last couple of years to get sense of project costs and construction ideas. AccessoryDwellings.org was also extremely helpful understanding the entire process and what unforeseen issues could come up.
Working with BDS was fairly straightforward. We originally submitted an application for a land use review and we were quickly told it wasn’t required.
With a 160K investment and based on current rental income, the payback should fall within 10-years. This will provide a second stream of income that will help pay the high MultCo property taxes!
None (tight budget).
We are really happy with how the space is utilized. At being under 500 sq/ft, the space feels warm and inviting. We are also happy with the fact we decided to keep the garage space rather than converting the entire building to an ADU.
We spent extra time and money on the exterior of the building to ensure it blended in with the existing house and neighborhood. We also really love the large window that opens up to the balcony, which make the entire until feel much more open.
I wish I would have considered an overhang of some sort to protect the balcony from rain (did you know it rains in Portland?).
In hindsight, I would have tried to incorporate a way to protect the front balcony from rain, which is something that didn’t cross my mind during the design process.
Decisions, decision, decisions. There were so many decisions that had to be made quickly to keep the progress moving forward, especially when sub contractors are on a tight schedule.
Be flexible and be prepared to make a lot of decisions quickly. The more you can be prepared the easier the process will be. Also, ensure you have an open line of communication with your contractor to fully understand how decisions impact budget.
We were looking for a way to live in our house for the rest of our lives and to generate at least some income in the process. An ADU offers the possibility of care-giver lodging in the future or even a place for us to live while we rent out the main house if we get to the point where we can’t handle the stairs any longer.
Type of ADU | Basement conversion ADU |
Architect/Designer | Dave Spitzer, Architect, http://www.dmsarchitects.com/ |
General Contractor | Weitzer Company http://www.weitzercompany.com/ |
Heating System | Cadet baseboard heaters in all rooms plus an electric fireplace |
When did you start the design work? | 4/2015 |
When did you submit the plans to the City? | 12/2015 |
When did you start construction | 6/2016 |
When did you get your certificate of occupancy? | 12/2016 |
Total Square Footage | 795 |
Total Cost (including sweat equity) | $261K |
Cost/Square Foot | 328 |
Sweat Equity estimate (part of the “Total Cost” listed above) | We did all of the interior painting, which was likely worth about $5K of our time, but we also put lots of time in making product selections, coordinating deliveries (we did a lot of our own purchasing), and otherwise making sure that everything was available to the contractors on time. |
Other special project costs | There were lots of things that added to the cost. Our large egress windows were custom fabricated to match the historic windows upstairs as required for Historic Resource Review. That cost roughly $2500 more than otherwise. We had to remove two pillars in the basement to clear space for the bedroom and living area and reinforce the floor above with steel beams — costing roughly $6000. We also had to shave two feet off the corner of our very large chimney base to provide for adequate hallway clearance to the bedroom — costing about $3000. Then we stipulated full STCC 55 sound insulation barriers between the ADU and our first floor, which cost an extra $4500. |
We are currently operating it as a short term rental through AirBnB
After a few years we may switch to a long-term rental, and ultimately we expect to have a caregiver living there so we can stay in our home longer.
Attended the Kol Peterson class, attended an AirBnB hosting class. Interviewed three architects before selecting Dave Spitzer.
Submitted Irvington Historic Resource Review docs in August, 2015, approved October, 2015, permits filed with City, December 2015
Our experience with BDS was generally positive. The only issue that came up was the address splitting. BDS assigned us an ‘A’ and ‘B’ address for our main house and our ADU. But our ADU has a separate entrance facing a separate street, and for convenience and to avoid confusion, we wanted a completely separate address on the other street. We finally had to go to the Permit Center and talk to the address assignment staff who worked it out with their building code folks that we complied with the “duplex” code and therefore could have a completely separate address. The “duplex” requirement included sound insulation of at least STCC 45 between the unit and the first floor of the house, and we had designed in STCC 55, so we met the test.
One of the reasons we are going with an AirBnB short-term rental is the increment of revenue for the immediate term versus a standard long-term rental. We are expecting short-term rental revenue to be about 40% greater than market rate long-term rental revenue — partly because we are in a good location for short-term visitors. We expect about a 10-year payback, which isn’t great, but we expect the value of the property to be enhanced over the long term by this expanded revenue producing ADU.
All walls are insulated, windows are double pane and some have additional Indow Window inserts.
Our architect recommended a huge egress window in the kitchen/dining area which wasn’t required by code, but which brings lots of light and helps avoid the “in the basement” feel. We have been very pleased with the “luxury vinyl planking” flooring, which has a warm feel and is nearly indestructible. We’re also delighted with the openness made possible by removing the pillars in the living room. We were blessed with high ceilings in our basement, and that also helps make it feel like a normal part of the house, not a converted basement.
We are pleased that we have been able to provide more housing density on our property and still be in keeping with the historic character of our home and meet the requirements of Historic Resource Review in the Historic District. We have been pleasantly surprised by the many positive comments from our AirBnB guests who love the space.
Dealing with the loss of basement storage space has been a challenge, but we have purged a lot of stuff and are more-or-less adapted to it now. Other than that, were really happy with the result.
We likely would not do any of the work ourselves were we to start over. We had to scramble to keep up with the contractors as we did the interior painting, and couldn’t do it as quickly as professionals would have. We likely should have gone back over the costs more diligently earlier, as we wound up going way over our original budget.
In this economic climate the owner has very little leverage over contractors and subs to work on keeping costs down. We had not experienced that in major remodeling project we had done in prior years. We were surprised and pleased at the talent of our contractor’s on-site management in handling the dozens of trades with close scheduling and coordination.
Go over the costs very carefully and give lots of thought to how you’ll function with a much smaller basement area than you have now. Recognize that plumbing and ductwork that may hang down from your basement joists may have to be relocated at potentially considerable cost. Think carefully about where your egress windows will be located and what the security implications of that will be. If you do plan on using the unit for a short term rental, investigate thoroughly the special requirements imposed by the City for obtaining that permit and make sure that your architect and contractor build in the required features. Think about how you live in your home, and how having downstairs neighbors will change what you can and can’t do with your space and what investment you are prepared to make in sound insulation.
Part of our retirement plan.
Type of ADU |
Basement conversion and addition |
Architect/Designer |
Beate loanide-Culi, rnbdesign.org |
General Contractor |
Alex Loanide, westernoregonbuilders.com |
Heating System |
Cadets and a Panasonic vent/heater in bathroom |
When did you start the design work? |
1/2016 |
When did you submit the plans to the City? |
2/2016 |
When did you start construction |
5/2016 |
When did you get your certificate of occupancy? |
4/2017 |
Total Square Footage |
659 |
Total Cost (including sweat equity) |
$150K |
Cost/Square Foot |
$227 |
Sweat Equity estimate (part of the “Total Cost” listed above) |
$40K |
Other special project costs | We added a new sewer line instead of using a pump system for new unit ($6K) |
We are using for friends & family for first couple months after completion. We are working with CHBO because we would like to try long term rentals of 30 plus days.
Family & friends, long term rental and eventually we will move into it. We would like to move into it now but our beautiful cat Shanti would hate it.
I have been a contractor for sometime so I was informed. We talked to several contractors and some would not even come to look at project because we refused to lift the house. No financing was done.
They required an off street parking space to be available and increase water meter size.
The sooner the better, hard to know how long it will take. No financing was done so it’s a little less pressure.
None
We were most happy with Beate because she was willing to have us very involved and allowed us to change some of the design ideas. What I am most happy about is meeting and working with Beate. We love everything about the unit.
Adding the driveway addition (living room) with all the windows took away the basement feel of the under house area. I love the bean expose and the step down.
No bathtub.
Happy with it all.
The city isn’t consistent with requirements from one job to another.
I would advise them to use Beate & Alex for the project.
Investment and income
Type of ADU |
Detached new construction |
Architect/Designer |
Design Build Portland, http://www.designbuildportland.com/ |
General Contractor |
Design Build Portland, http://www.designbuildportland.com/ |
Heating System |
ductless minisplit |
When did you start the design work? |
11/2014 |
When did you submit the plans to the City? |
2/2015 |
When did you start construction |
6/2015 |
When did you get your certificate of occupancy? |
3/2016 |
Total Square Footage |
650 sq ft ADU plus 600 basement |
Total Cost (including sweat equity) | $225K |
Cost/Square Foot |
$180 (including basement) |
Sweat Equity estimate (part of the “Total Cost” listed above) |
$30K |
Other special project costs | New water service ($5k)
garage demo ($3k) |
Certification & Energy Scores | Earth Advantage Platinum and EPS |
Family, short term rentals
Same as above, or rent it out long term and live abroad
Personal research, spoke to a few builders, researched financing options.
It just took a long time for permits to be issued
It will pay for itself in 5-6 years, we did not finance it so we get every penny in income and pay no interest. Added value to existing property and the potential for being able to retire to a less expensive country. Lots of flexibility in many ways.
Earth Advantage
The integration of light, reclaimed materials with the new, and how the design mirrors the original house.
Art studio, reclaimed materials, landscaping
Less light in art studio
Nothing except have more money to spend on it.
How costs add up quickly, especially with all the potential upgrades
Hire a designer to work with if you are not experienced in that area. Have it all planned out before hand because the decisions to be made come fast towards the end and you should be prepared if you want the project to be completed in a timely fashion.
You must be logged in to post a comment.