Before drawing a full set of plans for an accessory dwelling unit, it helps to know whether the idea fits the property and the budget. A feasibility study is an early, focused look at those questions. It is not a permit set or a construction bid. Its value is in identifying the main opportunities and constraints before you commit to a larger design process.
What the study checks
Fold Architecture begins every project with a paid two-hour feasibility study. The study considers what the lot and budget can really do, including zoning, setbacks, and a rough construction cost. For an ADU, those questions shape the basic options: where a building might fit, how large it might be, and what challenges could affect the project.
Zoning and setbacks are not abstract details. They help define the area in which a building may be placed and the limits that shape its form. The lot’s existing buildings and conditions matter too. A useful early conversation considers access, likely utility needs, privacy, and the relationship between the ADU and the main home. These factors can influence both design and cost.
The construction cost is rough by design. At this stage, it is a planning tool, not a guaranteed price. It can help reveal whether the current scope appears aligned with the budget, or whether the project needs a different size, layout, or approach. A realistic early estimate is more helpful than a precise-looking number unsupported by developed plans.
How to prepare for the conversation
Bring what you already know about the property and your goals. Useful information includes the street address, a survey or site plan if you have one, photos, and any relevant records about existing structures. Also think through how the ADU will be used, who will live there, and what matters most: a separate entrance, a particular number of rooms, accessibility, outdoor space, or a target budget.
You do not need to have solved the design in advance. It is more useful to describe the need than to arrive attached to one exact footprint. If there are known issues, such as a steep site, an existing building you want to keep, or a tight access route, raise them early.
What happens after the study
The study helps establish whether the project appears workable and what questions should be answered next. Some sites may call for additional investigation before a design can be confirmed. Requirements and conditions are property-specific, so an early review should not be mistaken for formal approval from the city or a contractor’s final quote.
Use the findings to decide whether the project’s likely scope matches your priorities and finances. If you’re considering an ADU or another residential project in Portland, get in touch to request a feasibility study.