Sandy sits on US-26 between Gresham and the Mt. Hood corridor. It’s the last incorporated city before the highway climbs into the canyon. Pioneer Boulevard is the main street, and the mountain drives the weather. City of Sandy and unincorporated Clackamas County are different reviewers, so a downtown address and a five-acre parcel toward Estacada can share a mailing city and still file in different systems.
Wolf builds in Battle Ground, Washington. Delivery runs I-5 and I-205, then east on US-26. We don’t have a recorded Wolf delivery in Sandy yet, but the city is inside our Washington-and-Oregon turn-key area, and we review lots here the same way we do in Gresham and the rest of east Clackamas County.
City of Sandy or Clackamas County first
Look up the parcel on Clackamas CMAP before you sketch anything. If the lot is inside city limits, Sandy Development Services and the Sandy Development Code apply. If it isn’t, you’re in county land use, even when the mail says Sandy. Lots toward Brightwood, Welches, and Government Camp are usually county mountain files.
Oregon cities over 2,500 must allow at least one ADU on qualifying single-family lots inside a UGB (ORS 197A.425), and HB 2001 blocked owner-occupancy and extra off-street parking mandates for long-term units. Local rules still matter. For county requirements, read our Clackamas County ADU guide. See the Oregon ADU rules guide for the statewide ADU rules.
Inside Sandy, accessory dwelling units are a listed accessory use in several districts (SFR, R-1, R-2, R-3, C-1, and C-3 in published tables), with standards in Chapter 17.74, including § 17.74.70. Size caps change, so we read the current section the week you file. Published 17.74.70 tables have listed a 720-square-foot maximum, a three-occupant note, setbacks that follow the zone, and no off-street parking minimum for the ADU. A 2022 land-use order applied the 720 figure. A later prefab-housing packet discussed raising the maximum, with 900 square feet or a percentage of the primary dwelling mentioned. Until staff confirm the current section, we treat 17.74.70 as the controlling document and verify the number.
Other points that have appeared in the published 17.74.70 standards:
- The ADU shall be accessory to the primary residence.
- A pedestrian walkway, of specified materials, connecting the ADU’s primary entrance to the public sidewalk.
- An ADU may be stick-built, modular/prefabricated, or a manufactured home in compliance with the design section. That’s why a factory-built home is an option here.
- Detached ADUs have been asked to include a set number of design elements on street-facing façades, plus a minimum ground-floor window percentage.
- An ADU has been listed as not permitted on the same lot as a duplex.
Anything not covered in the current 17.74 depends on the lot. Ask with the address.
Unincorporated Clackamas County lots with a Sandy mailing address go through county planning and building (ZDO 839). Rural and mountain lots toward Mt. Hood follow different and usually tighter rules, and most of them aren’t inside a UGB.
How Sandy takes a permit
Sandy staff review what you submit. Incomplete design sheets, a missing walkway, and a last mile that only works in August are common reasons a file comes back. Here’s the order we work in:
- Confirm the zone allows an ADU, using CMAP and the current 17.74, and confirm it isn’t a duplex lot if that prohibition is still in the code.
- Plot plan: existing house, proposed cottage, the zone’s setbacks, the walkway to the sidewalk, utilities, and a truck path that works on Pioneer Boulevard or a Bornstedt driveway, including in winter.
- Engineered modular plan set. Wolf homes are modular, built in Battle Ground under Oregon’s BCD prefabricated-structures program, delivered with a state insignia of compliance, and placed on a local foundation. They aren’t HUD (the federal standard for manufactured homes) manufactured homes and they aren’t on wheels. Sandy still reviews the foundation, placement, utilities, and 17.74 design items.
- Submit to the city (or Clackamas County if unincorporated), including how water and wastewater will be handled. Site prep is part of the job.
- Inspections as called, then occupancy. Keep the approved drawings on site.
A typical city submittal includes the application, a site plan with property lines and setbacks, floor plans, elevations showing the design elements, the walkway, and utility letters. Oregon BCD inspects the module in the factory, and Sandy inspects the foundation, placement, and utility connections.
County lots use the county’s urban or rural ADU path instead of 17.74, whatever the mailing address says.
Lots we see
Downtown Sandy is a highway town with a real main street, older houses, and weekend ski traffic on US-26. The older blocks off Pioneer Boulevard can be tight, with short lots and on-street parking. Bornstedt and the bluff-area plats are often wider but still have HOA (homeowners association), tree, and drainage questions, and they’re still subject to whatever size limit the current 17.74 sets. Toward Estacada the lots look rural. Toward Welches they pick up snow, grade, and a US-26 last mile that can close in storms. Lots toward the mountain can look like they’re in the city and still file as county, so check CMAP first.
Sandy River-adjacent and low parcels raise floodplain and geotech questions. If the lot is in a flood overlay, mention it on the evaluation.
Delivery on US-26
Delivery from Battle Ground is a metro run followed by a highway climb, and winter on US-26 is part of the plan. We won’t promise a January set on a steep driveway just because the home is ready at the factory. A 12-foot-wide Model K is easier to get in than a 14-foot E on a street with parking on both sides, and overhead lines, firs, and driveways built for a passenger car still decide the day. Pioneer Boulevard, Bornstedt, and the bluff roads are each different last miles. Ski-weekend traffic, school pickup, chain-up requirements, and storm closures all go on the schedule.
Models
Wolf doesn’t sell HUD-code manufactured homes, and a home on wheels doesn’t count as an ADU here.
- Model K (~432 sq ft). One-bedroom guest or rental ADU on a typical city lot.
- Model E / Model F (~616 sq ft). Two bedrooms when the current 17.74 size limit and the zone both allow it.
Model J (~828 sq ft) is over the published 720 limit, so it would need confirmation under the current code, not a 2024 discussion draft, before it could be the plan. We match the model to the section staff will actually apply.
County rural and mountain lots use the county’s size table instead of Sandy’s. That usually covers parcels in the canyon and the ski corridor toward Mt. Hood.
ADU, tiny home, or granny flat
If it has a kitchen and bath, Sandy treats it as a dwelling. “Tiny home,” “granny flat,” and “ADU” all go through the same 17.74 file and carry the same factory insignia. Family use and long-term rental are the usual choices. Short-term rentals fall under separate local rules, and owners near the mountain sometimes want a vacation unit, so don’t assume an ADU permit covers one. Tell us the intended use on the evaluation.
Cost and timeline
The model gives us a reliable starting home price. We price trenching, electrical capacity, winter access, and any required design elements after reviewing the property. Factory construction keeps the home out of canyon rain and snow, but city review and site prep still drive the schedule.
The Model K starts at $85,500 for the home itself. Permitting, delivery, installation, and site work are listed separately in your property-specific proposal. Sandy doesn’t offer the same ADU SDC waiver as Salem, so Oregon SDCs and local connection fees go into the proposal after we confirm current fees for your property.
A Pioneer Boulevard backyard and a bluff acre won’t cost the same, largely because of winter access on the last mile. We quote after a property evaluation. Financing is usually a HELOC, cash-out refinance, or a construction-to-permanent lender who has worked with factory-built ADUs. See financing.
Turn-key service and nearby cities
Sandy is turn-key Oregon for us: permitting support, site work, production, delivery, and setup as one job. Punch-list visits come from the same field crews that set the home, a drive out I-205 and up US-26 when the road is open. None of that changes Chapter 17.74.
Gresham, down the canyon, uses a 900 / 75 percent rule that doesn’t apply here. Mt. Hood, up the canyon, is mostly county. Troutdale and Estacada are nearby with their own permit offices.
Weather, soils, and utilities
Sandy is wetter and colder than inner Portland, and snow on US-26 is a real constraint on the last mile. The house is built indoors. On the lot, silts, winter water, freeze-thaw, and bluff drainage affect excavation and erosion control. Summer is the easier set window. Winter sets happen too, with tighter site controls and a highway that may require chains.
Most in-city lots are on city water and sewer. You still need to check laterals, a cleanout, and whether the electrical service can carry a second dwelling. Outside city limits you’re often on well and septic, where the rural ADU rules and septic design usually decide the project. If you don’t know which you have, it’s the first thing we check.
Site work
Foundation excavation, trenching, grading, and minor tree work are part of a normal Sandy job. A downtown curb that looks like a delivery path, or a bluff driveway built for a passenger car, is why we measure access early, including in snow. We bring a standard delivery trailer, and a crane when the swing needs it. We weather-seal the same day when we can, then finish the mechanical and plumbing tie-ins. Two-piece plans add a day to join the halves.
What to send
An address is enough to start. Useful extras: a survey, a CMAP printout, a prior planning letter, photos of the backyard and the street approach (showing grade and overhead lines), and whether the unit is for family, long-term rental, or a cottage you might live in. We check city versus county, the current 17.74, utilities, and whether a truck can reach the pad in the season you want.
If you’ve already picked a model, we’ll still check it against the current size standard before treating it as the plan. If a lot won’t clear 17.74 or can’t take a truck in your preferred season, you’ll hear that at the evaluation.
After the set
Inspections, walk-through, punch list, keys, and warranty. Sandy inspectors sign off on occupancy for city lots, so keep the approved drawings on site until they do.
Send the address. Tell us city or county, where the building would sit, and whether it’s for family, rental, or you. We’ll match a model to the code that applies.
