EFU zoning is designed to protect working agricultural land. Building a home or establishing a commercial enterprise on EFU land is strictly regulated by state law (ORS Chapter 215) and county land development ordinances.

Dwellings on EFU Property
Having an EFU zoning designation does not grant an automatic right to build a residence ("building envelope"). Dwellings must qualify under specific statutory categories:

Primary Farm Dwellings: Approved if the tract is actively used for farming and meets state/county farm income thresholds (often requiring tax returns or Schedule F documentation demonstrating commercial agricultural production).
Replacement Dwellings: Allowed if replacing a lawfully established home that still possesses intact exterior walls, roof structure, plumbing, and heating systems.
Non-Farm Dwellings: Subject to conditional use approval. Buyers must prove the site is on low-capability soil, will not interfere with surrounding agricultural practices, and meets county lot-of-record standards.
Temporary Medical Hardship Dwellings: Secondary temporary residences approved to care for an infirm family member, requiring periodic medical re-certification.

Property Tax Special Assessment (EFU Deferral)
Properties actively farmed in an EFU zone qualify for a Special Farm Assessment, reducing property taxes based on farm value rather than market value.

The Tax Rollback Risk: If farmland is disqualified or removed from farm use (e.g., converting land to residential yards or unapproved commercial uses), the county tax assessor can impose up to 5 to 10 years of back-taxes (rollback penalties) plus interest.

Forest zones protect commercial timber production, watersheds, and wildlife habitats. Common designations include Primary Forest (F-1) and Conservation Forest (F-2).

Building a Home in Forest Zones
To build a primary residence on forestland, the parcel must typically qualify under one of three state tests:

Large Tract Test: The owner holds a qualifying minimum contiguous acreage (often 160 acres in eastern Oregon or 80 acres in western Oregon).
Template Test: Evaluates surrounding parcels within a specific study area (a 160-acre square or rectangle centered on the subject parcel). A minimum number of neighboring parcels and pre-existing dwellings must have been legally established prior to 1993.
Lot-of-Record Test: Applies to parcels held under continuous single ownership by the current owner or their family prior to 1985, provided specific soil and forest capability metrics are met.

Wildfire Defensible Space & Covenants
Building in forest zones triggers strict Oregon Department of Forestry (ODF) construction and siting standards:

Defensible Space Standards: Mandatory 30-foot to 100-foot primary fuel breaks surrounding structures (clearing ladder fuels, brush, and lower branches).
Covenants: Property owners are generally required to sign and record a restrictive covenant waiving the right to object to standard forest practices (such as timber harvesting, aerial spraying, or prescribed burning) on surrounding parcels.

When land is unsuitable for commercial farming or timber production, or sits adjacent to established rural residential development, specific planning mechanisms apply:

Goal Exceptions & Rural Residential Conversion
Under Oregon’s Statewide Planning Goals (Goal 3 for Farmland, Goal 4 for Forestland), local counties can take a Goal Exception to rezone resource land to Rural Residential (e.g., RR-2, RR-5) if the land is already physically built upon or irrevocably committed to non-resource use.

Environmental Opportunity & Sensitive Lands (EOP)
Properties containing sensitive environmental overlays—such as big game winter ranges, wetland corridors, or steep slope hazard areas—are subjected to additional site-development reviews:

Overlay Restrictions: Limits home siting, driveway placement, and vegetation removal.
Wildlife Setbacks: Building envelopes must often cluster near existing road access to preserve wildlife migration corridors and forest canopy integrity.
 

Verify Legal Lot Status: Confirm with the county planning department that the parcel is a lawfully created "Lot of Record."

Confirm Dwelling Approval Type: Request historical land-use permits (e.g., Conditional Use Permit, Template Test approval) for any existing structures or unbuilt home sites.

Review Tax Assessment Status: Check whether the land is currently enrolled in a Farm or Forest Tax Deferral, and calculate potential rollback liabilities if changing land use.

Inspect Access & Easements: Ensure legal ingress/egress exists across adjacent timber or agricultural parcels, noting road maintenance agreements.

Verify Water & Septic Approvals: Ensure well rights and DEQ septic feasibility permits align with the intended residential or agricultural use.

Oregon Department of Land Conservation and Development (DLCD) — Statewide planning goals, EFU regulations, and forestland policy.

Oregon Department of Forestry(ODF) — Fire safety standards, timber harvest rules, and forest deferral information.

Clackamas County Department of Transportation & Development (DTD) — Local land-use permits, zoning maps, and planning codes for the Mt. Hood region.