Panelised prefab / kit
Walls, floors and roof sections manufactured flat and assembled on site, built to the same residential code as a site-built house. Unlike a modular home it arrives as components rather than finished volumes, so it needs no crane set and tolerates difficult access.
- At 1,500 sq ft
- $150,000–$270,000
- Timeline
- 4–8 months
What this figure rests on
Trade and vendor publications only — indicative
Vendor and trade publication guidance. No official survey separates panelised construction, so treat this as indicative for comparing methods rather than as a budget.
Last verified August 16, 2026 · source
What it costs, broken down
- Panelised prefab / kit — base construction$150,000–$270,000
Published ranges for this method generally cover the structure rather than a complete finished build.
Finishing is not in the package: Kit and panel prices typically cover the structural shell and weather envelope. Interior finishing, mechanical, electrical and plumbing are a normal site build on top, and are usually the larger half of the budget.
Advantages
- Built to the same residential code as site-built, so financing and appraisal are generally conventional
- No crane set and no oversize module transport, which suits narrow or steep rural access
- Shell goes up quickly once the package arrives
Tradeoffs
- Only the shell is prefabricated — interior finishing is a conventional site build with conventional labour costs
- Fewer suppliers than modular, so lead times vary
- Needs a competent local builder for assembly; the package price is not the finished price
What building does to the tax base
Oregon generally limits growth in a property’s maximum assessed value to three percent per year, and treats new construction as an exception to that limit.
In general terms, holding unimproved land tends to mean a low tax base that grows slowly and predictably.
Adding a dwelling generally causes a step change in assessed value rather than a gradual increase, because the new structure is brought onto the roll at its own value rather than inheriting the capped figure.
Illustrative assessed value added: $75,000–$229,500
This range is illustrative only. It applies a wide assumed ratio to construction cost to show rough scale and direction, and is not a tax estimate. Actual assessed value depends on the county’s changed property ratio for the year and the assessor’s valuation, and the resulting tax also depends on the district’s permanent rate.
- Ask the county Assessor how new construction would be brought onto the roll for this property.
- Ask for the current changed property ratio and the applicable district tax rate.