Special inspections are third-party inspections that apply to certain types of construction work, often installation processes that determine final performance but may be invisible once completed. They are separate from the standard building inspections performed by the city or county during the permitting process.
These inspections can apply to residential, commercial, and other types of construction projects. Homeowners often first learn about special inspections during permitting or construction, especially if they have never completed a major remodel, addition, or new home before.
Why are special inspections required?
Special inspections help verify that contractors install certain parts of construction correctly and in accordance with the approved structural drawings and engineering. Projects typically require these inspections for work that is especially critical to the safety and performance of the building.
What types of construction work commonly require special inspections?
Special inspections most commonly apply to structural work and engineered building systems. Depending on the project, special inspections may apply to things such as:
- Structural steel
- Welding
- Reinforced concrete
- Epoxy anchors
- Retaining walls
- Soils compaction
- Deep foundations or helical piers
- Certain engineered wood or seismic connections
- Hillside construction or other unusual site conditions
Who performs special inspections?
Special inspections are performed by qualified third-party inspectors or testing agencies with expertise in the specific type of work being inspected. Depending on the project, this may include inspectors specializing in soils, concrete, welding, or structural steel.
These inspectors work separately from the city or county building inspector and typically provide written reports documenting that the work complies with the approved drawings and engineering.
Wait — isn’t the city already inspecting my project?
Yes — your project will still receive standard building inspections from the city or county as part of the normal permitting process. Those inspections occur at major milestones during construction, such as foundation, framing, and final inspection.
Special inspections are different. They focus on specific types of structural or engineered work that require additional expertise or observation during installation. In many cases, the special inspector observes a particular portion of the work while the contractor performs it, rather than reviewing the project more generally at scheduled permit inspections.
When during construction do special inspections happen?
Special inspections typically occur while specific work is actively being performed and before that work is covered up by later construction. Depending on the project, this may happen during excavation, foundation work, concrete placement, structural framing, welding, or installation of certain engineered connections.
What happens if a required special inspection is missed?
Missing a required special inspection can delay construction, especially if the contractor has already covered up or completed the work before the inspector has a chance to observe it. Depending on the situation, the jurisdiction or structural engineer may require additional investigation, testing, or even removal of finished work so the installation can be verified.
Because of this, the contractor needs to coordinate required special inspections carefully during construction.
How would I know if my project requires special inspections?
During design, the structural engineer identifies any required special inspections and notes them on the permit drawings. If a project requires special inspections, the approved construction documents include a structural note or special inspection schedule that outlines those requirements.
Who coordinates special inspections during construction?
The contractor is responsible for coordinating special inspections during construction. Because many special inspections must occur at specific points in the work and before later construction covers up the installations, the contractor schedules inspections as the project progresses.
Do special inspections add cost to a project?
Yes. Special inspections add costs beyond standard permit fees and city inspections. The type and number of required inspections, the complexity of the project, and the number of site visits during construction will all affect the cost.
Who hires and pays for the special inspector?
The property owner hires and pays for the special inspector or testing agency. This keeps the inspection independent: the special inspector is working for the owner, not the contractor performing the work.
The contractor may help recommend a special inspector or testing agency, but the owner pays those costs as part of the overall construction process.
How can I avoid surprises with special inspections?
The best way to avoid surprises with special inspections is to address them early during the design process. A well-coordinated set of construction documents helps identify required inspections before construction begins, allowing the contractor to plan and schedule the work appropriately.
At Christie Architecture, we coordinate closely with our consultants, including the structural engineer, throughout design and construction documentation. During construction, we remain involved in the project through construction administration to help answer questions and support the overall coordination of the work.
For projects within the City of Portland, additional information about the administration of special inspections is available through the city’s permitting resources.