Official Reference Guide

Washington State standards, section by section

This version breaks the Washington standards into the major inspection sections and translates them into plain English: what the inspector is expected to check, and what the inspector is not expected to check.

Open Official Washington WAC

How to use this page

This is a readability guide, not a replacement for the official state text. It is meant to help buyers, sellers, and agents understand the practical shape of the standards before diving into the full wording.

Site

What the inspector should check

Visible grading, drainage, retaining walls, and conditions around the house that could affect moisture movement or structural performance.
Driveways, walkways, patios, and similar site features when they create a visible safety or performance concern.

What the inspector is not expected to check

Boundary surveys, soil engineering, or predicting drainage performance during every possible weather event.
Underground systems or concealed site conditions that cannot be seen during a normal visual inspection.

Structural system

What the inspector should check

Foundations, framing, crawlspace structure, attic framing, floor systems, and other visible structural components.
Signs of settlement, movement, damage, or moisture-related deterioration that are accessible at the time of inspection.

What the inspector is not expected to check

Engineering certification, destructive investigation, or opening walls and finishes to confirm hidden structural issues.
Guaranteeing future performance or ruling out every concealed defect.

Exterior

What the inspector should check

Exterior wall coverings, trim, doors, windows, decks, porches, balconies, railings, eaves, soffits, and related visible exterior elements.
Conditions that suggest damage, rot, water entry, unsafe railings, or deferred maintenance.

What the inspector is not expected to check

Testing every window for perfect seal performance or determining manufacturer warranties and code history.
Inspecting concealed flashing or hidden components that require dismantling to view.

Roof system

What the inspector should check

Roof coverings, flashings, penetrations, gutters, downspouts, chimneys, and other visible roof drainage details.
Evidence of wear, damage, missing materials, and signs that water may be entering or failing to drain correctly.

What the inspector is not expected to check

Walking roofs that are unsafe or inaccessible, or guaranteeing remaining roof life.
Leak testing, dismantling roofing materials, or certifying hidden underlayment conditions.

Plumbing system

What the inspector should check

Visible supply and drain piping, fixtures, water heaters, fuel storage/distribution components where applicable, and normal operating function of accessible plumbing fixtures.
Leaks, improper function, poor drainage, visible corrosion, and other material defects.

What the inspector is not expected to check

Pressure testing concealed piping, inspecting every underground sewer component, or predicting all future leakage.
Verifying water quality or hidden plumbing conditions outside the visible scope.

Electrical system

What the inspector should check

Service entrance components, panels, disconnects, visible wiring, receptacles, switches, and installed fixtures and devices that are part of the accessible inspection scope.
Visible safety concerns such as damaged wiring, double taps where visible, missing covers, improper bonding clues, and other notable defects.

What the inspector is not expected to check

Removing panel dead fronts beyond normal standards-based access if unsafe, or tracing every branch circuit through the house.
Full code-compliance review or latent defect discovery behind finished surfaces.

Heating, cooling, and solid-fuel systems

What the inspector should check

Installed heating equipment, cooling equipment, normal operating controls, visible ducting or distribution components, and fireplaces/solid-fuel features where included in the standards.
Normal operation at the time of inspection and visible defects affecting safety or performance.

What the inspector is not expected to check

Disassembly of HVAC equipment, invasive heat-exchanger testing, or performance testing outside normal operating conditions.
Guaranteeing seasonal performance when weather conditions prevent standard operation.

Interiors

What the inspector should check

Walls, ceilings, floors, steps, railings, counters, cabinets, doors, windows, and the visible condition of the accessible interior living spaces.
Signs of moisture damage, unsafe conditions, notable defects, and normal function of readily accessible interior components.

What the inspector is not expected to check

Moving furniture or stored items, or inspecting cosmetic imperfections as if the inspection were a finish punch list.
Determining every concealed cause of stains or damage without further specialized evaluation.

Insulation and ventilation

What the inspector should check

Visible insulation and ventilation conditions in attics, crawlspaces, and other accessible areas where the standards call for observation.
Conditions that suggest inadequate ventilation, missing insulation, trapped moisture, or other performance concerns.

What the inspector is not expected to check

Calculating full energy performance or confirming hidden insulation in every closed cavity.
Opening finishes to inspect concealed ventilation paths.

General limits that apply across the standards

The Washington standards describe a visual, non-invasive inspection of accessible areas.
Inspectors are not expected to move personal property, dismantle systems, or damage finishes to inspect hidden conditions.
The standards define a minimum scope. Good inspectors still add judgment, context, and plain-language communication on top of that baseline.