01 / REVIEW
Measure the actual condition
Record where and when an opening was observed and how it was measured. Note the direction of travel and whether the condition is between boards, at a transition or around another component.
02 / REVIEW
Keep limits and recommendations separate
An applicable maximum opening criterion is not automatically the correct installation gap for a wood product. Product movement, installation instructions and the governing design must be coordinated by the responsible team.
03 / REVIEW
Track change
For existing work, retain repeated observations with location and condition. Ask the designer or owner to evaluate changes rather than converting one measurement into a site-wide approval.
Map openings in the installed route
The spaces between boards are only some of the openings a visitor encounters. Include access covers, drains, perimeter details and transitions to other surfaces. Record where each occurs and the direction people travel across it. A single average board gap cannot describe every condition.
Use the project’s established requirements and accepted details as the review basis. This observation exercise does not set a universal permissible opening. Record measurements with their location, date and surface condition rather than treating a photograph as a scale drawing.
Give each condition its own reference
Scroll sideways to read all columns. Keyboard: focus the table and use the arrow keys.
| Condition | Record |
|---|---|
| Field board joints | Location and stated measurement method |
| Board ends | Joint and supporting detail reference |
| Access covers | Perimeter and opening arrangement |
| Drainage interface | Grate or slot identity and accepted detail |
| Material transition | Adjacent surfaces and any change in level |
In a fictional promenade, the field boards are consistent but a removable cover creates a different perimeter opening. That cover needs its own review. Changing the field-board spacing would not resolve the cover detail.
Where an observation raises a safety or accessibility concern, follow the owner’s process for managing access and obtaining qualified review. Keep the original observation and the resulting action together so the next inspection can revisit the same location.
Understand the criterion without turning it into a milling instruction
Under ADA §302.3, as explained in the Access Board’s surface guide, openings must prevent passage of a ½-inch-diameter sphere. Elongated openings are generally oriented with their long dimension perpendicular to dominant travel. The guide also addresses areas without a dominant flow and routes that bypass openings. Have the applicable condition established for the project.
That criterion describes the accessible surface condition. It is not a recommendation to install wood boards at a ½-inch gap. Product instructions, moisture-related movement, connection geometry and the project detail must be coordinated. Do not use a regulatory limit as the target setting on the installer’s spacer.
Record enough information to repeat the observation
Scroll sideways to read all columns. Keyboard: focus the table and use the arrow keys.
| Record field | Why it matters |
|---|---|
| Segment and feature ID | Returns the next observer to the same location |
| Opening being measured | Distinguishes a field seam from a cover or drain |
| Direction and measurement method | Explains which dimension the record describes |
| Date and surface condition | Keeps a one-time observation in context |
| Observed value and units | Preserves the measurement without rounding away a concern |
| Instrument or photo reference | Lets the reviewer find the underlying evidence |
| Reviewer response | Separates the observation from the decision |
Use a separate entry for each condition that differs. If only one end of a cover can be inspected, record that limit. Do not fill the other entries by assuming symmetry. Photographs help locate the opening, but perspective and an unreadable scale can prevent reliable measurement from the image alone.
Fictional example: two observations at the same cover record different conditions after adjacent work. Preserve both dates and the intervening work reference. Replacing the first entry with the newer one would erase the information the reviewer needs to understand the change. The location log supports this sequence while keeping any acceptance decision separate.
A public-route planning scenario
Concept example: the sample panel is measured on receipt and again during review. Both observations stay in the record, alongside the product instructions and the designer’s decision.
Use the result
Keep the completed review with the relevant project record. Assign unresolved items before relying on a conclusion. If the material, condition or document changes, revisit the affected questions.
Boardwalk plannerTechnical references
General background for the subject. Project worksheets and fictional situations are original review aids, not official agency forms.
Access Board: floor and ground surfaces