Planning & documentation
Reviewing Under-Slab Services Before Steel Building Placement
Coordinate under-slab services, sleeves, testing, survey references, and record evidence before concrete conceals steel building interfaces.
Define the condition and its scope
Under-slab review preserves the location and acceptance evidence of concealed service work.
Foundation coordination brings the building-system geometry, site information, slab requirements, and construction sequence into one interface. The concrete contractor needs more than a general steel layout, while the erector needs evidence of the accepted condition rather than an assumed fit. Use the responsible designers' current foundation and building documents together. Keep dimensions, elevations, reactions, sleeves, edges, and equipment locations traceable to their source. Coordinate cold-formed wall bases as well as primary steel supports when they share the slab or perimeter detail.
References: Steel erection: site layout and construction sequence · Commissioning documents: process, contents, and acceptance
Gather the inputs before deciding
Assemble current routing, sleeves, drainage points, electrical pathways, foundation interfaces, and required service tests. Compare locations with slab joints, equipment, and building grids. Assign each concealed record to its author and reviewer. Identify information that must be preserved before placement, including coordinates or dimensioned references. A photograph can support the record but cannot reliably locate buried work if its position and orientation are unknown.
- Current service routing plan
- Sleeve and foundation conflicts
- Required service test records
- Located concealed-work documentation
References: Steel erection: site layout and construction sequence · Commissioning documents: process, contents, and acceptance
Set observable handoff deliverables
Later photographs without coordinates may not locate a buried service for future alterations.
| Input | Evidence to keep with it | Review status |
|---|---|---|
| Current service routing plan | Located current service plan | Identify reviewer and written decision |
| Sleeve and foundation conflicts | Accepted conflict and sleeve details | Identify reviewer and written decision |
| Required service test records | Test and concealed-location records | Identify reviewer and written decision |
Sequence review and release
Resolve routing conflicts with the responsible disciplines while the services remain accessible. Obtain required testing and inspection dispositions before concealment. Record accepted locations against survey or building references. Update shifted drains or sleeves across service and slab documents. Brief the placement contractor on remaining protected areas. If a late change appears, use the required review process instead of moving the service around an unresolved support.
- Locate current service routing plan in the current record.
- Compare sleeve and foundation conflicts with the table's evidence.
- Document the decision: Preserve required service acceptance and location records before concealment.
Worked project coordination example
A floor drain is moved during coordination. Before placement, the service contractor updates the route record, confirms required testing, and coordinates the revised location with slab and equipment drawings.
Apply the stated release decision to the case: Preserve required service acceptance and location records before concealment. The responsible team determines acceptance for the actual project and records any condition that still requires resolution.
Keep a closeout record another team can use
Deliver a located concealed-services index with tests, inspection references, accepted changes, and installation records. Distinguish planned routes from verified installed routes. Identify unfinished service connections or deferred testing separately. Future alteration teams need records that allow professional investigation before drilling or cutting. The handoff should explain its verification limits and not portray a preliminary routing plan as a complete record of everything beneath the floor.
For this issue, include test and concealed-location records in the handoff. If review remains pending, identify the dependent work and its owner; do not present the record as a completed technical acceptance.
Common questions
Can a visual check replace required service tests?
No. Follow the project and authority requirements for the installed service.
How should current service routing plan be documented?
Preserve required service acceptance and location records before concealment. Retain located current service plan and check that the decision reached the team performing the dependent work.
Sources & further reading
Use the current documentation for the exact product and project. Source links do not imply a partnership or endorsement.
- Steel erection: site layout and construction sequence Occupational Safety and Health Administration
- Commissioning documents: process, contents, and acceptance Whole Building Design Guide
Prepared with AI assistance. Linked references require current project-specific review. How these guides are prepared.
Prepare a supply inquiry
- Record the project drawing or detail and the specified product, profile, or system.
- List the complete configuration, physical units, quantities, and cuts per piece.
- Request current manufacturer documents; confirm compatibility, price, and availability before ordering.
- Obtain the responsible professional's review for loads, code requirements, or installation.