Coordinate the penetration before drilling
A circular hole is often part of a larger services installation. Its position, size and angle must suit the design and the structure through which it passes. The concrete core drilling service supports penetrations for plumbing, electrical and mechanical services, but it does not decide the route or approve an alteration to the building.
Use a coordinated penetration schedule instead of separate informal marks from several trades. Give each hole a reference, drawing location, diameter, depth and purpose. Confirm the drawing revision and who can approve a location change. A sleeve, insulation or fire-stopping system may need a larger opening than the pipe alone.
Check the concrete and concealed conditions
Provide structural drawings, known reinforcement or tendon information and available service records. A slab may contain electrical conduits, plumbing or post-tensioning that cannot be inferred from its surface. The project team should determine the investigation, scanning and engineering review needed before the final locations are released.
Agree what happens when the nominated position conflicts
If investigation identifies a conflict, the installer and designer should coordinate an alternative rather than letting the drilling crew shift the hole without approval. Small movements can affect falls, clearances or other services. Record the changed location in the schedule so the completed work can be reconciled with the design.
Plan for both sides of the penetration
Access beneath a slab or behind a wall affects containment and retrieval of the core. Tell the contractor whether the area below is occupied, contains sensitive equipment or is inaccessible. Water, slurry and falling material need controls suited to those conditions. A clear top surface does not mean the underside is ready for work.
High workfaces, overhead drilling and congested plant rooms can require separate access arrangements. Explain available platforms, building load limits and routes for equipment. Ask who supplies power and water and where collected slurry is taken. Do not assume it can be discharged into a nearby drain.
Distinguish drilling from the finished penetration
Core drilling creates the opening. Sleeves, pipe installation, waterproofing, fire stopping and acoustic sealing may be carried out by other trades. Identify the specified reinstatement system and the contractor responsible for it. A completed hole should not be presented as a completed fire-rated or watertight assembly.
Agree tolerances and records before work starts. The completed hole schedule should identify actual locations and any deviations requiring acceptance. If an unused opening needs repair, obtain the designer’s requirement rather than assuming a general patch is adequate for every structural or fire-resistance condition.
Core drilling enquiry checklist
- Hole references, dimensions, angles and drawing revisions.
- Structural information and investigation requirements.
- Access to both faces and occupancy beneath the work.
- Water, power, slurry collection and working hours.
- Responsibility for sleeves, fire stopping and waterproofing.
- Acceptance tolerances, completion records and unused-hole repairs.
Prepare a coordinated drilling package
Discuss core drilling for your concrete penetration schedule after the design and trade interfaces are identified.