Concrete drilling may seem like a part of a big construction plan but when it gets delayed the trades that come after also get delayed. A missed access window, a drawing or an unresolved structural question can stop work from starting on the planned day.
Even though the drilling itself takes a short time, bad preparation can cause delays in many connected activities. The best way to avoid this is to treat drilling as a dependency, in the wider programme not as a separate task.
The sections below focus on where delays typically start and how to remove them early.
A Delay That Started Before the Drill Arrived
Picture a six-storey fit-out. The electrical contractor is due to pull cable through a run of openings in a floor slab on Monday. The drilling team is booked for the previous Thursday. When they arrive, the engineer’s approval for two of the openings, which sit close to a transfer beam, has not been issued, and one corridor is blocked by stacked plasterboard. Half the openings are drilled, the rest wait, and the electrical crew starts a week late.
None of this is a drilling problem. Each cause was visible days earlier and none was checked. This scenario is illustrative, but most real delays follow the same pattern.
Confirm the Requirements and Information Early
Before a date is agreed, the team should have the following in hand:
- Number, location, diameter and depth of each opening
- Concrete type and thickness, and whether reinforcement is present
- The purpose of each opening and the date it is needed
- Drawings that reflect current site conditions, not an earlier revision
- Any engineering review or approval required for openings that affect structural elements
Approvals deserve particular attention. They can take longer than the drilling itself, and a location that has to move after the team arrives delays both the drilling and the trade waiting for the opening. Where an approval is still outstanding, say so on the schedule rather than assuming it will arrive in time.
Check for Reinforcement and Concealed Services
Concrete can hide reinforcement, post-tensioned elements, conduits and other services that are invisible from the surface. Where appropriate, scanning or other investigation should be part of the preparation stage, with the results reviewed before drilling is confirmed.
The aim is not just to find somewhere a hole can go, but to establish whether the proposed position is suitable and whether changes are needed. Finding a conflict during preparation costs a revised marking-out. Finding it with the crew on site costs a stopped job.
Coordinate Access, Power and Water Before Mobilisation
Sites change constantly. A route that was clear when the work was planned may later be filled with materials, temporary works or another contractor’s equipment. Before mobilisation, confirm:
- How equipment will reach the work area, where it can be unloaded, and whether lifting is needed
- Available working space, including height or confined-space constraints
- Power and water supply, and working-hour restrictions
- How slurry, drilling waste and removed cores will be managed
Resolving these in advance makes the start of the work far more predictable, and it is often the cheapest delay prevention available.
Work Backwards From the Follow-On Trade
Openings are usually needed for pipework, ductwork or electrical services, so the drilling completion date directly affects another contractor. A useful approach is to start from the follow-on activity and work back:
- When does the next trade need the opening?
- When must drilling be finished for that to happen?
- What must be ready, cleared or approved before drilling can start?
- What inspection or handover is needed in between?
It helps in highlighting the limitations that would be overlooked during planning of the drill alone. It also ensures accountability since there is an owner for each task and date attached. Early involvement of specialist contractors can also help identify construction risks, sequencing issues and resource requirements before they affect the programme, an approach reflected in UK government guidance on early contractor involvement
Keep a Fallback Work Area
Programmes rarely stay fixed. Access changes, another contractor finishes late, or a service route is revised. The most effective protection is a fallback.
Before mobilisation, identify an alternative area where the crew can work if the planned zone becomes unavailable, for example a second floor, a different riser or another set of openings that are already approved and clear. Agree in advance who can authorise the switch and how the follow-on trades will be told.
This turns a stopped job into a re-ordered one. A single blocked corridor then costs hours rather than days, and the crew’s time is not lost. It works best when the fallback area has the same preconditions already checked: approved locations, scanned slabs, power and water available.
Choose a Method That Suits the Site
The process must meet the requirements: diameter and depth thickness of concrete, reinforcement orientation number of holes, required precision and any environmental limits. Diamond drilling is the technique often used to make holes in reinforced concrete. However the choice of equipment and method depends on site conditions, such, as water and slurry management.
If a project is complicated and has holes to be drilled or if access is limited or the schedule is tight I would say it is best to talk to the drilling contractor before starting.They will be able to bring up the issues with methods, extraction, and working space, which will be easier to solve in advance.
Build Mobilisation Into the Programme
The planned window should cover more than the drilling. Equipment has to be transported, access confirmed and the area prepared. Specialist operatives and equipment may also carry lead times.
On large schemes, resourcing can become part of the delivery strategy. On the Chelsea Barracks redevelopment, for example, CA Drillers’ published case study notes that an on-site office and equipment storage facility was established to keep manpower and specialist equipment available to the project. Few jobs need that level of set-up, but the principle applies at any scale: mobilisation and resources belong in the programme, not after it.
Pre-Drilling Delay Check
Before confirming the drilling window, the team should be able to answer yes to each of these:
- Information: Are locations, drawings and approvals confirmed, and has structural review been completed?
- Site: Has scanning been considered, access confirmed, and power, water and working space arranged?
- Programme: Is the follow-on trade ready? Has enough time been allowed for mobilisation?. Is a fallback area clearly identified?
- Communication: Does everyone understand what is being drilled, where it is happening, when it will take place and who is responsible for each part? On multi-floor or phased work, a marked-up drawing or shared schedule helps stop finished openings being overlooked.
If several answers are unclear shortly before mobilisation, the activity probably isn’t ready to start.
Conclusion
The reduction of drilling delays mainly revolves around planning and coordination. It is all about having clear requirements, structural knowledge, investigation, accessibility, contingency, and proper communication with the subsequent trades.
The useful question is not simply “When can the concrete be drilled?” It is “What needs to be ready before drilling, and what happens immediately afterwards?” Asking it early, and involving specialist diamond drilling contractors when the job’s complexity calls for it, helps stop a small activity becoming a wider programme problem.
