Core
drilling.

Looking for the method itself? See diamond drilling.

What core drilling is

Core drilling cuts a clean, round hole through reinforced concrete, brick, stone, masonry and similar substrates using a diamond-tipped barrel rotating under water. Unlike a hammer drill or an SDS, there is no percussive impact — the diamond grit grinds the material away. The result is a tight-tolerance hole with no spalling around the edge, no shock to the surrounding slab, and a solid extracted core that can be set aside or removed.

It is the standard method any time the hole needs to be accurate, the substrate is reinforced, or vibration matters — live retail, occupied offices, hospitals, listed buildings, post-tensioned slabs, residential party walls. We cover diameters from 12mm dowel bars through to large-diameter risers, and depths from a few centimetres up to roughly 3m as standard.

Typical use cases

• M&E penetrations — cores for ductwork, soil stacks, comms, electrical risers and HVAC runs through floors and walls.
• Sample extraction — concrete cores for compressive testing, aggregate analysis or carbonation depth checks.
• Piling and ground investigations — probe holes through pile caps, ground beams and raft slabs.
• Anchor and dowel bars — accurate, repeatable holes for structural connections, balustrade fixings and starter bars.
• Drainage — through-wall cores for new gullies, soil pipes, AAVs and condensate runs.
• Test cores for surveys — investigation holes during refurbishment, demolition feasibility and party-wall work.

Who it helps

Most of the briefs come from M&E contractors threading services through occupied buildings, fit-out contractors opening up risers and partitions, and main contractors planning structural openings around the rest of the programme. Refurbishment teams use us for sample cores and for opening up old slabs for new services. Facilities and site managers call us in for one-off jobs — a leaking riser sleeve, a missed soil stack, an anchor pull that needs to be redone before sign-off.

Whatever the route in, the work pattern is the same: send the brief, get a price, book a slot, get a clean hole back.

What to send for a fast quote

• Site postcode and floor level / access route.
• Required diameter (in mm) and number of cores.
• Substrate — concrete, brick, stone — and slab or wall thickness if known.
• Through-cores or blind, vertical / horizontal / overhead.
• Reinforcement: rebar density, post-tension, services nearby.
• Working hours, deadline or permit window.
• Drawings, sketches or phone photos — even a rough phone snap helps.

Half of that is enough to come back with a price; the rest tightens it up. Full quote checklist here.

Safety, dust and clean-work notes

Wet drilling is the default — water cools the diamond barrel, captures the slurry at source and keeps respirable silica out of the air. Slurry is contained on site with squeegees, sumps or vacuum extraction depending on access, then removed or bagged out as agreed up front. Where wet drilling is not an option — live retail, sensitive finishes, IT cabinets directly below — we run dry with M-class HEPA extraction at the barrel. RAMS, COSHH and any required permits issued before the crew mobilises. Where scanning is needed it happens before the rig is set, not after.

Related services

• Diamond drilling overview — methods, equipment and substrate range.
• Service openings — M&E penetrations, sleeves, fire-stopping.
• Concrete cutting — when a saw cut is the right tool instead.
• Specialist works — stitch drilling, restricted access, working at height.
• Rapid & out-of-hours — when the slot is the constraint.