Service
openings.

What service openings are

A service opening is a planned penetration through a slab, wall or partition so that an M&E service can pass through cleanly. The work covers everything from a 25mm core for a condensate pipe up to a 600mm riser for an HVAC duct, and includes the sleeving, fire-stopping coordination and reinstatement that turns a bare hole into a handover-ready opening. Done properly, the M&E or fit-out team arrives to an opening that is the right size, in the right place, with the right sleeve and ready to dress.

Done badly, service openings are where programmes slip — wrong location, wrong diameter, drilled into a post-tension cable, no sleeve, no fire-stopping plan, handed over with slurry still on the slab. We work to the M&E drawing, scan where needed, drill once and hand the opening over clean.

Typical use cases

• HVAC risers and ducts — 100 – 600mm cores for VRF, AHU connections, supply and extract runs through floor slabs and risers.
• Plumbing — soil stacks, mains water, condensate and sprinkler penetrations through floors and walls.
• Electrical and comms — busbar runs, cable tray penetrations, fibre and comms backbone routes through structural fabric.
• Compartment lines and fire-stopping — openings drilled and sleeved ready for mineral wool collars, intumescent mastic or proprietary fire-stop systems.
• Late-stage RFIs and design clashes — services that didn't make the slab pour, missed sleeves, late-revision drawings.

Who it helps

M&E contractors get a clean, drawing-accurate opening with the right sleeve in place — no chasing the structure team for a second pass. Fit-out contractors get penetrations they can dress straight away without having to make-good around a ragged hole. Main contractors get an opening that lines up with the fire strategy and doesn't trigger a clash with structure or post-tension. Facilities teams retrofitting M&E into existing slabs get a hole through reinforced concrete that doesn't shake the rest of the building.

What to send for a fast quote

• M&E drawing or service schedule with grid references.
• Hole diameter (per service) and number of openings.
• Wall, floor or slab thickness and reinforcement notes.
• Sleeving spec (or "tell us what's appropriate").
• Fire-stop strategy if known — compartment lines, fire ratings.
• Working hours, access route, occupied / live areas.
• Programme date or deadline.

If you only have a sketch and a postcode, send those — we'll come back with the questions worth asking. Full quote checklist.

Safety, dust and clean-work notes

Penetration work is often inside occupied buildings — offices kept open, retail trading next door, hospitals with patients on the floor below. We work wet by default with slurry contained and removed, and dry with M-class HEPA extraction where wet is not an option. Drop sheets, slab protection and clean-down are scoped up front. Where the compartment line matters, openings are sleeved and handed over ready for the fire-stopping contractor — we coordinate with the spec rather than freelancing on it. Scanning is done before the rig is set on any slab where reinforcement, services or post-tension matter.

Related services

• Core drilling — diameters, depths and the drilling method behind every opening.
• Diamond drilling overview — the kit and substrate range.
• Concrete cutting — when an opening is bigger than a core barrel can do.
• Specialist works — stitch drilling for rectangular openings, restricted-access work.
• Rapid & out-of-hours — for the openings that have to be done overnight.