Core Drill Hole Sizes for MEP Work in Dubai

MEP coordinators in Dubai rarely need “a core”. They need a list: this many holes, this diameter, this depth, this floor. The list is what a core drilling crew prices and sets the barrels for. A vague request produces the wrong bit on the truck.

Sizes teams actually ask for

These are common requests, not a catalogue you must pick from. The hole should suit the sleeve, not the other way around.

• About 25 to 52 mm: anchors, small conduits, sample cores
• About 75 to 102 mm: electrical sleeves and smaller plumbing passes
• About 127 to 152 mm: drainage and larger pipes
• About 200 to 300 mm: stacks and HVAC drops, if a single barrel is still practical

Write millimetres on the schedule. “Four inch” and “100 mm” are not always the same allowance once the sleeve and the fire stop are added. If the pipe is 110 mm outside diameter, say you need clearance around 110 mm, and let the crew confirm the barrel.

Clearance, depth and direction

The barrel cuts a hole close to its stated diameter. There is no extra room hiding in the concrete. If the sleeve must pass through with sealant or a fire collar, add that in the request. Depth is the thickness of the concrete, not the length of the pipe. Say whether the hole is vertical through a slab, horizontal through a wall, or angled.

Angled holes and very deep holes take longer and need a rig that can hold the line. They should be separate lines on the schedule, not mixed into “50 holes various”.

When to stop using one barrel

A round hole is right for a round service. A door, a riser and a rectangular duct are not. Those belong to a wall saw or, if the track will not fit, to stitch drilling. Very large round openings can also be stitch-drilled and trimmed, which is sometimes faster than waiting on an oversized barrel.

On a post-tension floor, the size still has to land between tendons. Read core drilling a post-tension slab before the set-out is painted on.

A schedule that can be priced

• One line per diameter
• Quantity, depth, and slab or wall
• Floor, and a note if it is night work
• Post-tension: yes, no, or unknown
• A drawing snippet or a photo with diameters written on it

That is enough for a fixed core cutting quote. Send it with the contact form or on WhatsApp.

Common questions

Get a quote All services