Concrete Cutting and Coring

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Doors, windows, pipe sleeves, stairwells and new drains all mean cutting into concrete that is already there. Concrete cutting and core drilling are specialist jobs, done with diamond blades and bits. ConcreteSlab.co.za is a free quote service. You fill in one form and we pass your request to independent cutting and coring contractors in your area, who quote you directly. We do not cut, drill or install anything ourselves. There is no fee and no obligation, and you can compare contractors before you decide.

Cutting methods and what each one does

Different jobs call for different machines. A good contractor picks the method that suits the thickness, the reinforcing and the space available.

Core drilling: round holes from about 25 mm up to 600 mm or more, for pipes, cables, extraction ducts and anchor holes.
Wall sawing: a track-mounted saw cuts straight openings in walls for doors, windows and lift shafts.
Floor sawing: a petrol or electric saw cuts slabs, trenches and control joints.
Wire sawing: a diamond wire cuts very thick or awkward concrete in sections.

All of these use diamond tools. They cut through steel reinforcing as well as concrete.

Why saw instead of breaking

A saw gives a clean, straight edge and little vibration. A jackhammer shakes the whole structure and leaves ragged edges that need patching. For openings in an existing building, sawing is nearly always the better choice.

Saw-cut joints are also used in new slabs. Concrete shrinks as it cures, and a cut made within the first day or two guides the crack into a straight line. A slab cut this way looks neater and is easier to seal than one that cracks at random.

Noise, dust and slurry are lower with wet cutting. Dry cutting is used only where water would cause damage, and then with dust extraction.

What to check before cutting starts

Cutting into a structure can weaken it. Walls, beams and suspended slabs carry load, and an opening may need a lintel or a header designed by an engineer. In sectional title and apartment blocks you may also need the body corporate's consent.

Have the reinforcing, cables and pipes scanned before you core or cut.
Ask whether the contractor will be on site with the correct permits.
Make sure water and power are available, or tell the contractor a generator is needed.
Plan for slurry removal, especially indoors.

Post-tensioned slabs must never be cut without the engineer's drawings.

What affects your quote

Many people search for concrete cutting machine hire or the cost per hole, but each job is different. We never give prices here. Contractors will look at:

The number, diameter and depth of the holes, or the length and depth of the cuts.
The thickness and the amount of reinforcing steel.
Access, height and working space.
Water, power and slurry removal.
Travel distance, and a call-out minimum for small jobs.

Clear details help contractors quote accurately.

Comparing quotes for concrete cutting and coring

The lowest figure is not always the best deal. When your quotes arrive, check:

Specification: the thickness, the concrete strength in MPa, the steel and the membrane, so every quote is for the same work.
Preparation: excavation, sub-base compaction, shuttering and who removes spoil and rubble.
Concrete and access: ready-mix or site-mixed, whether a pump is included and any part-load or waiting charges.
Finish, curing and guarantee: the surface finish, how long it will be cured, where joints are cut and what guarantee covers the work.

What to include in your request

Number and size of holes or the length of the cuts
Thickness of the slab or wall, if you know it
Whether the work is indoors, on a high floor or in a tight space
Access to water and power on site
Any plans or an engineer's detail for structural openings

Frequently asked questions

Does ConcreteSlab.co.za cut or core concrete?

No. ConcreteSlab.co.za is a free quote service. You send one request and we pass it to independent concrete cutting and coring contractors near you. They contact you directly with a quote. We do not cut, drill or install anything, and we do not charge you or the contractors for the introduction.

How far can a contractor core or cut through concrete?

Core bits and wall saws handle slabs and walls a few hundred millimetres thick as a matter of course. Thicker concrete may need wire sawing or a larger machine. Tell the contractor the thickness and whether there is steel, and they will say what is practical.

Will cutting damage pipes or cables inside the concrete?

It can. Diamond tools cut through anything in their path. Ask for the concrete to be scanned first, check the building plans and mark out services. A careful contractor will not start until the position is confirmed.

Do I need an engineer before cutting an opening?

If the wall or slab carries load, yes. An engineer can design the lintel, header or trimming steel needed around the new opening. Non-structural cores for small pipes are usually simpler, but ask your contractor if you are not sure.