borehole in KT24 (65)

A core drill removes a cylindrical piece of material, while a twist drill removes all material, creating a hole and ejecting waste out of the top.

Twist drills are for general-purpose drilling and can easily cut through materials like plastic, wood and metal.

Core drills are for more specialised uses, such as geological sampling, and can cut through harder surfaces, like stone and concrete.

Depending on the material you’re drilling and the depth of the hole, core drilling can take minutes or hours. In a construction setting, it may take only a few minutes to drill a hole 30cm deep, but there’s also preparation and clean up time to consider, which can add another hour or so.

Drilling this same hole in a particularly hard surface, like reinforced concrete, could take roughly 30 minutes to an hour. Speak to a core drilling expert to find out how long it might take in your situation.

A typical core drill bit is about 14” long, but you can get them in sizes exceeding 24” for deep-drilling projects.

In industrial and geological applications, core drills can reach depths of thousands of feet, which is usually achieved by attaching multiple drill rods together.

Essentially, you can drill as deep as you need to go if you get the right attachment for your drill, but extremely deep holes require specialist equipment.

Wet core drilling and dry core drilling are two commonly used types.

Wet drilling involves using water to keep the drill bit cool and control dust, while dry drilling doesn’t use water, either because the material doesn’t require it or it could create a mess.

Hard and soft drilling are two more examples.

Hard drilling usually refers to drilling materials harder than sandstone, whereas soft drilling refers to drilling materials like soil or tarmac.

Depending on the material being drilled, a typical diamond drill bit lasts for around 200 to 250 holes.

If the drill is used for hard materials like reinforced concrete, this number drops significantly to roughly 50 holes or potentially fewer.

Using cooling methods when drilling can also help you get more from your drill, as it protects it from overheating and damage.

Be sure to regularly inspect and maintain your drill bit to extend its life as much as possible. If you notice yellow, brown or black marks around the tip, this means it’s been overheated, which you should try to avoid.

As a rough estimate, you could expect to pay around £540 per day for core drilling services, which includes about £400 for labour and £140 for materials.

For specific advice on how much core drilling might cost you, check out this helpful guide.

We recommend contacting a tradesperson for accurate quotes.