Drilling concrete slabs - went through two reinforcement rods

[Tubie]

Recently made a 170 mm hole for a 160 mm spiral duct. The hole is near the roof truss in the corner. The concrete slab is about 15 cm and feels solid. The house is from 1957. Went through two rebar at the bottom of the slab. I assume it's fine, but I still want to know if there is any risk.

Tried to find similar threads here, there must be many who have done equivalent drilling for ventilation.

Thinking of making the same hole in the other corner of the house.

Thanks for all kinds of responses.

 

[pokasd]

I have no answer unfortunately but wonder what you used to make the hole

 

[Tubie]

I have no answer unfortunately but I'm wondering what you used to make the hole

Company did it. They took the hole from the attic space. The requirement was free height above the hole of about 70-80 cm to access with the hole saw. Took maybe a minute to get through.

 

[Bonzo2000]

Probably done with a core drill. There are both handheld and stand-mounted variants. Usually available for rent where other machines are rented (Cramo, Ramirent etc.)

 

[TechChad]

A bit OT, but core drilling is very beautiful I think.

 

[Marlen Eskilsson]

This is a question for a designer so I am moving the thread to the subforum Building Materials & Construction Techniques.

 

[Tubie]

This is a question for a constructor, so I'm moving the thread to the subforum Building Materials & Building Technology.

Thank you for that! I also noticed that you changed my title

 

[Ohchips]

It's no problem. I've done a lot of hole drilling before during pipe replacements, and many rebar rods have fallen by the wayside, and all the houses are still standing

You can relax

 

[Tubie]

It's no problem. I've done a lot of drilling before on pipe replacements, and many rebar rods have been cut along the way and all the buildings are still standing

You can relax

Thank you for your reply! Exactly the type of answer I wanted to hear. The concrete with large stones feels very solid.

 

[Ohchips]

It certainly looks solid. And that drill hole has only taken a small percentage of all the reinforcement you have, so it's highly unlikely that it will significantly affect the load-bearing capacity of the structure. You can sleep well without worry.

 

[myrstack]

The company did it. They made the hole from the attic. The requirement was a clear height above the hole of about 70-80 cm to access with the hole saw. It took maybe a minute to get through.

Agree with the previous post that it's risk-free. Getting through in a minute sounds like lightweight concrete though, while the picture of both the hole and the core shows solid well-cast concrete, so I assume they had to struggle a bit longer than that.

 

[Tubie]

Agree with the previous post that it is risk-free. Getting through in a minute sounds like aerated concrete though, while the picture of both the hole and the core shows solid well-cast concrete, so I assume they had to struggle a bit longer than that

Thanks for the reply! Ok, maybe 2-3 min Stood below and waited for the drill to come through.