# Need to drill through terrazzo floor



## miamicuse (Nov 13, 2011)

I need to drill four 3/16" hole through a terrazzo floor to anchor something to it.

No, it will not be anchoring to the terrazzo, but to the concrete slab under it.

I tried a Tapcon bit which chews through concrete no problem and it's hardly making a dent on this terrazo. Even with slower speed and a squirt bottle after a few minutes it's not cutting through.

Do I need a diamond coated specialty bit? Hate to buy one just for four holes.

This is a new Tapcon bit too so it's not a worn bit, although it may be worn now.


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## mako1 (Jan 7, 2014)

You need a diamond bit.You have the right idea with the water but the bit your using won't cut it.Make sure you lift the bit in and out every so often to clear the hole while drilling.A 3/16 diamond bit should not be to much.
I use Tapcons all the time but the bits that come with the screws aren't the best.I buy the Tapcons in bulk and use Millwaukee bits in a hammer drill.


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## stadry (Jun 20, 2009)

diamond coring bit to fit a 4" grinder - find 'em on eBay,,, LOTS of wtr, too :thumbsup:

irc


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## mako1 (Jan 7, 2014)

Why would they need a coring bit for a 3/16" hole?And why would you want to use a drill on a angle grinder in place of a hammer drill?


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## joecaption (Nov 30, 2011)

If your trying to use a regular drill not a hammer drill that's the problem.
No need for a diamond anything.
Sure the bits not worn out?


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## miamicuse (Nov 13, 2011)

It is a BRAND NEW bit as stated in the original post, used on a hammer drill in a hammer mode.

Tested bit on regular concrete and just bored a 3/16" hole 4" long in about 10 seconds.

Using the same unworn new bit on this terrazzo for 10 minutes dented it about 1/8".

I do have a Dremel with a 3/16" diamond bit, but I am not sure that "hobby" tool will work here.


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## stadry (Jun 20, 2009)

why ? 2 reasons: 1st, its the correct tool / method; 2nd, i don't want to cause any damage to an expensive floor,,, we get paid to do work - NOT cause damage,,, that's why we OWN the right tools,,, if we didn't need them to do our work, we would rent just as genl contractors do,,, genl contractors use edco conc saws but you'd never see any pro's behind 1.

traditional terrazzo is white cement & modern is epoxy both w/decorative aggregate + labor intensity,,, its there because someone paid beau coup $$$ for a decorative floor that would outlast the roof,,, using a hammer drill or ANY rotary hammer/percussive equip/bit isn't correct imo,,, as the op's discovered, conc has a lower strength than terazzo,,, IF you have a dremel AND a bit, what's the delay ? just remember - lots of water - that will cool the diamond segments + flush away the 'swarf',,, using a hammer drill, etc, risks damage to the flooring in my view & exposes 1 to a much liability,,, have you ever tried to repair terrazzo OR paid an artisan to do it ? hammer drill, my patoot 

irc


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## miamicuse (Nov 13, 2011)

itsreallyconc said:


> why ? 2 reasons: 1st, its the correct tool / method; 2nd, i don't want to cause any damage to an expensive floor,,, we get paid to do work - NOT cause damage,,, that's why we OWN the right tools,,, if we didn't need them to do our work, we would rent just as genl contractors do,,, genl contractors use edco conc saws but you'd never see any pro's behind 1.
> 
> traditional terrazzo is white cement & modern is epoxy both w/decorative aggregate + labor intensity,,, its there because someone paid beau coup $$$ for a decorative floor that would outlast the roof,,, using a hammer drill or ANY rotary hammer/percussive equip/bit isn't correct imo,,, as the op's discovered, conc has a lower strength than terazzo,,, IF you have a dremel AND a bit, what's the delay ? just remember - lots of water - that will cool the diamond segments + flush away the 'swarf',,, using a hammer drill, etc, risks damage to the flooring in my view & exposes 1 to a much liability,,, have you ever tried to repair terrazzo OR paid an artisan to do it ? hammer drill, my patoot
> 
> irc


I hear you about drilling holes and damaging a good floor.

However in my case, I am replacing a rotted bottom plate in a laundry room. Property was in foreclosure for years and sat vacant abandoned, during which time there must have been some vandalism as the washer dryer were removed and copper pipes ripped out caused a flood. The bottom plate was damaged and rotted.

I removed the bad bottom plate and found terrazo under it. Original house must have been all terrazo floor would have been nice to keep it but now, mostly marble, porcelain tiled over. The bottom plate was put over the terrazo and someone shot nails into it so its a bit damaged already. So that's why I am securing a new PT plate there with tapcon screws.


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## stadry (Jun 20, 2009)

thanks, paul harvey - nice to hear the ' rest of the story ' 

irc


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## rustyjames (Jul 20, 2008)

I would try a more robust hammer drill and a better bit.


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## Canarywood1 (May 5, 2012)

miamicuse said:


> I hear you about drilling holes and damaging a good floor.
> 
> However in my case, I am replacing a rotted bottom plate in a laundry room. Property was in foreclosure for years and sat vacant abandoned, during which time there must have been some vandalism as the washer dryer were removed and copper pipes ripped out caused a flood. The bottom plate was damaged and rotted.
> 
> I removed the bad bottom plate and found terrazo under it. Original house must have been all terrazo floor would have been nice to keep it but now, mostly marble, porcelain tiled over. The bottom plate was put over the terrazo and someone shot nails into it so its a bit damaged already. So that's why I am securing a new PT plate there with tapcon screws.




When the terrazzo was installed they probably used granite for the chips, more than likely that's why your having problems drilling it,like IRC said get a diamond core bit.


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## MrTerrazzo.com (Dec 31, 2014)

*terrazzo*

how do you know there is a slab under the terrazzo?. every single terrazzo floor i have ever seen which is in the thousands have no slab, the terrazzo is the slab ! and it is usually 4 inches to 6 inches thick... that is how the homes that have terrazzo were built. the terrazzo is the slab and the interior partitions are not load bearing the roof is supported by the exterior walls. hence when you knock down an interior wall there is terrazzo underneath and on the stoop and on the foyers....

so did you have your terrazzo floor recently poured over a slab ?? if so you might not even have cement based but an epoxy based terrazzo 

as far as drilling just use a hammer drill and lean on it lol......


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