Soil is very compact and potentially rocky, I need to get down several feet. I have at least 5 footer holes to dig.

Thinking of buying a cheap corded 1/2 drill and 18 inch long auger bit set and considering throw away - doesn't matter if I destroy.

This would be for loosening soil. My understanding is that a full size auger bit will not work on anything but a gas-powered drill.

Will a wood auger bit work in this scenario?

I would loosen the soil with the drill and shovel out.

  • How much clearance is there between the ground and the structure above? – MTA Jul 16 at 16:29
  • clearance varies in the spot i need to really go down several feet (and build a 2 x 2 foot large footer), i have 4+ feet there. In one of the other spots, I only have 2 feet. and in the worst, 1 foot clearance. – House DiY Jul 16 at 16:32
  • Yikes! I'm all for DIY, but sometimes... It might be better to hire this part out and let someone else break his back! – FreeMan Jul 16 at 16:56
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    Unlikely, but worth asking---can you open the floor above the footing locations? – isherwood Jul 16 at 19:39
  • In one spot, yes I can open the floor up - it's just 4x8 on top of rafters – House DiY Jul 18 at 4:55

I don’t think a drill and auger will be of any use.

I did a job like yours many years ago, providing much of the grunt work for a much older, but more experienced workman.

Step one is to dig a trench in the crawl space deep enough to stand without stooping (much). The trench goes adjacent to (within reach of) the spots where you want the footings. Branch the trench as needed. Use a pick and shovel. To remove the tailings efficiently, fill a container about the size of a U.S. Mail bucket, drag it out and dump it. A pick and shovel can deal with hard soil and rocks. A drill and auger, not so much.

Step two is to dig out the sites where the footings will go using a pick and shovel, while standing in the trench.

Step three is to build forms for the footings.

Step four is to mix your concrete outside, fill buckets, carry via trench, and dump.

Safety note: if you need electricity down there, make sure to get it from a GFCI protected outlet.

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    I've gotta ask... how deep was the trench that you were able to swing a pick with any effectiveness? A shovel can (very slowly) be pushed through the dirt to (very slowly) scrape it away, but a pick really needs to be swung, does it not? – FreeMan Jul 16 at 16:58
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    @FreeMan Not really -- it's not like you're a prisoner breaking rocks. A pointy pick can work effectively against hard soil by lifting it a bit and just letting it drop. In the case of the job I worked on, the trench started outside, so I was already standing below ground level at the point that I got under the house. It just makes the whole job less punishing if you can stand while you work. As I recall, the trench was about four feet deep and the underside of the house was about two feet above the soil. – MTA Jul 16 at 17:08
  • Makes sense. Plus, I guess, the pointy end of the pick can be dropped and pulled toward you to loosen the soil so it can be scooped out. – FreeMan Jul 16 at 17:28
  • trench not possible due to location and size. Getting drill bits tonight and will test with battery drill. Trip report later. It doesnt have to be awesome, just loosen the soil and destroying the bits is ok. And I am a prisoner digging this footer :) – House DiY Jul 16 at 17:42
  • You will need a trench of some scale at LEAST for the place where you only have 1 foot clearance but need to dig. Need not be standing depth, but you won't be able to work effectively in that little space. Even prisoners digging escape tunnels need some space to dig in. How little you can get away with might vary with how young and/or flexible you are, but 1 foot is hard enough to wriggle through, much less dig from - or place concrete from. – Ecnerwal Jul 16 at 17:47

You need an electric or pneumatic chipping hammer:

enter image description here

There are various bits you can use:

enter image description here

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  • Moderate success with the rotary hammer, expect more results this week. Also see small-cabin.com/forum/2_4468_0.html "On the other hand, the rotary hammer and chisel were very effective against a clay and gravel mix. A shovel barely made a dent in it but the rotary hammer chewed it up no problem." – House DiY Aug 5 at 6:41

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