Drilling into span crete

by Lori
We have an earth shelter and would like to add lighting. Our ceilings are span crete and we wonder if we dare to make holes to put can lights in? Or would that weaken the span. They would be placed in the hollow core - probably 4 in a 12 foot section. I hate track lighting and am hoping to avoid it!! This remodel is wearing me out!!
  7 answers
  • Hope Williams Hope Williams on Mar 31, 2015
    Do not drill span Crete!!!!!! Use the 3M sticky hooks to hang maybe rope lights or string lights. Just don't drill!
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  • Moxie Moxie on Mar 31, 2015
    You can drill hollow core but you can't damage the reinforcing. If you dont know where it is...will be hard to avoid unkess you have or csn get shop drswing from product mfg or you can xray the slab to verify where it is to avoid. It us not cheap but is possible
  • Mcgypsy9 Mcgypsy9 on Mar 31, 2015
    How high is the ceiling in your earth shelter? Would it be possible to add another ceiling below the existing and putting your can lights in that? I hate track lighting too. If you can't do that maybe make a shorter new ceiling and add light spot lights into it. Another idea would be to roll rope lights into a coil shape and secure them to the ceiling. Let us know what you decide : )
    • Lori Lori on Mar 31, 2015
      @Mcgypsy9 Our ceilings are 8' We aren't able to drop that ceiling any! I think if we drill in the hollow cores we should be o.k. We are looking at can lights - we have drilled small holes and fished electric wire through them, but never the size of a can light. We are getting older - need more light!!
  • Mcgypsy9 Mcgypsy9 on Apr 06, 2015
    LOL I know what you mean about getting older! Same here! I think I would try the rope lights first. Just coil them up and either tie them together or use some sort of glue between the coils...then just find some hooks or something to attach them. Anyway...let us know if the can lights worked!
  • Andrew Andrew on Apr 14, 2015
    I have large 6" holes drilled in numerous places in our spancrete because it was originally, and still is in most places, used as part of the HVAC system. They cut holes in the bottom in one place for the input and then along the wall at the other end on top for the vent. I also asked the engineer that did the door calculations for some new doors we are cutting below the spancrete for a remodel if we could do cut new holes for spancreate and he said that would be fine as long as we stay away from the edges and the center support ridges.
    • Lori Lori on Apr 14, 2015
      @Andrew Thanks Andrew! We will probably use the hollow cores to place our can lights! As durable as our house is - it comes with some challanges! Thanks again!
  • Andrew Andrew on Apr 14, 2015
    Sorry, I meant cut new holes for can lights in the spancrete.