How to Plug a big hole?

If you just want to stop the airflow and dust, then a block of styrofoam or something similar. If you want some protection for fire along with that, then firestop bricks held in a wire frame or basket.

Try firestop pillows. Pack them in the hole and then remove them as needed. STI makes some.

Good Luck , Eric

I'm almost certain that anything that's ready-made is going to be fire rated, meaning an overkill for you if you are sure you don't need it firestopped. See if the construction workers have a piece of drywall they throw out that covers your hole. May get messy to saw the cutouts for the cables, but it will be a (semi) permanent solution. A piece of Styrofoam board, correctly sized, might do well as a temporary plug.

Styrofoam

Thanks. It probably should be firestopped since it's between floors. But the hole is open and no one has tried to stop it up. The drywall would have to lay on the floor, and I'm afraid that people standing in front of the backboard will step on it and turn it to powder - which is what I'm trying to prevent. The styrofoam might work if I could carve it out to fit the hole. Thanks.

I was thinking about when I was a kid. My dad knew this guy who used to do outside work like fences, etc. He would dig a hole and throw a bag of premixed cement - bag and all - into the hole, and drive the fence post thru it. Then he would wet the whole thing down with a couple buckets of water. Bingo, a fencepost set in concrete.

I was thinking about how to do this after I asked here, and I thought that I might be able to put some heavy polyethylene sheeting into the hole, and pour a few quarts of cement into it. Then imbed a ring of heavy wire in the cement to make a handle when it dries. ;-)

Thanks. I guess those aren't available at the local Home Depot?

Yeah, I was just reading the other followup that suggested using firestop pillows. I wonder where I could get them. Thanks.

Try your local telcom supply. Grainger, graybar, ADi Litecom, CCW Rexel, Anixter, or Hilti (makes them too I think)

Try your local telcom supply. Grainger, graybar, ADi Litecom, CCW Rexel, Anixter, or Hilti (makes them too I think)

From underneath (place something heavy over the hole from the top like a brick before-hand), stuff the hole with "Roxul" or "Rock Wool" Insulation. That is the stuff that is fire resistant made from steel slag. Pack it in dense so it is tight and held in place by friction.

Do not use Fiberglass.

Then on the top side of the hole, push the insulation down so it is about

This will seal up your drafts and fire proof it and water proof it too.----But you can still easily remove it in the future to pull more cable.

PS if you are after the fireproofing to meet code, check with your fire inspector for code compliance first.

Good luck

Joel

Thomas and Betts (and others I suppose) sell material for fireproofing such holes. It is like oatmeal and can be poured into a homemade mould (cardboard?). If you're worried about future additions, install some PVC tubing when you fill the hole. put end caps on the PVC and you'll be ready for future expansion.