Empty concrete bags to fill empty cores. Tools, Tips and Techniques Discuss Empty concrete bags to fill empty cores. in the Pizza Oven Design and Installation forums; I can perfectly conceptualize the idea of filling the empty cores with the concrete bags from earlier in the project. ...

[kebwi]

I can perfectly conceptualize the idea of filling the empty cores with the concrete bags from earlier in the project. My only question is this:

In the weeks since I started collecting empty bags (from my foundation and from filling the cores), many of the bags have become pretty damp (rained on, etc.). If I stuff damp or wet paper bags into the cores and then seal the top (with the hearth) the moisture won't have anywhere to escape to. Will it just turn into a mildew infested bog?

I'm in Seattle mind you.

Is there no problem with leaving wet bags in the empty cores? I guess this is a needlessly specific question, but I'm trying to figure out what to do this evening in final prep for pouring the hearth this weekend, so if I need to find a completely different solution to blocking the empty cores, I need to find it fast.

I might try to fashion cardboard table-tops, but I'm not sure if they'll just sink through.

[cynon767]

Well, to my thinking, even if they were dry, they would get somewhat damp from the wet concrete being poured on top of them. Plus, concrete is porous and will allow for some transpiration of water anyway. I wouldn't worry too much about it unless they are really wet or they are already showing signs of mold or mildew.

If you're really worried about it, you could use rubble or dirt or something; You could also be selective about the bags you use and only use dry ones. If you don't compress the bag too much before putting it in the hole and only push it down a couple inches below the top of the block, it will still hold concrete without the cavity being completely stuffed full. How many bags do you have total? How many wet, how many dry? Can you dry them out for a day or so indoors somewhere?

[kebwi]

Maybe I'll put them in the drier and catch the house on fire. I'll think about it, it isn't worth too much headache I suppose. Maybe if I put a space heater in the basement they'll dry out a little.

I probably shouldn't go to too much trouble to clean up what is otherwise unambiguously trash. HA!

Thanks though.

[dmun]

A word of wisdom from someone at the end of the project: It's extremely difficult and expensive to get rid of scrap concrete, brick ends, and other masonry trash. If you have anything like that you aren't planning on using, dump it in those holes.

[cynon767]

Originally Posted by dmun

A word of wisdom from someone at the end of the project: It's extremely difficult and expensive to get rid of scrap concrete, brick ends, and other masonry trash. If you have anything like that you aren't planning on using, dump it in those holes.

yes. this. they are the perfect little disposal area. think of it as a time capsule for rubble.

[mfiore]

I agree with dmun. Great advice. My oven has a walled enclosure. It has tons of rubble sealed inside. It also decreases the amount of loose fill insulation that I needed.

I still have a pile of hardened concrete and chunks of stone and brick. I've been slowly disposing of it. I feel like the guy in the "Shawshank Redemption", disposing of a few rocks each time.

[ThisOldGarageNJ]

I had a large area under the oven slab I used as a Time Capsule as well... Mine Included, poorly cut bricks, dirt, block, chunks of cement, and lastly a few pictures and some 2009 coins and a twinkie, sealed in a plastic bag.. If some poor SOB ever has to tear this thing down in 50 years at least he will know who he is mad at and he will have a snack... I figured since twinkies are mostly chemical it might last in there...
Cheers
Mark