Fire pit on concrete?

[KevMel]

I am interested in putting my 48” round cast iron fire pit on my concrete pool deck, but I understand the heat will ruin the concrete.  The fire pit sits on a stand that raises it off the ground about six inches.  Does anyone have recommendations on how I can prevent my deck from getting damaged?  I’ve seen inexpensive heat shields that appear to be fabric and one by a company named Deck Protect that’s a bit pricey (>$300).  Are there any DIY options?  THANKS!

[cams2705]

Get yourself four 24" concrete paver bricks like THESE. to put under the fire pit.

I had a friend burn a hole in his deck (duh!) and after I helped him repair the three deck boards, I suggested the same and he's been good ever since.

[Stwood_]

Yes. Block it up off the concrete pad. I'd recommend 12"

[KevMel]

Thanks, guys!  Do you think concrete pavers are fine or should I build it with fire brick?

[Stwood_]

Pavers or 8x16 wall/foundation blocks will be fine.

[KevMel]

Pavers or 8x16 wall/foundation blocks will be fine.

Thank you!

[Turner52]

Yes it will damage it. You might be surprised what will happen. I know I was. I was changing some copper piping around in the basement. Almost ready to solder so I lit the torch and set it on the concrete floor. While assembling the last of the copper I accidently knocked over the torch. No big deal it was on conrete. About a minute later it sounded lke a rifle going off. Scared the @%%& out of me. An area about the size of a half dollar had blown out of the concrete. Maybe a 1/4" deep. Concrete is never totally dry. The torch caused moisture in the concrete to turn to steam. The concrete was about 2 years old.

[FS7]

I use a movable cart. I built it originally for use on a composite deck, but now it sits on a wood deck. For what it's worth, I have never seen any problems using a fire pit on a wood deck, concrete pad, or asphalt driveway. Just on plastic. Yes, it gets hot, but not that hot. Enough to warp plastic, not enough to blow up concrete. Though this thread makes it seems somewhat common.

What I did was take a piece of concrete backer board, build a "frame" under it with PT lumber, tile the top (to avoid cutting tile, I sized the whole thing to the tile), and then edged it with PVC trim. There are heavy-duty casters attached to the frame so it rolls around easily and stainless steel handles to push or pull it. If I could do it over I'd go with wood instead of the PVC, since embers will just melt the PVC. It not only makes the fire pit easily movable, it also protects the surface from the heat.

[fixtureman]

You shouldn't need to raise it up to high as heat goes up and there will be air flow under it