Should I use a release agent on my wooden concrete forms?

Does anybody use a release agent to the forms for the base slab and the hearth forms? If so does it have an affect on the top of the hearth “sticking” bricks to it?

Thanks ahead

Darren,
Didn’t use anything and the forms poped right off. The styrofoam did leave tiny beads that needed a wire brush to remove.

Believe it or not I used peanut oil. Just for a peace of mind. Most likely din’t even need to do that.

Welcome to the community, Darren!

A release agent is really not necessary. The wood contains the concrete but does not adhere to it.

That would be good if you wanted an absolutely pristine surface, but you could also skip that because your void is filled with a mix of portland cement and an insulating material like Perlite or Vermiculite. You might want to remove any big hunks that were left behind, but the fragments won’t bother anything.

Good luck with your build!

Thanks for the replies. In the long run everything went well.

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