Concrete – Do I need to add a cardboard barrier around drain pipe before adding concrete

concrete

When I removed the concrete to add an extension on the drain, there was cardboard wrapped around the drain pipe. Before I add new concrete, do I need to wrap the pipe with a barrier (or card) again – and what is the purpose of this?

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Best Answer

I have used cardboard and styrofoam around pipes this helps in several ways and I would recommend at a minimum some heavy paper stock or cardboard and grease to allow for movement in desert or high temp zones. Just guessing based on the photo. No high water issues it is best to allow movement.