When I did my garage addition in 2020, I used these little plastic chairs. Pretty easy addition, cheap, and I know the rebar isn't laying on the bottom or 1/4" from the top. They are currently .29 each. Not sure what they were 4 years ago.
EDIT: They were .17 each in 2020.
Nice thing about Menards... they keep your receipts on-line for quite a while.
The 2-1/4in plastic rebar chair is a durable plastic rebar support system that is ideal for concrete applications. The chair is designed so that the rebar snaps securely into place allowing the rebar to sit above the ground while concrete is poured. The chairs are easy to work with and...
www.menards.com
(click to enlarge).
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