Subscribe or Renew Membership Subscribe Renew

Thin concrete countertop

Gene_Davis_'s picture

My friend wants to do his countertop by casting, in place, 7/8" thickness of concrete over an exterior 3/4" plywood underlayment. Does anyone have experience with this? The articles I see talk of tops made at 1 1/2" thickness and reinforced so as to be self-supporting, that is, they are laid directly on the cabinet bases and not on an underlayment.

(post #89061, reply #1 of 5)

If it were to be that thin I would put a felt paper down first to minimize cracking from the ply movement. then lay it up like a stuco wall with the expanded metal. On the other hand I would not want to make a counter top that thin from concrete. What have you to loose but a counter top.

(post #89061, reply #2 of 5)

A concrete mix strong enough to make the surface of the counter top wear resistant will shrink and crack for sure.
7/8" is far too thin -- it just might work at that thickness/thinness with pre-stressing but that's not cost-effective for a one-off counter top, nor a job for someone who is unfamiliar with the process.

I'd suggest doing away with the ply and casting the top at 1 5/8" thick with expanded metal re-inforcement, in a mould.

(post #89061, reply #3 of 5)

Look up the piece on concrete countertops published in FHB in late 2000, I think.

(post #89061, reply #4 of 5)

Wait up guys, 'nother concrete countertop article on its way to you in about 2 and 1/2 months, plus a book on the topic by the best in the business, Fu Tung Cheng.


(post #89061, reply #5 of 5)

Hey Andy, can you put me on pre-order for that book?