BetaB4 wrote:
....
So, any thoughts on whether it's okay to use plywood for more strength or
would I be better off using particle board?

More than "ok", it's the only logical choice. CD is fine despite what
somebody else says it's stronger than the alternatives given unless go
w/ _extremely_ expensive which is simply stupid for a laminate counter base.

Normally countertop construction is simply single layer w/ a narrow
piece around the outer edge to give the illusion of the extra thickness.

In this case as an overhang the full double-ply would be _a_good_thing_
(tm). As somebody else said, some yellow glue and screw it together to
serve as a clamping action "while the glue dries" and it'll be plenty
strong enough.

It wouldn't hurt to have a single support on the 16" end in the middle
perhaps but it really wouldn't be mandatory--1-1/2" ply will support a
sizable load and laminate is quite flexible to just a little bending.

But, as it is a rental and subject therefore to more abuse than normal,
a stiffener as also suggested would be cheap insurance.

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