I'm installing some new kitchen worktop and a new sink in the kitchen.

(bit annoying really as the kitchen is pretty knackered but replacement
isn't gonna happen soon, and the old sink was rusting away, the tap was
knackered and the work top swelling cos of water penetration)

Obviously I'm sealing around the sink opening with silicon sealant.

Is it worth sealing the underneath of the worktop that has the
dishwasher underneath with something. PU varnish?
--
Chris French