You are not the first to come here with this whizz-bank idea. Within the last two months a gentleman with the same questions posted here. He said,"I got a foam mold,a mile of Kevlar at a cheap price and a bucket of polyester resin. How do I make kayak"? He could not be dissuaded. We have not heard from him in along time.
Here are some obvius questions to ponder before you travel down this perilous road.
Who built the mold? Was it built to a proven design?
How old is the design? Have you paddled a boat that came off this mold?
Have you worked with polyester resin before? Are you aware that in spite of it's cheap price it is not popular among us amateur boatbuilders because the vapors make it dangerous to use inside a dwelling? Have you ever had a case of "fiberglass itch"? I have. Sorry I got off topic.
In regard to your question; 4 8oz. layers on bottom and 3 on top. Forget the mat. It'll make your boat so heavy you'll get a hernia trying to drag it up on the beach.
Has the guy molding the all-Kevlar kayak sent a progress report yet?
Charlie

: I have a mold for a 18 ft kayak and I'm looking for imformation on the cloths
: and fiberglass mats that are the best to use to make a light and strong
: hull with polyester resins. The number of laminations of material needed
: with out using carbon or kevler.