Hi Rick,

How about buiding something like a Mill Creek or a Birder type boat. You could modify the deck if you wanted, by making the cockpit a bit shorter and the side decks a bit wider. You could strip build a deck for it, like some folks here have done. Don't forget to make some good sized, airtight chambers fore and aft, or stuff in plenty of float bags.
The Mill Creeks/Birders are wider and would be more forgiving of a "curious" passenger, and since thaey are beamier, they have great capacity without the need for excessive length.
If you opt to strip the deck, you could use temporary deck beams along the length of the hull, strip the deck right on the hull, then glass the outside, pop off the deck, clean up and glass the inside, remove the deck beams from the hull and install the deck like you would on a stripper. I think this has been mentioned here before.

Or, you can use permanent deck beams, gluing the deck material directly to the beams, glassing outside only, and epoxy sealing the underside of the deck. The beams along the cockpit may need to be more like gussetts, since they will be cut through when cutting out the cockpit opening. Comings could be built like Nick's or like the standard Mill Creek comings. The weight of the deck beams will add up, so the boat may be heavy if done that way, I dunno????
garland

: Does anybody have any ideas on designing a deck for a stich and glue kayak
: that can accomodate me and my 80lb dog. Im trying to stay away from a 20
: ft double and simply redisign something that already exists.