My mk 1 has similar shelves with a 'void' underneath, but the wall below the shelf is pretty much vertical, and has tapered into the hull before it reaches bunk height. Certainly the toe of my V berth is wider than yours looks in that pic.

The carpet looks kind of aftermarket to me too, maybe someone insulated your boat?

Steve,

I believe that's just a hull liner to provide insulation. My 1984 Mk I has it in the V-berth and also in the aft berth. I assumed that's what it was. I could be wrong :) It's also occurred to me that if it really was for insulation, then it should be filled with foam, not air, but then again, maybe it is! I haven't opened it up to see.

Agree that the carpet may have been added by a PO.

Congrats on the new boat!!!

- nick

Steve,
The void you mention is part of the hull liner. You are not losing 8" of V-berth space, as the void tapers from 4" at the level of the shelf, to 0" at the level of the base of the cushion. I assume it is for strengthening the hull, as that is quite a large expanse of hull in that area, but that is just my guess. I've heard of owners cutting into the void and creating additional storage, but it hardly seems worth the effort for the amount of storage gained, IMHO. The carpeting was definitely added by a PO. Reminds me of a 1968 Grampian 26 I used to own. I've never seen that before on a Catalina. From the pix you posted, the carpeting was added, and one shelf was added, but everything else looks stock. Hope this helps.

Tom, have you ever heard of anyone filling the void with expanding foam?

Nick,
No, I haven't. Unless you are VERY careful with the amount of foam, it would bulge out the sides of the liner, and possibly the hull. That stuff exerts a LOT of pressure. The more important question would be why go thru all the effort? Noise? Flotation? It takes a lot to offset a 6000 lb keel! :-)

I've thought about insulating that space, and trimming it out with the same 'slat' ceiling that's above the shelf, just to keep it from being so cold during those early spring/late fall nights. I always seem to roll over in my sleep and wind up with my back against the side; cold..!!:eek:

On a home improvement show, I saw mention of a 'low expansion foam' insulation. I'd think that might work without the danger's noted by Tom. Project isn't high on my priorities list, but I have thought about it; along with many other things..;)