This is a bit more than you asked for:
I finally got around to making a prototype roof rack. A few pictures are in my album. No water shots yet. Yea, I need to clean up the storage area :embarrased ….
With no stainless available close by, I went with wood. The primary goal was to carry an 18 ft canoe down the highway as well as on the water. Secondary benefits are many. It is low profile. Easily installed/removed. It could be made much lighter (and lower cost) with fewer boards. The 18 ft would extend over the brow so that is why the extra board over the front. It would look better if the rails stopped at the curve at the stainless rail. But I always go with function over looks. I wanted the front of the canoe to rest on the bow rail. Both for support and to clear the bimini top at the stern. As you can see. No obstruction from the cabin view with the canoe on top. It actually makes a nice sun shade over the v-birth /windshield.
Another reason for all the boards is strength. I need a place outside to nap, (I get cabin fever in about 10 minutes) sightsee at slow cruise, cast fish the shore-line or sleep another person in good weather. Here it is. One pictures shows without the deck. Another shows the 1/4 sheet decking. This detracts from the looks but allows a nice deck for sliding items over and still exposes the slates for a grab rail on the sides. The corner of the rack is much easier to grab to lift yourself up to go forward. With the cockpit cover on the CD grab rails are not accessible. This deck also makes the safari top like land rovers have in Africa. There is an air gap under the rack and it provides much needed shade in the South keeping the cabin much cooler.
Why a canoe? They are the most versatile boats made. I need to carry at a minimum: Two adults and two big dogs and a cooler. A well designed canoe can handle this plus big water with ease. They row great, are fast compared to a rowed inflatable and don’t need a kicker. Pop up a sail and they zip along on a breeze. Make them practically tip proof by adding an outrigger. If you still feel the need for a kicker they can handle that, too. The best part is I can deploy the canoe faster than you can say “Where’s the air pump”?
The canoe is designed to be carried by one person. The yoke is centered in the boat so when you pick it up it is balanced fore and aft. When you pick up an inflatable the weight always falls away from you making it difficult to maneuver. Hoisting the canoe in to the boat and up on to the roof may seem like a super human feat. But it is quite easily done by one person. The canoe in the pic is an expedition type. 18ft long, 37” wide. Made out of the heaviest most durable material (I plan to use it/scraping on coral in the Key’s) in “Royalex” it weighs about 70 lbs. The same boat made in Graphite or Kevlar weighs in at just 39 pounds. So many a light weight boat are available. If you are curious about canoes go to this website and order the free catalog.
http://www.wenonah.com/links.php
It goes into great detail about all aspects of the canoe design as well as the largest selection and design explanations of canoes I have found. More than you needed to know, right?