Bubble sides are a sort of tumblehome too. Tumblehome is a generic term where the rail width is less than the max waterline width. The hull is flared until about four inches below the rail, then there is an edge and a sharp tuck into the rails. There are others but I think they are all DY designs. He told me it is not technically tumblehome because it flares out at the gunnel. I'm not sure of the technical term but Dave Curtis called it 'bubble sides'.

I imagine this fact is reflected in the cost. Like I mentioned, I read somewhere i that it creates a much more complicated job to make this feature. but the Lake Placid boats, the Colton and the Swift and the defunct ( sadly as this is MY favorite canoe) are of his design and all have this feature. Yost seems to be a fan of it, not sure if it is his original design. The shape is similar to the sponsons on the old wood canvas old Town Canoes, they were designed for flotation, ( I have one I am restoring some day!) these have the same effect as fluting in knights armor, the crease put into the metal that makes the same panel of metal much stronger then a flat plate. With this bulge, there is no creaking at all in the two Bells, one with the black gold carbon layer and the other, the stripped down lightest weight model, I have paddled. this feature- not sure what the name of it is, is within 5' from the top of the gunnel. It is so stiff and brittle that seems normal. I assume the bulge you are talking about is the tumblehome? I have a kevlar boat with a lot of tumblehome and it still creaks and cracks around.

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