What wood flooring is in your boat?

Looking for real wood flooring for salon that isn't so heavy I can't open the engine service hatches by myself. The rest of the boat has 3/8" thick engineered bamboo. For those floors the typical random length planks are ok, but with the large service hatches in the salon floor I want to have all the plank lengths at least 5 ft so I don't have board end seams intersperced with the hatch seams. I found bamboo vanier SPC core flooring, but the core is so heavy that it adds 45# to the weight of each service hatch. Engineered wood core, like is in the rest of the boat would only add 20# to the hatch weight. I just can't seem to find any in uniform plank lengths. I don't want to go with the 'teak and holley' small width boards and seams look.

What flooring is in your boat?

I need to keep some of the hatches as they are the only entry to the engine room. I use the larger service hatches ocassionally as it is nicer working in the engine room with them open to the sunlight.

How thick was the mahogony? Solid boards would seem to be quite heavy. I have engineered (wood core) Bamboo though the rest of the boat, but have only found 9/16 thick in 6 foot lengths.

We had a marine synthetic flooring put in our Viking but I never liked it.

I put in a bamboo faced, synthetic core, engineered floor but I don't like it. It's heavy, dodn't like they way it cut/planed or installed. The core is terribly temperature unstable. I was on the boat yesterday, it was about 10 degrees cooler than when I installed, and the hatches had enough bow in them I could see the seams curve and hear the floor 'click' as you walk on it. I thought water was the only thing tha expands when it gets cooler. I won't be surprised if this uninstalls itself during the winter when it gets down to freezing.

I found a bamboo face, eucaliptus core floor. It is ligher than the synthetic core but is 9/16" thick which is thicker than I can use so the main hatch hinges will still open. If I can find a place that will mill the back face on pre-finished flooring I'll probably purchase that material and try again.