What are the advantages of using structural composite lumber rather than solid lumber?

Advantages of using structural composite lumber include its highly stable material, in that it's much less likely to warp or split, its ability to sustain heavier loads, and its wide range of different physical applications. Solid lumber does not hold any of these properties, and generally is more likely to fail.

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant.