We are building a log cabin in Western Maryland and are receiving conflicting information on which type of flooring to us. Our home will be vacant more than it will be occupied and we don't expect to keep the heat or air conditioning running to provide a constant 75 degree temperature. Summers temps will probably range from mid 70s to low 80s; wintertime could get into the low 60s. The flooring will be laid on top of advantek plywood. Under these circumstances, engineered or solid and why? Thanks!

Of the two, your going to have better "luck" with engineered.

Your house is going to have what is called "the greenhouse effect", which is not a good thing for wood.

In your circumstances, a wise choice would be to select a wood species that is inheritly stable. Engineered wood floors of today are extremely well made (at least the good ones). Seems to me, with a log cabin, a pine or fir floor would be more in keeping with the rustic appearence. There are some reclaimed antique heart pine floors that are nearly as hard as red oak and look great. There are also engineered pine floors that are of the floating style. Some very stable wood species are antique heart pine, true teak (not S. American), mesquite, and flooring that is quarter sawn. Floorguy is correct that you may experience the "green house effect" if you go away and do not provide any air transfer in your home. Just having your central fan turn on a few hours a day with no heat or ac will help tp dissipate vapor from building up inside the home.

Vacation home? Vacation home usually means "improper acclimation" after installation. Who wants to pay high energy bills on a vacation home?
Wood requires acclimation of materials and building before and after installation. Inadequate acclimation results in cupping or excessive gapping.
Engineered flooring would withstand these conditions better than solids.