Chris Shearer Cooper wrote:
I live in Colorado, and a few years ago had a bamboo floor installed
in my kitchen and living room, and have been very disappointed.
Despite the whole-house humidifier attached to the forced air heating
system, the "planks" (is that the right word?) contract in the winter,
,,,

So now we're wanting to replace the 20-year-old carpet in the upstairs
with some kind of wood floor, and are not sure which way to go.

,,,
...whatever we use, it needs to be prefinished.

There are some nice-looking engineered wood products, but we're
concerned about the odors ... the off-gassing from a lot of those
kinds of products gives us headaches, which pushes us towards solid
wood, but then with solid wood you can't install a floating floor, so
I'm worried we would get the gap problem again. ...

Was the guy at Home Depot right, that the more traditional woods (oak,
for example) do better in the dry climate of Colorado?
....

Fact -- wood moves. Solid wood moves more than some of the engineered,
composites less. Sounds like you would only be really pleased w/ a
solid-surface flooring instead.

As for how much, there are nominal shrinkage data at the US Forest
Product Laboratories site that you can compare and there's undoubtedly
information from the manufacturers of the various products as well.
Installation instructions will cover how much spacing to leave.

As another said, acclimation is important but it won't eliminate
movement entirely. If material solid flooring is installed extremely
tightly at the very driest condition there's a possibility it may
actually buckle during a prolonged damp spell.

But if you're expecting to never have a joint line open in a wood
flooring product you had best be thinking something else is my
recommendation.

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