Yes...anytime you put water on anything it will contribute to the deterioration....so will walking on the floor.
Linda C

Water and steam are NOT good on hardwood.
Common Hardwood Myths
3. Damp mopping is the best way to clean a wood floor.
To the contrary, water and wood do not mix. Throw away that bucket and mop! Water causes deterioration of the wood itself, as well as the finish. Use maintenance products and procedures that will not harm your urethane finish.

10. Kitchen floor cleaner with vinegar, ammonia, or abrasive cleaners are the best products to use when cleaning my floor.
    Never use these kinds of cleaners, as they can dull and damage your hardwood floors and void warranties. Use products safe for urethane finishes.

11. It is always best to use my vacuum with a rotating brush to remove grit and debris from my wood floor.
    While weekly vacuuming is important for removing dirt and grit, a special hard surface brush tool should be used.

A beater bar with a hard bristle brush can scratch your hardwood.

17. Wood floors require a lot of time and effort to maintain them.
    Unlike other types of floor coverings, hardwood floors can be kept looking like new with a minimum amount of effort. Never damp mop your floor. Use only products designed for wood floors. Just spray and dry mop across the floor.

I have heard the oil-soaps are the best way to clean my wood floor.
Soaps will leave a harmful yellow film causing the finish to alligator and crack.

Here is a link that might be useful: Read more HERE!!!!!!!!!!!!!

Shelly - I assume you mean water based polyurethane?

The company that sells my steamer (not a Shark) gives instructions for using it on hardwood. You are essentially running a hot, moist towel over the hardwood. As long as it isn't too hot or leaving puddles - the problem some people are reporting with their Sharks - I don't think it is going to damage the floor.

I don't buy into the notion that you can't damp mop a wood floor. I think that companies that tell you not to do that are targeting the kinds of people that would get the floor overly wet and then let the water soak in.

Didn't ReeRee say she uses her Shark to clean her hardwoods?

I called Gold Coast Flooring, a large distributor of all wood floors and related products to ask them their opinion. Their showroom floor is coated with Traffic, a water based poly. They said they wouldn't recommend any steam vac. The moisture can affect the would underneath the finish. So if you have been using the steam vac with no problems I see no reason to change. I am considering buying one but I am not sure I would use it on wood.
Thanks to all for your response.

Using a steam cleaner on most types of prefinished flooring will void the manufacturer’s warranty. Read the warranty information on your particular floor. On a site finished floor you will need to look at both the wood flooring product & the sealer used to determine if it adversely affects you warranty.