We are getting ready to put down a floating floor in the dining room and entryway. And we knew we had a pet urine problem in the dining room. I'm replacing the underlayment, but after I got that up the problem is now urine is in the plywood as well. I have a fan on it for a few hours and then I sanded it a little bit with an orbital hand sander. The stain is going away but the smell is still there. The urine didn't soak all the way through because there is no stain that I can see from the crawl space. I'm thinking the only other thing I can do is maybe some hydrogen peroxide on the plywood to remove the odor? and then a coat of Zinsser B-I-N or Kilz Original on the dried stain afterwards to seal the odor? Is this a good idea or will I ruin my plywood?

Thanks!
-Jason

Sanding will not help. Bleaching won't either and may harm the plywood a little. Try looking into this:
http://www.urine-off.com/default.aspx

Never bleach urine, unless you have open windows and a pusher fan and a puller fan in those windows. Your going to make one toxic cocktail, by doing so.

i've hit many a bathroom subfloors with kilz after removing carpet. its yielded the best results ive found yet without replacing it

I have used Kilz before with good results. Only use the oil base over plywood. Read the label, one type of Kilz says it is used for this purpose. I think the can was white with green lettering, but I am not positive about that. Two applications are better.

Thanks guys I picked up a spray can of Kilz Odorless and will give that a try tonight!

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