My thanks to all and the great tips and ideas. This was in no way an easy task in that the move from one into another allowed less than half a day and this was taken up with a professional carpet clean. I checked in with a local supplier (Janitor's Warehouse) and picked up a product called OxySlam. A peroxide base cleaner that can be used in clothes wash as well. lov2garden's radical approach is the one we ended up getting closer to. The drapes are down and gone. We washed all surfaces especially tops of doors and frames, inside the weatherstripping, vents down and scrubbed. Windows washed, in this case, the vinyl frames can be removed, etc, etc. We have started the paint job with kils (yes - a familiar product for me) the carpets are coming out being replaced with laminate - room by room. It will take time but eventually the entire inside surface of the house will either be kils, and painted or removed. There really is no other way to be absolutely certain. I have only one other thing that I may have trouble cleaning. There is a moulded plexiglass skylight in the kitchen area that is going to need some care. I'll let you know of the outcome. Thanks also for the Canadian references. Yes, the 2010 Winter Olympics turned out great but the snow is now arriving for some of the best spring skiing ever!! Mother will do it as she sees fit - her sense of timing and humour must be seen to be appreciated. BC is immense and contains some of the freshest water and air, great surfing beaches, I could go on but -------

The enzyme cleaners did the trick for us. Took several applications but finally the odor was gone. That was carpeting in our finished basement. In another room our sick old cat had numerous accidents all in the same area. We were replacing the carpeting there anyway, so after she died the installers were there pulling out the old carpeting. You could see under the carpeting and padding that the porous plywood subfloor had been soaked in urine and reeked. I asked the installers what we could do. One young man said to pour an entire box of baking soda on to cover it and leave it on. This was a deal where they pulled out the old carpeting one day and installed the next. The next morning before installation we swept up the baking soda and you could already tell a huge difference. Then we laid down another flatter layer of baking sods on the same spot and the padding and carpeting was installed right over it. Thhis really worked. I have always been grateful to him for solving the problem. He said he had done this numerous times. So if you can fence off the affected area of the floor so no one tracks through it, I would try this. You might need to try both approaches.

Rewash using normal detergent. 1st rinse: use 3/4 cup Baking Soda and 1/2 cup of Vinegar. 2nd rinse: use your favorite fabric softener. Lestoil scent will be reduced or close to no scent.

Even better than Nature's Miracle is Kennel Odor Eliminator by Thornell http://www.amazon.com/Thornell-Kennel-Odor-Eliminator-Gallon/dp/B0002XI7DW My old house POs had cats, lots of them. And no litter box. It's more expensive, but it did in 4 treatments what Nature's Miracle (and others) could not. Now, the one problem you may have (and I did) is that the urine has infiltrated the HW and is into the subfloor. Try TOE first, but if it still smells....then your only option left is to remove the HWF and treat the subfloor. Mine was so bad I removed the entire subfloor because it had sunk into the joists below, but I think I'm a worst case scenario. Good luck. PS....the smell is due to the ammonia salts left behind, which are activated by moisture, hence the stronger smell when the humidity rises. My floor was so bad it changed color (got darker) when it was humid...hopefully yours is not!