Often, prior to resanding of hardwood floors, our crews will assess the condition. They often discover pet stains in many areas of the room.
Urine is made of 91-96% water, as well as an assortment of inorganic salts and organic compounds, such as proteins, hormones and a wide range of metabolites. Urine excreted by cats and dogs is similar in make up, and will cause the same kind of damage, should it come into sustained contact with the wood fibres of the floor. As it soaks into the fibres, it will darken the stain of the wood.
In the past, when floor restorations were not done by professionals, and floors were still treated with waxes, a strong solution of 40% peroxide was used to remove the stains, after the waxes were removed. This “bleaching” technique would work over an extended period of time. The treatment methods for restoring hardwood floors have changed, so have the formulas that are used to coat the floor.
Usually, when the floor is being resanded, the urine stain will not appear until the varnish is applied. This is because the urine stain has soaked into the floor, through the gaps or cracks, down into the tongues and grooves and beyond. The patches of discolouration will occur, as a result of a chemical reaction of the varnish with the organic compounds still in the wood. This could become costly and disruptive, as the floor will have to be resanded again.
The best option is to remove the stained hardwood floor and replace it with a new one, especially if the pet is still in the home. It will be drawn to the smells trapped not only in the floor boards, but often in the sub-floor, as well as the joists. Complete removal of the floor will determine the extent of the damage and eliminate the source of the scent that might prompt the pet to return to that spot.
Depending on the extent of the damage to the floor, the repair could be done locally, by removing a section of the discoloured floor boards, and inserting new ones. The entire floor is then sanded down, coloured and varnished.