Do my floors have pet damage, or water damage?

by | Aug 31, 2022 | Refinish hardwood floors, Wood floor damage, Wood floor refinishing, Wood floor water damage

“Can you tell me if this will sand out?”

Some customers come to us unsure of whether their floors can be saved. But about 25% of them arrive with panic in their hearts and photos like the ones above, hoping that we have a magic cure.

Most water stains sand out; most pet stains don’t.

Pictures like this make our hearts sink too because pet stains are the only true deal-breaker for hardwood floors. I know they sell flooring bleach  and other concoctions that claim to remove stains from floors. But dark grey and black stains that come from corrosive effect of decomposing urine usually don’t respond to bleaches and peroxides.

We don’t want to take away all hope, but we want you to be realistic in your expectations.

If we thought there was a product to fix pet stains, I guarantee that we would sell it. But as much as we want to sell you stuff, we refuse to make money on products that don’t work. So, this gallery isn’t going to tell you what to do with your pet stains, it’s going to help you decide if you still want to sand your floors if you have stains that can only truly be fixed by removing and replacing the damaged wood. Better to know the truth up front.

But some really ugly floor stains aren’t from pets, and many of those have a greater chance of removal by sanding. Mind you, we’re not promising they can be easily removed by sanding; you may have many hours of 36-grit grinding ahead of you to find the undamaged wood behind your stain.

But there is hope.

Do you need advice for your specific hardwood floor problem?

Get a one-on-one phone consultation with a hardwood flooring expert. For a small fee of $25, we can provide the wisdom and knowledge that you need to complete your hardwood flooring project. When you don’t know what you need to do next, that’s when it’s time to call Pete’s Hardwood Floors Help Hotline.

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Is it pet or water damage?

Pet stain

This is a classic pet stain. Urine soaked into carpet, carpet pad keeps the liquid from drying, so it quickly decomposes into ammonia. The decomposing material is kept in constant contact with the wood surface by the carpet, so it continues to burn and discolor the wood.

These marks can go deep – even beyond the top of the tongue of each board, which is as far as you can sand. Stains like these will not sand out, will not bleach out, will not even be camouflaged by a dark pigmented stain.

Water Stain

This could be mistaken for a pet stain, but it’s clear from the shape that this is from a catastrophic, one-time flood of water that flowed out of the kitchen and into the living room.

And while the black color is usually the tell-tale sign of pet-urine burn, in this case water from an overflowing dishwasher carried enough dissolved metal to react with the tannins in the adjacent oak floor to create some black staining.

This damage is likely to be much shallower than typical pet damage and will eventually sand out.

Pet stain, before a Pete’s customer

Looks like a nasty pet stain, and we gave these DIYers little hope. But we have learned never to underestimate the perseverance of our customers. Check out the next picture for their “after.”

The same pet stain, almost completely sanded out by a Pete’s customer

This couple were determined to fix this floor. The text I received from them mid-sand said, “We gave up at midnight last night. We spent 12 hours on this room alone.” But they did it.

Water stain

You can see the culprit in the top of the photo: the dreaded over-watered pot plant. Also commonly seen where you placed your Christmas tree.

These spots will take some extra sanding, but they do usually sand out. But remember, this is assuming you are sanding the entire surrounding floor to bare. You can’t just sand this spot and coat it and hope that it will blend back into your existing floor.

Water damage

This one is deceiving. It has that dark grey appearance of a pet stain, but this was actually caused by years of wear and tear and foot traffic, wearing off the protective finish and slowly replacing it with dirty, water-damaged driftwood. This will sand out.

Here are more pet-or-water images that may help: