I bought an old house “as is” with nasty dog peed on wood floors. Has anyone had any luck salvaging old wood floors that are stained with dog pee and smell like dogs? I’m just trying to do a cheap rehab and want to rent it out soon. And want the dog smell out of this place. It’ smells terrible!

I misread your post title and was extremely curious why you wanted to save the dog's pee!  Glad it's the wood you're rescuing.  Try this:  (Source:  ervicemasterclean.com/blog/how-to-get-dog-or-cat-urine-smell-out-of-hardwood-floors)

How to Get Dog or Cat Urine Smell out of Hardwood Floors ...

Pour the hydrogen peroxide over the stain and then cover it with a clean cloth soaked in hydrogen peroxide. Cover the cloth with plastic wrap, weighting it with a book if necessary. Allow this to sit overnight or for at least 8 hours. The hydrogen peroxide should remove any stains and eliminate the urine odor.

It may be possible but will be difficult. Dog pee is not as bad as cat urine but they're both trouble. What's under the hardwood? subfloor? concrete?

@John Morgan

Peroxide won’t work as well as you may need I bet. I’ve revived a handful of these, dog pee is better than cats by a long shot. Buy a neutralizer, spread it around heavy, poly film it, come back in 24 hours, ozonate if there is still smell (likely for a couple days or more depending on smell and ozone capacity of machine), then you’re probably sanding and throwing down whatever stain /polyurethane you desire. Expect some stank when you sand. And depending on colour expect to still have some “character” in the wood. Have a flooring guy come assess if there’s room to sand as it may have been refinished multiple times already. If you see nail heads in the long edge grooves you’re likely out of luck.

You can try and use this to remove it

https://www.walmart.com/ip/Urine-Gone-Pet-People-Stain-Odor-Eliminator-24-Fl-Oz/24706407

@John Teachout

Sub floor. It’s pier and beam. I was hoping there was an economical way to save the floors and just have them sanded down then stained. But wasn’t sure if all the dog pee over the years ruined the floors.

My floor refinisher guy can look at it and tell. A lot of times even if you can get the smell out it will leave permanent dark spots so you'll need to use a dark stain instead of natural wood.

Originally posted by @John Morgan :

@John Teachout

Sub floor. It’s pier and beam. I was hoping there was an economical way to save the floors and just have them sanded down then stained. But wasn’t sure if all the dog pee over the years ruined the floors.

I've got you, John. Here we go.

There are three ways to work on pet urine dark spots on a wood floor after you sand it, wood bleach kits, oxalic acid, and peroxide. The most popular wood flooring far and away is oak, and that's bad news for you, because oak is the least forgiving to work with. Dog urine isn't as bad as cat urine, so it isn't all bad news.

Typically on oak flooring, the wood bleach kits (the most popular one is made by Zinsser) will lighten up the spot too much and look artificial. The oxalic acid (and get the 100% stuff on Amazon, not Bar Keeper's Friend) will get it just about right. Typically peroxide guys swear by hair bleach cream developer, because it can really do a range of lightening well, but it take times to develop skill in that.

After you lighten up the spot, you're going to have to seal and poly the wood. This will go easier with water-based than with oil-based poly. With water-based poly, you put on a coat of the stuff, and usually you're fine. With oil-based poly, typically application is to begin by adding a THINNED coat of the poly as a sealer, usually diluted 50/50 with mineral spirits.

Sadly, this will screw you very quickly, as the mineral spirits in the sealer coat will penetrate the wood deeply and bring out the spot yet again.

 So what you need to do is break out a spray can of clear shellac. This takes a long time to do right, but with practice, you can add 2-3 very thin coats of shellac over the spot without causing the treated wood to re-darken. After you get the spot and a 1-inch perimeter around it coated with the shellac, you can cover the whole thing with oil-based poly.

It takes a lot of practice to get this right, and it can get frustrating. But if you have the time to invest learning this trick well, you can bring back a lot of floors. A lot of flooring guys hate this because its a timeater. But sometimes they can fix a spot on the first shot, which makes them look good. If you plan to continue working in houses like this, yes, it's worth developing this skill.

Look online for how to use oxalic acid and peroxide cream developer to lighten floors, the actual technique you'll use. But a Zinsser wood bleach kit and follow the directions.

Sometimes, you're going to want the whole wood floor to be darker, and anytime you do, that's great news for spot treatment, because it makes matching the stained wood to the rest of the floor a lot easier. But other than giving oak the amber tint that tough, oil-based poly imparts, I've always been a fan of keeping old floors as light as possible when refinishing. Historically, of course, dark-stained flooring was less a fashionable possibility and more a solution used to hide multiple imperfections in cheap oak floors. When faced with an ugly situation where there are spots all over the place, however, it makes more sense to do a darker stain over the whole oak floor and make your life easier.

Originally posted by @Jim K. :

Originally posted by @John Morgan:

@John Teachout

Sub floor. It’s pier and beam. I was hoping there was an economical way to save the floors and just have them sanded down then stained. But wasn’t sure if all the dog pee over the years ruined the floors.

I've got you, John. Here we go.

There are three ways to work on pet urine dark spots on a wood floor after you sand it, wood bleach kits, oxalic acid, and peroxide. The most popular wood flooring far and away is oak, and that's bad news for you, because oak is the least forgiving to work with. Dog urine isn't as bad as cat urine, so it isn't all bad news.

Typically on oak flooring, the wood bleach kits (the most popular one is made by Zinsser) will lighten up the spot too much and look artificial. The oxalic acid (and get the 100% stuff on Amazon, not Bar Keeper's Friend) will get it just about right. Typically peroxide guys swear by hair bleach cream developer, because it can really do a range of lightening well, but it take times to develop skill in that.

After you lighten up the spot, you're going to have to seal and poly the wood. This will go easier with water-based than with oil-based poly. With water-based poly, you put on a coat of the stuff, and usually you're fine. With oil-based poly, typically application is to begin by adding a THINNED coat of the poly as a sealer, usually diluted 50/50 with mineral spirits.

Sadly, this will screw you very quickly, as the mineral spirits in the sealer coat will penetrate the wood deeply and bring out the spot yet again.

 So what you need to do is break out a spray can of clear shellac. This takes a long time to do right, but with practice, you can add 2-3 very thin coats of shellac over the spot without causing the treated wood to re-darken. After you get the spot and a 1-inch perimeter around it coated with the shellac, you can cover the whole thing with oil-based poly.

It takes a lot of practice to get this right, and it can get frustrating. But if you have the time to invest learning this trick well, you can bring back a lot of floors. A lot of flooring guys hate this because its a timeater. But sometimes they can fix a spot on the first shot, which makes them look good. If you plan to continue working in houses like this, yes, it's worth developing this skill.

Look online for how to use oxalic acid and peroxide cream developer to lighten floors, the actual technique you'll use. But a Zinsser wood bleach kit and follow the directions.

Sometimes, you're going to want the whole wood floor to be darker, and anytime you do, that's great news for spot treatment, because it makes matching the stained wood to the rest of the floor a lot easier. But other than giving oak the amber tint that tough, oil-based poly imparts, I've always been a fan of keeping old floors as light as possible when refinishing. Historically, of course, dark-stained flooring was less a fashionable possibility and more a solution used to hide multiple imperfections in cheap oak floors. When faced with an ugly situation where there are spots all over the place, however, it makes more sense to do a darker stain over the whole oak floor and make your life easier.

Thanks Jim! This is great info.  

@John Morgan you could also paint with odor blocking primer and float laminate over it. Might cost about the same as hiring a refinisher if you use .79 cent laminate...like the lakeshore stuff at Home Depot.

Originally posted by @Marian Smith :

@John Morgan you could also paint with odor blocking primer and float laminate over it. Might cost about the same as hiring a refinisher if you use .79 cent laminate...like the lakeshore stuff at Home Depot.

Great idea, thanks!

The prob with putting cheap laminate over hardwood for the same cost is that you’re left with a fad less durable product and will be doing it again in a few years. Do it once.

@John Morgan I had a really bad rehab that had the same issue and just rolled the dice and had the hardwood sanded/refinished and it worked like a charm. I will say the odor was pretty strong too. Never had issues afterwards and I rented it out for a few years before selling. 

@Adam Odom

That’s good to know. And I love the look of wood floors. I’ll have to get an estimate to compare. 

@John Morgan one word odorxit. Remodeled a house before that had several animals as pets in the house (dogs and cats both) the animals were not let outside to use the bathroom (from what it looked like ever) we sanded down the hardwood filled a pump up sprayer with the odorxit (super contracted stuff mix as stated in bottle) sprayed all of the floors till they were soaked with it then opened the windows to let it all air dry. After it dried we proceeded as normal. No problems and looks great!

@Calvin H Duggin *concentrated

There is a great discussion about ozone devices in another thread, it convinced me to buy one. 

We have had success with cleaning floor, baseboard, casings and trim with TSP, and then applying Kilz Oil Based. This will seal the floors. 

Natural Finish - after removing stains chemically or mechanically, mix 1 part Tung Oil, 1 Part Mineral Spirits. Apply 4-5 coats with a paint roller. That will fill in wood pores and create a shell on top. This seals all odors. 

Originally posted by @Marian Smith :

@John Morgan you could also paint with odor blocking primer and float laminate over it. Might cost about the same as hiring a refinisher if you use .79 cent laminate...like the lakeshore stuff at Home Depot.

 ^^ this is what I would do. You could spend days trying to recover this floor and it may never be right. Guaranteed the odor blocking primer will take care of it and you can lay a nice (new) laminate over the top that is guaranteed to look right and be done quickly. Worst case you try other suggestions and fall back to this.

@John D.

John, I’ve used both Kilz original oil based (on any surfaces that are real bad/ deteriorating) and then their newer product that is water based called Restorer... most recently (April) I bought a place that had two beautiful dogs that literally never saw the outdoors and after stripping the carpet rolled Restorer on the entire subfloor before throwing down the usual LVP. I was really impressed. Had to do a few bedroom walls... actually all 7 with it as well. Really great product and so much over than working with oil.

Now the cabinets I refinished,... they got oil primer.

Sorry, it’s called Restoration not restorer

I like the dark stain idea. Sand it down, oxidize it per @Jim K. 's instructions, stain it dark then poly the heck out of it. Poly will lock in that aroma. Just make sure it isn't in the drywall too.

@John Morgan

I wouldn't save the old dog. He shouldn't have peed on the floor.

Originally posted by @Kris H. :

Sorry, it’s called Restoration not restorer

FYI, Kris, I had a conversation with them recently. Kilz Restoration is rebranded Kilz Max, Kilx Oil-Based Indoor/Outdoor is rebranded Kilz Complete.

@John Morgan Hello, I know lemograss works well on the smell, and baking soda neutralizes it.

@Kris H. Do it again in a few years? Maybe but I have two 9 year old 99 cent laminate floors and one 7 year old .99 floor in pet friendly houses and my son and three other guys, a dog and a cat live in a house with 5 year old laminate over old hardwoods in a pier/beam and its 5 year old floor looks great even in the kitchen. It is a very pretty floor. The 10 year old I have only noticed the kitchens and they look fine and the 7 year old had a dishwasher leak. The floor peaked and flattened back out but it is noticeable if you look close...not if you don’t. The 5year old floor was 50 cents on clearance and we went ahead and put it in the bathroom over original tile and it is peaked in front of the tub but even there it doesn’t look too bad. We had some rubber underlayment we used so not too worried about water getting under yet but will likely replace with vinyl planks sometime as it is a wood subfloor vs slab. Big fan of well made low priced laminate, but last two houses got vinyl planks.