How to get urine smells out of hardwood floors

Ever have a cat that treats the litter box as a suggestion? Or move into a place that smelled fine until it rained for the first time after you moved in?

Bad news — urine not only smells terrible, but it’s full of bacteria and it off-gasses ammonia fumes that can harm your respiratory system.

Good news — you can get rid of it. But how?

First, we need to get into what makes it stink, and why the smell hangs around for so long.

Why is the smell of old pee so hard to get rid of?

So what makes pee smell like pee? None of the liquids you drank smelled like that.

Because urine is a carrier material for part of the body’s waste, it is almost all water with a few gross odds and ends.

What pee is made of, according to Bio Pro:

  • Water. Human urine is an aqueous solution of over 95% water. Cat urine is much more concentrated.
  • Urea. A colorless, odorless, non-toxic compound comprising ammonia and carbon. At least, it’s odorless until it breaks down.
  • Chloride. When you eat food, sodium chloride (salt) is absorbed by your intestines. Excess chloride goes out in urine.
  • Potassium. An electrolyte that aids digestion.
  • Metabolic waste compounds. Creatinine and other byproducts.
  • Uric acid. Okay, this is it — the extremely sticky, stinky component of pee that’s hard to get rid of.

It’s the breakdown of urea and uric acid that makes pee stink. Uric acid contains insoluble salts that bind it to whatever it comes into contact with. The longer it stays there, the more bacteria feed on it, releasing ammonia.

You can mop and mop with your usual floor cleaner, but unless that cleaner contains an acid, it won’t work.

Ammonia is a base, and you must fight it with acid. Most household cleaners and soaps won’t work to get rid of the smell because they don’t contain the acid necessary to break down ammonia and unbind it from the wood.

That’s where the distilled white vinegar and baking soda come in.

Before you spring for expensive enzymatic cleaners, try these dead simple DIY methods first.

3 DIY ways to get rid of old urine smells

Great news! You can do this cheaply with the same safe, natural ingredients you can make your own cleaning products with. Here’s why they work.

Baking soda is an alkali (base) that neutralizes the pH of uric acid. Fresh urine is more acid than base. So for fresh puddles, throw some baking soda on it to neutralize as much uric acid as possible before it starts to break down and bind to the material.

White vinegar’s active ingredient is acetic acid. So, how does it neutralize uric acid? It doesn’t. Uric acid breaks down into ammonia and carbon dioxide.

Baking soda is good for breaking down uric acid and sucking up gross smells, but it won’t kill bacteria feeding on the organic waste products. Vinegar will.

For fabrics, upholstery, and small areas of floor

If your pet has peed in your hamper — or worse, your laundry basket full of clean clothes — don’t worry. Just rinse the affected clothing and then soak in water with baking soda to attack the uric acid right away.

For hardwood floors

Depending on how much of your floor is affected, you may want to make enough solution to mop with. If you’ve ever moved into an apartment where the previous tenant had pets who left every room tainted with aging urine, you know you can’t depend on the landlord to have the floor cleaned properly.

Make your own vinegar and water solution to mop the floor with. Two cups of distilled white vinegar in a bucket of warm water should do the trick. And to combat the smell of vinegar, it’ll help to add the citrus oil of your choice.

If the smell is extra monstrous, or the stains are extensive and have been accumulating for a long time, expect to repeat this step.

As a last resort

You can soak old towels in hydrogen peroxide, lay them on the floors, and leave them there for a few hours. This is a last resort not just because it takes up to eight hours, but because hydrogen peroxide is a mild bleach. It might eat through the finish and lighten the wood.

Vinegar and baking soda work better solo

Vinegar is an acid and sodium bicarbonate is a base. Remember that an acid cancels out a base. If you mix them together, they’ll neutralize each other instead of the uric acid.

Commercials have brainwashed us into thinking that bubbles clean stuff. But bubbles are just pockets of air contained by a fluid membrane. Bubbles do not equal clean. Nor do they mean the solution is breaking down or neutralizing the uric acid.


You don’t necessarily need commercial or enzymatic cleaners to eradicate odors from pet stains on your hardwood floors.

Two cheap, natural ingredients you probably already have — baking soda and distilled white vinegar — might do the trick.