It’s borderline unforgivable to the snobs on House Hunters and a pollen-clogged nightmare in spring. Its absorbent fibers are also no match for even the most basic spills and moisture. Sure, carpet is easily dirtied and often unsanitary, but can carpet make a house smell awful?

Here’s the TL;DR:

Carpet can make a whole house smell because most carpet fibers trap and absorb bad odors and moisture. These spilled liquids and moisture soak through the fibers to the padding beneath, allowing bacteria, mold, and mildew growth. An unclean carpet can make a house smell stale, musty, or unpleasant.

Now, supposedly, carpet was set to make its big comeback in 2023, according to Homes & Gardens. But before you ditch the vinyl for the coziness of carpet, consider the stink factor! Below, I’ll reveal why carpeting can make an entire house smell and how to de-stink it.

Why + How Carpet Can Make a Whole House Stink

If your house appears perfectly clean yet smells unusually stale or “off,” your home’s carpet may be to blame. The reasons for this generally boil down to the anatomy of modern carpeting.

Carpets Are Notorious for Trapping Bad Odors + Spills

Synthetic carpets first graced the public eye back in 1947. The introduction of nylon forever changed the carpet industry. Polyester and polypropylene followed not long after.

Industry experts now predict that some 90–97% of all modern-day carpets contain synthetic fibers. The core three synthetic carpet fibers are nylon, polyester, and polypropylene. 

One of these fiber types, nylon, accounts for roughly 65%+ of U.S. carpet sales in the modern era. Nylon is also hydrophilic—the opposite of hydrophobic and why nylon carpet fibers soak up spills and moisture easily.

Polyester and polypropylene are hydrophobic and repel water extremely well naturally.

Nylon carpet can absorb as much as 5–8% of its weight in moisture (i.e., water, humidity, spilled juice, red wine, etc.). Though, nylon fibers that undergo stain treatment can repel water-based spills and stains to some degree.

If you maintain your nylon carpet and immediately clean up spills, you likely won’t notice any house-wide smells linked to flooring. However, if you don’t, your carpet’s fibers could eventually begin to absorb odors, spills, and moisture. 

Nylon fibers will hold onto forgotten spills if not blotted dry soon after they happen. Unfortunately, these fibers will also latch onto seemingly long-gone odors, especially in areas with a lack of airflow.

So if your house has a not-so-great stench that smells like any of the following, the problem may lie in your carpet’s fibers:

  • Stale or musty (humidity)
  • Cigarette smoke
  • Cooking odors
  • Pet odors (urine, feces, vomit)

Check out the infographic below to learn about 24 of the more common causes of carpet stains. These could also lead to funky odors if left unblotted or uncleaned:

common causes of carpet stains (infographic)

Moisture Can Become Trapped Underneath the Carpet

Unfortunately, the problem can go much deeper (literally) than your carpet’s fibers. Just beneath your home’s carpet is a soft layer of padding known as the underlay. 

This 6–12mm layer of padding absorbs shock, silences the sound of footsteps, and keeps the carpet “springy.” The underlay also moonlights as a moisture barrier between the carpet and the subfloor (plywood or oriented strand board). 

If liquid soaks through the fibers and into the underlay, the dampness becomes the perfect environment for mold growth. Mold—even hidden from sight underneath your carpet—will release a stale and musty smell that can begin to circulate. 

Other signs of mold include carpet discoloration, dampness, and an uptick in allergy symptoms.

Oddly enough, you may notice an unpleasant odor that smells vaguely like something you spilled on the carpet recently. This happens when bacteria feed on the spill and release gasses. Though you can technically use deodorizers like Febreze to improve the carpet’s smell, they won’t necessarily get rid of the odor.

Carpets Release Foul Smells as They Get Older

Beyond lingering odors stemming from spills, leaks, and high humidity, carpets can stink up an entire home as they age. Carpet can last a few years to several decades before becoming matted, frayed, and generally worn out.

Of course, with time, the fibers break down and degrade naturally. High foot traffic, sunlight exposure, moisture, and exposure to chemicals (like bleach) can all speed up this process. 

An old carpet can make your home smell musty, sour, or damp.

How To Get the Stench Out of Smelly Carpets

Now that you know carpet can (huge emphasis on “can”) make a whole house smell, how do you fix it? 

Here are some tips for de-stinkifying and preventing house-wide carpet smells:

Clean Spills Immediately After They Happen

Regardless of the type of carpet you have, the best way to prevent these odors long-term is to clean up liquid spills immediately. 

Simply blot the spill with a clean rag or paper towel to soak up as much of the spill as possible. Do not rub the area with a rag or towel. 

Rubbing the spill may make it appear to “dry out” sooner, but doing so can also force the liquid even deeper into the fibers and underlay. This opens you up to many problems in the future, such as mold or mildew growth and unpleasant odors.

Mr. Siga Microfiber Cleaning Cloths are definitely the way to go when blotting up carpet spills (link brings you to Amazon). These cloths (which come in a 12-pack) are super-absorbent, non-abrasive, and can handle just about any cleaning task. As you can see in the image above, mine are still kickin’ after over a year of daily use!

What you do next really depends on what spilled and how long it had to soak. In any case, you’ll want to neutralize any potential odor-causing molecules. 

Use a Natural Deodorizer To Neutralize Bad Smells

You can also use a host of all-natural deodorizers to neutralize bad odors at the source. 

Baking soda, for example, can absorb bad odors and moisture. All you need to do is simply sprinkle some baking soda the smelly areas of the carpet and work it into the fibers with a brush or sponge. Then, suck it up in a few hours with a high-power vacuum.

Vinegar is another saving grace for smelly carpets. It’s acidic enough to break down odor-causing molecules within the carpet’s fibers. Just dilute some distilled white vinegar in water (1:1) in a spray bottle, spritz it onto the affected area*, let it sit for about 10–15 minutes, and then blot it up with a clean rag.

* Make sure you first test the solution on a small area of your carpet. The carpet industry remains torn on whether vinegar can discolor carpets, so err on the side of caution here!

Vacuum Your Carpets Weekly

A carpet’s fibers will hold onto everything from natural dust and dirt to strands of hair, food crumbs, dead skin cells, and sweat. All of these also release a not-so-pleasant odor as they decompose. 

Regular vacuuming can prevent the build-up of this dirt and dust. Try to vacuum at least once weekly. Of course, if you own pets, have allergies, or your home sees a lot of foot traffic, you should vacuum a bit more frequently (i.e., every other day or even daily).

Break Down Deep Smells With an Enzymatic Cleaner

Enzymatic cleaning products have one distinct purpose. They use enzymes to break down and eliminate (rather than mask) specific types of molecules or organic material, especially those that cause bad smells. These cleaners are particularly useful against pet accidents, food spills, sweat, and vomit.

Lower the Indoor Humidity

High indoor humidity is essentially a recipe for disaster in the world of carpet odors. The carpet’s fibers can hold onto more moisture at high humidity levels. This moisture creates the perfect environment for mold, mildew, and bacteria.

The EPA considers 30–50% humidity “ideal” for preventing mold or mildew (along with other perks, such as fewer indoor pests). But, of course, actually lowering indoor humidity can be much easier said than done if you live in a tropical area. 

The simplest way to dial down indoor humidity is to open interior doors. This method is particularly useful if certain areas of the house are naturally humid. Open doors will also allow for more airflow throughout the house and, in turn, replace the stale air with fresh(er) air.

A dehumidifier is another possible solution—albeit a pretty expensive one. Dehumidifiers pull excess moisture out of the air while spitting “dryer” air back into the room. 

One possible lower-budget fix is introducing a fan into a room with stale air caused by an overly moist carpet. Though not as effective as dehumidifiers, fans will enhance circulation and encourage evaporation. They’ll also pull the moisture away from surfaces—like your floor.

Turning on the air conditioner can also pull excess moisture from the air on a more regular basis.

wall air conditioning unit

Will Replacing Carpet Get Rid of the Smell?

Replacing carpet will typically get rid of the smell if the source is confined to the carpet’s fibers and other carpet cleaning methods haven’t worked. Thus, replacing the carpet won’t fix the smell if spills soak through the fibers and underlay into the subfloor. You may need to replace the padding underneath the carpet to address deeply penetrated odors.

Final Thoughts

Carpet can absolutely give a home a sour, stale, or musty odor. Everything from basic spills to pet stains to ultra-high indoor humidity levels can cause this.

However, there are many ways to prevent this house-wide odor caused by your carpet. With regular care, maintenance, and quick clean-ups, you can avoid these carpet smells and keep your whole home smelling fresh!

If you’re simply not sure whether your carpet (or anything in your home) reeks, read my post How Do You Know if Your House Stinks? to learn how to smell what your guests smell.