Why Does My House Smell When I Open Windows?

Why Does My House Smell When I Open The Windows?

We all know that feeling; it is a hot, stuffy day and all you want to do is open a window to allow some fresh air in and to feel a cool breeze drifting through the house. However, along with the cool breeze and fresh air is a horrendous smell. 

Although you do not know where the odor is coming from, or what may be causing it, to keep your house from smelling worse, the smell forces you to close your windows. 

Why does my house smell when I open windows? Your house smells when you open the windows based on factors that are both inside and outside your home. Possible reasons why your house smells when you open your windows include plumbing issues, rotting wood, dead animals, and bacteria. Industrial and environmental factors may be responsible as well.

In this article, we will explore a few of the possible causes of these horrible odors and what you can do to try and eliminate them.

Where Do the Bad Smells Outside Your House Come From?

Human settlements such as cities, towns, and villages are growing at a tremendous rate, so we are continually building infrastructure to accommodate the ever-increasing population. 

As a result, humans have begun to encroach upon some lands that are not well-suited for human habitation. 

During the Industrial Revolution, as people began establishing more and larger cities, towns, and villages, structures such as power plants, sewage works, and industrial areas were all necessary parts of the equation.

Planners believed that the land used to develop these services would be well away from where people would live.

While access to infrastructure was critical, city planners did not want to cause any inconvenience or distress from noise or air pollution to the residential population.

While we associate bad smells with industry and development, it may come as a surprise that nuisance smells can originate from other, more natural sources.

Living in the countryside may sound idyllic but, if you are not used to the smells of the country, life may not be so pleasant. For instance, living next door to a farm has a unique set of odors.

Even that cute, sea-side fishing village that you dreamed about moving to, or living somewhere close to the beach, can come with its own set of odors, and not all of them pleasant.

So, where do these terrible smells come from?

Sewage works

Sewage works are an unfortunate fact of life. Most people will live far enough away from their local sewage works and will never need to take into consideration the smell before moving in. 

However, if you live reasonably close to a sewage plant, there may be some days when the wind blows from the wrong direction causing a bad smell in your house. 

While the emissions from sewage works are tightly regulated and will not cause you any serious harm, the smell can be quite intense and extremely overbearing.

Oil Refineries & Oil Fields

There are many suburbs across the United States that have grown around existing oil fields and refineries. For example, in California, the densely populated Los Angeles Basin is still a very productive oil-producing area. 

While oil production is dropping, LA county still managed to produce 18 million barrels of oil in 2018. The residents have had to learn to live side-by-side with oil-producing facilities, but at what cost (source)?

While oil refineries and oil fields have to operate according to strict air quality controls and health and safety standards, they do produce strong nuisance odors. 

Despite the industry adhering to strict government regulations, people living close to oil refineries often complain about the strong odors. 

Residents also complain of watery eyes, headaches, nausea, and other irritations that force them to close their windows and stay indoors.


Living next to a brewery may sound awesome; some people think there is nothing better than the smell of freshly brewed beer. 

However, you should take into consideration that all breweries can, and often do, produce strong odors at times. These odors can be quite unpleasant if you live next to or close to a brewery. 

Fermenting beer produces all kinds of weird and wonderful smells. Some people do not mind the strong, sour, and sometimes fruity smell produced by the fermenting yeast, but other people cannot stand it, and the odor may also make them feel ill. 

However, breweries are required to operate under strict environmental standards, and the smell will not cause you any harm.

If you do not like the odors produced during the brewing process, then you will be keeping your windows closed as tightly as possible.

Gasoline and Diesel Exhaust Fumes

Most people will naturally associate gasoline and diesel exhaust fumes with vehicle emissions, especially if you live next to a busy road or intersection. 

Yet gasoline and diesel exhaust fumes, or carbon monoxide, come from any internal combustion engine source, which also includes generators, gas heaters and the furnace in your home (source).

Typically the exposure to harmful doses of exhaust fumes in the home is minimal. However, if you do use a home generator, gas heater, or home furnace, make sure you place a carbon monoxide (CO) detector close to the installation of these appliances (source).


Access to the internet is becoming more widely accessible and more user-friendly. Many people, previously urban and suburban dwellers, are taking advantage of online work and businesses, which enables them to relocate to the countryside. 

This migration to the country inevitably leads to conflict with the local farming communities over foul or nuisance odors.

Intensive animal farming, different kinds of animal manure, fertilizers, and pesticides can all cause strong or nuisance odors that farmers say come with the territory.

If you’re thinking of moving to the country for the “clean air,” you will have to take into consideration the “fresh” country smells (source).

Sea-Side Smells

When we think of the beach or the ocean, our imaginations never fail to conjure up images of sand and sunshine, and the smell of salty, clean air.

If you are fortunate to live close to the coast, there is nothing better than throwing all your windows open and letting that fresh sea breeze sweep through your home.

Nonetheless, bad smells on the beach do exist. If you have ever been unfortunate to live or stay downwind from a fish factory or a beach full of rotting seaweed, your windows will be kept firmly shut. 

On the positive side, the wind will change direction, and the tide will come back in, so the foul odors are not permanent, and you will be able to open your windows again.

What if the Smell is not Coming from Outside?

A bad smell when you open the windows, is not necessarily coming from outside the house. Even if you keep your house spotlessly clean, that terrible smell could be coming from inside your home.

It is possible that the smell is an isolated one, limited to only one or two rooms, and you may not find it throughout the whole house. However, you will still need to know the cause of the odor to be able to eliminate it.

If you cannot trace the smell to anything obvious, like a stale cooking smell or a pet, there may be a more serious underlying problem. 

If the smell only occurs when you open the windows, then you can ascertain that the source of the scent needs the draft to draw it from its location.

The following are the most common locations of a bad smell emanating from inside your house.

A Blocked Drain

A blocked drain can make your house smell like a sewer. If you have a sewage smell in your house, it means that there is hydrogen sulfide present, which can be dangerous even at low levels. 

Symptoms of prolonged exposure to mild sewage gases include — but are not limited to — irritability, headaches, tiredness, and loss of appetite.

You can easily unblock most blocked drains by pouring a combination of baking soda, vinegar, and boiling water into the drain that smells. 

A Blocked Plumbing Vent

In addition, a blocked plumbing vent will also cause a sewer-like smell to permeate your house. Other signs of a blocked plumbing vent will include spluttering taps and toilets. 

Clearing a blocked plumbing vent can be straight forward, but will involve climbing onto your roof where the vent exits your house. 

You can check for and manually clear any visible blockages like dead birds, birds nests, or leaves. Otherwise, you will need to flush the plumbing vent system, which is not difficult to do, using a hosepipe. 

Remember, do not climb onto your roof without someone else there to assist you (source).

Bacteria in Your Water Heater

If you notice a rotten-egg or sulfur-type smell when you are running your hot water taps in your house, then you may have a bacterial growth inside your water heater.

Bacteria can survive inside your water heater without oxygen. This bacteria reacts with the sacrificial anode rod, which is a metal rod that is installed inside every water heater to reduce corrosion. 

The reaction between the bacteria and the metal rod produces small amounts of hydrogen sulfide, which gives off that rotten-egg smell. 

To reduce the risk of the bacterial reaction and the rotten-egg smell, you should replace these sacrificial anode rods regularly and according to the manufacturer’s specifications.

Rotting Subfloors

A subfloor is the rough surface underneath your finished flooring material, whether tiles, laminate, vinyl, wood, or carpet. 

The subflooring is most often hidden from view. Because of this — unless there is a severe or obvious problem like your carpet showing mold or a laminate floor lifting — a slowly rotting subfloor can be challenging to detect. 

Depending on the material used for your subfloor, a rotten subfloor will make your house smell of damp or mold or both. Depending on the severity of the rot, it may be necessary to replace or repair parts or the whole of your subfloor.

Dead Animals

If you think your house smells like an animal has died somewhere, then it probably has.

It’s not uncommon to find dead animals in chimneys, air vents, plumbing vents, under the stairs, inside drywalls, and in just about any other opening or space you can think.

If you suspect you have a dead animal in some part of your house, you will have to call in the experts as you can pretty much guarantee it will be in some dark and challenging place to reach. 

A Pest Infestation

No, it is not your imagination; that strange distinctive odor that you can’t quite put your finger on could mean that you have a pest infestation. An infestation can happen even in the cleanest of homes. 

Pests need three things to survive: food, water, and shelter, all of which you could be unconsciously providing. 

Rats or mice could be eating your pets’ food; cockroaches could have been brought inside in shopping bags or cardboard boxes and are now feasting on crumbs and leftover food in your sink. 

Each pest comes with its own distinctive smell. Experts say that mice give off a musty, urine smell. In contrast, rats smell like ammonia, and some describe cockroaches as having an “oily” odor. 

Whatever may be the cause of the smell inside your house, in most cases, you will need to hire an expert. An expert will identify and solve the problem and help you to improve the air quality inside your house (source). 

Can Bad Smells Be Harmful to My Health?

Natural bad smells are not necessarily harmful, but chemicals that produce a strong odor may be detrimental to your health.

In most instances, people will notice or smell bad odors before there is a risk to their health. Most everyday bad odors will contain very low concentrations of chemicals that are not harmful to your health at all. 

Also, people react differently to different smells, and everyone is not equally sensitive to the chemicals that they may contain. An odor that does not bother you may be the cause of a more severe reaction in someone else.

Whether or not someone experiences health problems from a particular chemical will also depend upon several factors. These factors will include what the chemical is, how concentrated it is in the air, and how long the exposure to the chemical lasts. 

What Symptoms Can I Expect?

Prolonged exposure to bad smells and chemical odors will cause a range of symptoms from very mild to more extreme.

Symptoms you can expect are:

  • Headaches
  • Nasal congestion
  • Eye, nose, and throat irritation
  • A sore throat
  • Coughing
  • Chest tightness, shortness of breath or wheezing
  • Heart Palpitations
  • Nausea and lack of appetite
  • Drowsiness
  • Mental depression or stress

Bear in mind that health symptoms caused by bad smells usually go away quickly when the exposure to the odor stops (source).

What Can I Do to Get Rid of the Bad Smell in My House?

The way you deal with bad smells in your house will depend on whether the source is from inside or outside your home.

Getting Rid of Outdoor Smells

It may sound simple, but when you first notice a bad odor coming from outside, the first thing to do is close your windows. Closing your windows will help prevent the smell from getting into your house.

Another possibility is if you have an air conditioning or ventilation system. Set it so that it circulates the air from inside your house and does not draw air from outside. If you have ceiling fans, switch them on.

If the bad smell from outside becomes more frequent and keeps you indoors more often, you may consider contacting your local authority to investigate the source.

Getting Rid of Indoor Smells

Getting rid of a bad indoor smell will mean determining the source and solving the problem before the smell will go away. It may be something as simple as regularly airing your pets’ bed or relooking at your garbage disposal system. 

While you are solving the problem, try opening windows and using fans to increase air circulation. Doing this will help improve the air quality and reduce the bad smell in your house.

Temporary Measures

Using temporary measures to get rid of the bad smells in your house may include opening windows and using air fresheners, scented candles, and essential oils. 

However, while opening windows to let in some fresh air is a good idea, these other solutions are a temporary fix. They will just mask the smell rather than making it go away.

Be sure to check out our article on what happens if you never open your windows.

Final thoughts

Regularly opening your windows is essential for a healthy house and will generally improve the air quality inside your home.

While I have given possible reasons that your house will smell when you open the windows, only extreme cases should cause you to really close up.


I'm a Pharmacist and a passionate researcher into clean air and pure water for the home. I believe these 2 elements play a significant role in our health and overall wellbeing.

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