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Why Your House Smells After Winter

Winters are often long and cold in many cities in the U.S., and during these long chilly days, it makes sense that all windows and doors are shut most of the time. While keeping the doors closed and the windows sealed is a great way to keep the indoor temperature in a pleasant range, this practice also considerably increases indoor humidity. Without any ventilation, the water vapor present indoors ends up 0n walls, furniture, and other objects creating a wet and musty sell in the house. If this smell occurs solely due to increased humidity due to closed windows in winter, then some ventilation should help. However, if the musty smell persists despite ventilation or gets even stronger, then this is a huge indicator of mold and mildew.

Causes Of Smells In The Home After Winter

Many things can increase the humidity in your home, especially during and after winter. These factors eventually provide an extremely cozy environment for mold and mildew to thrive, resulting in a musty smell spreading out through your abode. This smell is typically lighter during winter as the use of heaters is at its peak, but as winter fades away, the musty smell keeps getting stronger. Moreover, this smell may get stronger than ever when you vent your home after winter.

Here are some of the most common factors that contribute to moisture and musty smells in a home.


The huge difference between indoor and outdoor temperatures during winter potentially causes water condensation around windows, providing just the right conditions for mold to grow. This gets even worse every time a window is opened or closed. Moreover, this problem can amplify even further if your window isn’t properly closed, as any leaks can allow rain and snow to get it.

Air Pollutants in the HVAC System

Your HVAC system is put to good use during the hot and cold seasons. However, these systems also have favorable conditions for mold growth that can result in humid and moldy smells. HVAC systems are warm and humid, hidden from light, and have the potential to collect a lot of dirt that serves as a good source of food for mold. So, it’s important to keep your vents clean and change the filters at the right time to prevent dirt from accumulating.

Leaky Pipes & Clogged Drains

Leaky and dripping pipes and faucets are by far the most common sources of excess humidity in a home that lead to mold growth. If you notice closely, musty smells usually emanate from the kitchen, bathroom, and other areas in your home with any water sources. In winter, rancid smells coming from your bathroom or kitchen drain might fill up your home and intensify, even more, causing mold and mildew development.

Wet Clothes and Footwear

In many areas, there’s no possibility to hang out your laundry to dry. With heavy snowfall outside and the absence of a dryer, you have to succumb to hanging your laundry inside your home. Wet clothes release high amounts of moisture in the indoor air. Additionally, wet coats and boots covered in snow or drenched in the rain are also common sources of moisture that need to dry after every trip outside. All this evaporated water accumulates indoor, leading to mold growth and musty smells.


Pets can also cause your home to smell musty. If your dog likes going out to play in the snow, its fur will naturally be wet. Moreover, its paws may also trek groundwater inside your home. So, every time your pet enters your home with damp or wet fur, they contribute to the moisture levels within your home.

How To Fix The Problem?

Keep A Check On All Leaky Fixtures And Fittings

It’s imperative to keep a close check on all fixtures and fittings, especially faucets and pipes, to prevent dripping water which is the leading cause of moisture. Get all your kitchen and bathroom fittings inspected before winter commences so that you don’t have to bear musty smells throughout the season.

Invest In A Dryer

If the winter season in your area means continuous snowfall, then it’s best to invest in a dryer for your clothes. Since hanging your wet clothes and laundry in the house contributes greatly to indoor humidity and smell, the best option is to put your wet clothes directly in the dryer after washing them.

Get Your HVAC System Checked

While an HVAC system is a great asset that can help you survive through winters and summers, you need to ensure that it runs efficiently. An inefficient HVAC system can cause the growth of mold and mildew. So, it’s important to get your HVAC system regularly cleaned and serviced, allowing it to work efficiently.

Let Some Fresh Air In

Your house can feel quite stuffy during the winter due to the locked doors and shut windows. The best option for you is to open up your main door to allow fresh air and sunlight in. The ideal time to do this is early in the morning when the sun shines bright. No matter how clean your home is, proper ventilation is the key to keeping mold and mildew at bay.

The Bottom Line

Keeping moisture levels low in a home during winter can be quite difficult, considering the various water sources present indoors and outdoors. This, combined with poor air circulation and ventilation, and a huge difference between indoor and outdoor temperatures, contributes to the occurrence of musty smells, which can persist way after the winter season ends.