House Smells Musty After Rain -Mildew ,Dampness & Septic Sewage Smells

Does your House Smell Musty Every Time it Rains? Perhaps you can even smell Mildew or Septic smells?

In this guide you will learn:

  • Why Does your house or basement Smell Musty after rain,
  • How to Identify the Cause of the must smell in your home after rain,
  • Causes of Sewage or Rotten egg smell after rain in your home,
  • How to Get Rid of these Musty Smells & Prevent them in Future.

Whenever there’s a storm in your area, one of the first thing you’re sure to be worried about is how it might affect your home. If there’s been a heavy rain, you’ll especially be on the lookout for any water damage.

While most water damage is something you can see, sometimes it’s something you can smell instead.

Why does my House Smells Musty after Rain?

While it is not totally abnormal for a house to give off a musty smell for a short while after rain, if it lingers around longer you may have a larger problem on your hands.

When it rains, the moisture in the air can carry fungi and bacteria that causes the growth of mold and subsequent mildew smells.

If you can discern a smell of must or mildew in your home long after it rains, that could mean that the moisture is getting into cracks and holes in your wall, roof, or foundation.

For those who suspect this may be the case, take a look around your home to see if you do have any cracks or holes in the aforementioned places.

You should also take the time to see if there are any major leaks or puddles of water that appeared somewhere in the house. Go ahead and call an inspector if you’re having trouble doing this on your own or you think you need professional help in order to assess the damage.

Mildew smell in house after rain

When that musty smell lingers and it starts to smell more specifically of mildew, at that point mold has almost certainly started to grow.

This happens when the bacteria and fungi carried by the moisture from the rain finds a surface to latch onto.

Now the first thing you’re going to want to do is search your house to find where exactly the mold is growing. There are a number of steps you can take in order to do this including the following:

  • First check in any moist areas that are conducive to growing mold such as:
    • Under the sink
    • Behind the fridge
    • Around the washing machine
    • Ventilation ducts
  • If there’s no mold in those areas, look around on your walls or carpets to see if there is any noticeable water damage. Anywhere there’s water damage there’s likely to be mold behind it.
  • For those who aren’t sure if what they see is mold, you can buy a home mold testing kit at a number of local home goods stores

Suspecting Mold?

Call 844-994-1288 for a Risk Free estimate from a Licensed Mold Remediation Specialist in your area.

We Can Help Dry out & Repair any Water Damage as well as take care of any mold growth.


House Smells like Sewage when it Rains

A sewage smell in your home after it rains could have a couple of different causes. However, mold or mildew is not one of them.

Most likely, it is a smell coming from sewer gas caused by clogged drains or other plumbing issues. In general, there are two major reasons why this might happen:

  • One reason is because there has been a malfunction with a P-Trap. A P-Trap is a piece of plumbing that is installed in several different places in your home. They’re there to stop the leakage of sewer gas.
  • The other major reason why this could be happening is due to your septic system itself. Rather, there may be a cracked pipe that is connected to your septic system. If this happens then the gases from the septic tank are likely to seep into the open air and make the area smell.

While it is possible to fix both of these issues on your own, if you do not have much plumbing experience yourself you may want to call a professional instead.

House smells like Rotten Eggs when it Rains

Yet another commonly reported smell by homeowners is that of a sulfuric or rotten egg smell, sometimes even described as urine smell. And, just like the problem of a sewage smell, the smell of rotten eggs is often connected to your septic tank. The reasons for why you can discern the smell include:

  • Atmospheric pressure from the rain is keeping the gasses that are normal able to flow freely from the tank trapped closer to the ground.
  • It could also be due to a blocked or full septic tank
  • Conversely, it could also be due to a drain that isn’t being used

If the smell is due to atmospheric pressure then the smell should dissipate once the rain is over. If it is due to a blocked or full tank, you may want to call a plumber.

If it is due to an unused drain, then you simply need to run the water in that drain because the traps in the pipes need to be wet in order to prevent sewer gas from leaking into your home.

If your House smells Like Dirt After Rain

If you have a more mild smell that simply smells more like dirt, the cause may not be your septic tank.

This is likely caused by water that gathers around the house not draining properly.

Check the outside perimeter of your house to make sure that water is draining away from it.

Basement Smells musty after rain

Basements are likely to be a cooler more damp environment compared to other parts of the house. Because of this, mold is most common in the basement.

When it rains, water drips into the cracks in your basement causing more mold growth and musty smell.

If your basement smells like sewer after rain…

Much like when you can detect a sewer smell in other parts of the house, a sewer smell in your basement tends to be due to problems with the septic tank.

In order to try getting rid of the smell, the first thing you should do is pour some water or other liquid down any drains in the basement to activate the traps in the pipes.

How to get Musty Smells out of the House after Rain

When you do have a lingering musty smell in your house after rain, there are a couple of simple ways to get rid of that smell either temporarily or permanently:

  • The easiest temporary way to get rid of the smell is to spray an air freshener in the areas where the smell is strongest. Unfortunately this solution will only last for a short while and should only be used if you just need to cover up the smell for a short amount of time.
  • In order to get a more permanent solution to the odor, you will need to apply vinegar to the affected areas.
    • If you see any visible mold on an area then pour the vinegar on that area directly.
    • If you can sense a mildew smell in a certain area, such as a cabinet, remove any items in the area and set out a dish of vinegar to help dissipate the smell
    • Vinegar works in getting rid of mildew due to its inherently acidic properties
    • Using a mixture of water and lemon juice or any other acidic liquid would also work on getting rid of the smell

If You can’t find the source of the Musty Smell

As mentioned before, you will want to look for the source of the musty smell in any part of your house that is damp and susceptible to mold growth. Check any visible cracks in the walls or foundation as well.

If you don’t see any visible mold try looking for other signs of water damage such as chipped paint or stains.

In the event you think there is mold underneath a floorboard, carpet, or behind a wall, you will inevitably have to remove that part of the wall or flooring in order to check for sure.

You may be able to do this on your own but it is advisable to call a professional for anything you don’t think you’re capable of doing yourself.

Preventing musty smell in home

After you’ve finally gotten rid of that musty odor, you’ll probably still be wondering how you can make them stay away for good.

Thankfully, there are a number of things you can do in order to prevent that odor from coming back. These include:

  • Make sure to keep all indoor surfaces dry and avoid any sustained water damage. Remember to clean up any spills you see as soon as possible.
  • Keep the interior of your home at a stable temperature, especially if it is hot and humid outside.
  • Make sure your home is ventilated to ensure that air is moving properly. Open a window or two if you need to.
  • While not necessary, you may want to purchase a de-humidifier at a local store to control air quality automatically
  • Check for mold regularly so you can prevent any from growing before that musty smell comes back.

When to call a professional

Though you may be able to fix or get rid of some of the musty smell on your own, some things might be much easier if you hired professional help instead. For example, if you’re having trouble locating the source of the smell, a professional will be properly trained to find and detect the source of the smell for you.

In addition, if you want some help in removing certain smells or mold permanently, a professional will most likely be needed in order to have someone with the skills necessary to remove them.

We have Mold Remediation Specialists that can help Find the Source of the Musty Smell, remove any mold and prevent it from returning.

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