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Mould in Houses: 6 Reasons Why it Grows – Clear Proof

Having mould in houses has hit the headlines frequently in the UK in recent years on both the local and national news on TV and the newspapers and it is certainly an issue not to be taken lightly.

In this useful guide, we’ll help you to understand the main potential cause of mould in houses and share other useful information to help you understand mould problems (including mould spores) in more detail.

Mould in Houses
Mould in Houses – Causes Explained

As well as being experts in leak detection, we also offer a wide range of property restoration services and one of those is delivering help and guidance with a wide range of damp and mould problems to our customers locally.

Why Stop Growth of Mould in Houses?

It might seem obvious as to why you might want to stop mould in houses, but just in case you didn’t know. Mould can pose a serious risk to health to occupants. In fact, on the NHS Damp and Mould page, they themselves say that “Moulds produce allergens (substances that can cause an allergic reaction), irritants and, sometimes, toxic substances”.

They add “Inhaling or touching mould spores may cause an allergic reaction, such as sneezing, a runny nose, red eyes and skin rash. Moulds can also cause asthma attacks”.

Stop Mould in Houses
Stop Growth Mould in Houses

So you can see how it needs to be taken seriously, and as we have said elsewhere, prevention is better than the cure. As we will see later, mould needs certain climatic and environmental conditions to grow so it is best to stop those factors being a risk for mould growth in your home or business.

Potential Health Risks from Mould in Houses – Factors

Like other types of allergen, there isn’t necessarily a ‘one size fits all’ on how mould in houses will effect people, but there are things that could contribute to the seriousness of the issue for different types of people.

Mould Health Risks
Potential Mould Health Risks

Here’s a few examples of possible things that could impact how severely a person is affected by mould (and some are related to each other):

  1. The amount of mould and mould spores in houses – volume and surface area
  2. The length of exposure to the mould problem (short versus long-term)
  3. How close to the mould is to the person (e.g. mould on walls near where you sleep)
  4. The variety of mould that is growing (there are many with some more dangerous)
  5. Individual susceptibility to mould (like allergies this varies person to person)
  6. The health and age of those coming into contact with mould spores
  7. Other factors that could affect health or having other illnesses (especially respiratory)
  8. General environmental conditions in the property – e.g. is it cold and damp?

Clearly this is a complicated area with a variety of factors to consider, but some of these things above may contribute to the effect of mould in houses has on people’s health. For example, an elderly, asthmatic person in a cold house, with a long-term exposure to large amounts of mould may be at more risk than a younger, healthier person with a small amount of short-term mould.

Unfortunately, in some situations, mould can even lead to death. As was seen in the death of a young child in Rochdale, Greater Manchester a few years ago – see this article from The Independent. In that article they explain how the coroner said the death was as a result of “prolonged exposure to mould in his home”.

Clearly, if you are worried about how mould in your property or suspect it could be affecting your health, get help from a medical professional. As we saw earlier, the NHS page has very useful information and advice. You can also contact us for help if you have a problem with mould in your house, more on that later.

Now let’s look at the most common causes of mould in houses in the UK.

Causes of Mould in Houses
Common Causes of Mould in Houses

Causes of Mould in Houses – 6 Common Factors

Just like the health affects of mould in houses, the causes of mould can be varied and not always simple to diagnose, but as experts in mould remediation services, here are things we come across. We talked about this more in our article about how to stop mould on walls.

Some things that might contribute to mould in houses:

  1. The presence of mould spores (more on that later!)
  2. High levels of moisture and humidity – see how to reduce humidity
  3. The presence of a water leak, causing damp – e.g. a bath ceiling leak
  4. The right levels of temperature – see our mould in winter guide
  5. Poor ventilation and air movement – can cause condensation
  6. An organic substance to grow on – like damp plaster
  7. Lack of contact / disturbance – areas not cleaned often
  8. Little or no direct sunlight – it often ‘prefers’ dark, damp, shady places

One of the things we mentioned is condensation, you may find our guide on what is condensation useful too as that is a more common cause of mould than you might think.

Test for Spores from Mould in House

First on our list of contributing factors to mould in houses above was the presence of mould spores. Spores for mould are a bit like seeds for plants. Mould spores are a way for mould to spread in areas and, given that they are very small, they can disperse in the air. We discuss this in our article about air quality meters.

There is a really good demonstration of this in this YouTube video from the BBC:

Mould Spores Being Spread

If they land in a place with the right conditions they can grow and spread, especially if the conditions persist. Again, like a seed for a plant finding water and soil to grow in. If you just kept a seed dry and with nothing to grow on, it’s far less likely to actively grow (if at all!)

You might not realise but it is highly likely you have mould spores in your property, even if you do not have active mould growth. Mould spores are commonly found in both indoor and outdoor environments and can spread from one to the other. We set out to prove this!

Testing Mould in House
Testing for Spores from Mould in House

Here is what we did in our experiment looking for mould in houses, more specifically the presence of mould spores in houses:

  1. We selected 3 random areas to take sterile swab samples from
  2. The first was a door mat (where people may bring spores in from outside on their shoes) for example, if you’ve been walking on grass, or in woods, there can be mould on rotting vegetation.
  3. The second was a table top, to see if mould settles or blown in the air from one area to another.
  4. The third was taken from a plant that was in the property, swabbing on the leaf and soil
  5. Just to stress, this property did not have active mould growth or mould problems
  6. We then wiped the swabs in three separate petri dishes and incubated them
  7. The substance in the heated incubator petri dishes was ‘Agar Agar’ a good growth medium
  8. We left them for one week and checked back afterwards

Here are the results:

Mould Test Results
Mould Test Results from Swabs

As you can clearly see, there is active mould growth in all 3 of the dishes. However, by far and away the worst was the first sample (on the left) taken from the doormat. Whereas the other two samples had relatively small amounts of white coloured mould growing, the other had large patches of dark black mould.

In some respects, because of what we mentioned earlier in this guide, this is not a huge surprise, even in a clean house with no issues with mould. Mould spores are largely omnipresent, it is almost like dust in your home, no matter how clean it is, it’s extremely unlikely you will have zero dust at all, and even if you did, soon after some would appear.

You can understand why air scrubbers (air purification and filtration systems) play an important role when carrying out mould remediation work in properties, their HEPA filters help to remove mould spores from the air.

Mould Survey Services

If you have a problem with mould in houses or businesses, we can help you. We offer both mould surveys and mould removal services in York and the surrounding area, as well as our professional local water damage services.

Our staff are experienced at dealing with a wide number of damage management services, including mould inspections and mould remediation. They know what to look out for to help diagnose the causes of mould in houses locally, and importantly, pinpoint specific causes and remedies to help greatly reduce the risk of mould.

Mould Survey Service York
Mould Survey Service York

Remember, if the cause of the mould in the first place is not dealt with, then the risk of mould returning is far greater, simply cleaning mould off and not tackling the cause (like a water leak or damp) is not sufficient or as good as a longer term, preventative solution to avoid problems with mould in houses.

On top of that, if you have a mould problem we also offer mould removal services to carefully and safely remove mould, which is obviously important. We use specialist equipment and antimicrobial solutions to help deal with mould problems. More on that next.

Mould Removal Service York
Mould Removal Service Based in York

Mould Removal Service in York & Yorkshire Coast Area

We offer a comprehensive mould removal service in York and local area and can help with:

  • Mould on walls
  • Mould on ceilings
  • Mould in bathroom
  • Mould in bedrooms
  • Mould in other locations (homes or businesses)

We provide this service locally to domestic and commercial customers. We also help with landlords and tenants with mould. In fact, we are a recognised service provider for the York Residential Landlords Association. Their members trust us to deliver this service, and so can you.

York Residential Landlords Service
York Residential Landlords – Service Provider

Our staff are trained, experienced and have access to professional tools and equipment to deal with mould problems efficiently and effectively. Our team will help explain the process to you from start to finish, so if you need help with mould, contact our team for assistance.

Mould in Houses- Top Tip
“When it comes to mould in houses, prevention is better than cure. Mould needs certain conditions to grow and flourish in houses so preventing those conditions, in particular damp, water leaks and condensation issues will greatly help to prevent mould growing.”

Leak Detection Team

Mould in Houses – Conclusion

As we have seen in this guide, mould in houses is a serious issue with a number of potential contributing factors and possible consequences. Mould and mould spores are common in both indoor and outdoor environments but the key thing is to not provide them with the right conditions to grow. And then, if you do have a mould growth problem, get it dealt with safely asap before it gets out of hand.

We showed how even a clean house with no mould issues can have mould spores present, it then might only take something like a water leak in your home to make a surface such as a wall, floor or ceiling to become wet as a result and mould can grow. Remember, this might even be in a place where you cannot see, it is not unusual to see mould in underfloor spaces, or in wall cavities etc. Or even mould behind wardrobes etc.

Rainbow Restoration Mould Removal
Rainbow Restoration – York & Yorkshire Coast, Mould Removal

Mould in Houses – associated articles related to potential health hazards in the home:

Each of these articles provide useful information about (a) some of the services we offer to our customers and (b) some useful information about risks that can be posed from things in your home. We are experts at dealing with many of these risks and have dealt with them frequently, when you use our services, this experience is valuable.

We really hope you found our guide to mould in houses informative. Please feel free to contact us for help at any time and we can explain the process involved in this or our other services, such as our Trace and Access service.

At Rainbow Restoration – York & Yorkshire Coast we are experts in Fire and Flood restoration and in Flood Damage and also Water Damage Restoration, so if you need help getting your residential landlords association property back to normal after an incident, get in touch with our friendly local team who will be happy to help you with this. We are based in York and help find water leaks in York.

Leak Detection Logo
Leak Detection Logo

Mould in Houses – Useful FAQs

How do I stop mould in my house?

Mould Removal - York, North Yorkshire

In order to stop mould in houses, the most important thing is to identify the cause of the mould. Mould needs specific conditions in which to grow in the first place and one of the main factors is a source of moisture, which could be damp, condensation or even a water leak. If it is caused by a water leak, you need to find and fix the water leak, which is where a leak detection service like us helps too.

How serious is mould in houses?

Damp and Mould - Removal, York and Yorkshire

Mould can be a risk to health, especially if there is a lot of it and exposure to it is prolonged. Additionally, certain people are more at risk, such as the young or elderly, especially if they have underlying health problems, and even more so if those problems are respiratory. Different people react to mould in different ways and there are a very large number of mould varieties so each case is different. It is advisable to get help from a mould expert to help remove bad mould in houses.

Is it normal to have mould in your house?

Damp and Mould - Walls, York and Yorkshire

In normal circumstances, a house that is well maintained, has good ventilation and no issues with damp or water leaks shouldn’t normally have mould. That said, mould is not exceptionally rare either, especially in winter when condensation is often more of an issue. The key thing is to help prevent it and, if you do get mould in houses, get on top of it asap to prevent it spreading or causing health issues.

Our friendly, local team are just a phone call away and will be happy to discuss your needs and how we can help you with any problems you have with your home. We have a highly experienced team who have dealt with many of these issues, including mould in houses, for many years and that is invaluable knowledge that can assist you.

We are trusted and used by several of the UK’s top insurance companies as well as a number of other local organisations such as property management companies and other local businesses. They trust us to deliver an excellent service for their customers, and so can you.