Understanding the causes and risks of mould in your home will seriously make you want to take action!
A home - even a modern one - can be damp for many reasons:
- Very obvious scenarios would include water damage from leaky plumbing or flooding, but in most cases the cause is more hidden.
- Poor house design can lead to water slowly leaking in over a prolonged period of time, often in hard to get to places such as the ceiling or the framing around windows and doors;
- Poor insulation can lead to cold spots within the construction where condensation can form unnoticed;
- The use of building materials that don't regulate humidity or trap moisture, such as drywall painted with acrylics;
- Poor ventilation can lead to substantial condensation of moisture introduced to the home by its occupants, especially in kitchens, laundries and bathrooms.
- and while increasing the air tightness of buildings helps with energy efficiency, it exacerbates the problem arising from poor ventilation.
Indoor air quality
Many factors influence indoor air quality (IAQ), including gases, particulates, and in this case microbial contaminants. Controlling indoor air humidity plays a vital role in creating a healthy home. The recommended "Comfort Zone" for relative humidity in the home is 40-60% RH. Deviations from this range can coincide with increased levels of bacteria, viruses, mould and other factors that reduce air quality and lead to health problems. Some indoor air quality specialists recommend that relative humidity be maintained at less than 55% to control fungal proliferation.
What are the possible health effects of exposure to mould?
The fungal spores produced by common mould species are linked to some serious illnesses. A damp home doesn't only increase your risk of developing a respiratory illness such as asthma, it can actually cause a biotoxin related illness called Chronic Inflammatory Response Syndrome.
People often report a cluster of nasty symptoms, such as
- joint pains
- abdominal pain
- decreased brain function
- extreme mood swings
- and a weakened immune system, just to name the main ones.
Mycotoxins can cause adverse health effects at very low concentrations. Some of the moulds that are known to produce mycotoxins are commonly found in moisture damaged building materials. Exposure pathways include inhalation, ingestion and skin contact.
28% of people have a genetically influenced innate immune response that gets turned on by environmental mold, but it doesn’t turn off. If you’re one of these people, if you get exposed, you get sick, and you won't get better until the problem is remedied.
The good news is, creating healthy, dry living conditions isn't hard or expensive...
Develop good habits
Make ventilation part of your daily routine
The simplest and cheapest way to ventilate is to open doors and windows regularly to allow fresh air from outside into your home.
In winter, cross-ventilate your house at least once a day for a few minutes with wide open doors and windows. To avoid condensation problems, do this when you turn off the heating - for example, before you leave the house in the morning and just before you go to bed at night.
Sort out your bathroom, kitchen and laundry ventilation
The most significant sources of moisture in your home are the kitchen, bathroom and laundry.
Consider fitting extractor fans in all these rooms (placed as close to the moisture source as possible). Make sure they vent to the outside, not into the roof space. Because extractor fans remove moist air but don't bring in fresh air to replace it, you'll need some other way of getting fresh air into the room.
Alternatively get into the habit of opening a window after you have taken a shower or when you cook.
This might sound obvious... but if you suspect ongoing water damage, get to the root of the problem. Sort out leaky plumbing, inadequate flashings, blocked down pipes and so on.
Avoid using unflued gas heaters
They release large amounts of moisture and toxic combustion gases into your house.
Keep furniture away from external walls
Leave a gap of 100mm or more behind large objects like furniture and keep mattresses off cold floors to enable air to circulate.
Look for mould regularly and remove it if you find any
Regularly check for signs of mould in your home. Places to look out for are windows, bathroom tiles and behind furniture and paintings. If you find any mould, clean it off using a natural fungicide such as borax, vinegar, baking soda or hydrogen peroxide.
Incorporate thermal mass
In order to have a healthy, dry home ideally you get the basics right: Buildings need to be weather tight, well insulated and allow for adequate ventilation. If you are building from scratch, this should be common practice. One thing however that is commonly overlooked is thermal mass.
Thermal mass regulates temperature by absorbing heat when it is available, storing it and slowly releasing it when ambient temperatures drop.
Keeping temperatures higher and more constant reduces condensation and dampness, because cold air holds less moisture and so will condensate on windows and walls.
Earth is one of the best thermal mass materials available, because of its slow reaction time and because it naturally regulates humidity.
It is easy to retrofit earthen building elements to your existing home: Earthen plaster over drywall, inbuilt cob furniture or mudbrick feature walls - let your imagination run free while creating a beautiful, healthy living space.
Use clay to regulate humidity
You can't beat clay when it comes to balancing indoor humidity at optimum
levels of 40-60% RH. A solid wall of earth bricks can absorb up to thirty times the moisture of conventional burnt bricks and a 30mm thick surface coating of clay is more than enough for daily buffering.
These remarkable moisture buffering properties may cause people to believe that clay building products, by absorbing moisture, would be setting up the perfect conditions for the growth of mould, however the opposite is true: Ideal conditions for mould or rot are caused when a building material absorbs moisture and is unable to later release it, or when moisture is not absorbed but condensates on a surface.
Using clay in your kitchen or bathroom (away from splash zones) is hygienic and will prevent mould growth.
Natural materials are a great choice for DIY. My mission is to make them accessible to anyone with a desire to create their unique, healthy living space... With some guidance, you can source materials locally and learn on the job - all while having a lot of fun!
Work with naturally anti-fungal surfaces
In areas that are often damp, a possible plan of action is to switch to naturally anti-fungal surfaces, such as lime plasters or Tadelakt.
Lime is highly alkaline and inhibits mold growth. It can be used to fix mould problems in old buildings (once permanent water damage has been remedied) and is a good and very hygienic choice for bathrooms - even in splash areas such as hand basins and showers.
Lime plaster is water resistant and can be applied as Tadelakt, for a totally water proof result.
Working with lime - especially in situations where water proofing is required - is a bit more technical, so it is advisable to get a skilled person onto the job.
Check your home for mould today! It could make a huge difference to your quality of life...
- If you spot mould in your bathroom, kitchen or laudry - CLEAN IT
- Get into the habit of properly VENTILATING
- Consider incorporating EARTH and LIME into your home to regulate humidity, prevent condensation and inhibit mould growth
Please help raise awareness about mould by sharing this blog post. Have you got mould problems in your home? What do you do to keep your living spaces dry and healthy? Leave me a comment below...