Moisture damage on wall.

Signs of Moisture Damage and How to Prevent It

Have you noticed a stale smell in your home or a change in the colour of floorboards, ceilings, joists or walls? If so, you may be dealing with moisture damage that can quickly have unpleasant consequences.

Keeping an eye on the humidity levels in all parts of your home and making sure your house is in good condition can help prevent this from happening. Moisture damage can quickly lead to major, costly renovations. Knowing the common signs of moisture damage can help you identify it quickly and protect your home.

What is moisture damage?

Moisture damage occurs when moisture penetrates building materials and causes decay over time. There can be many underlying causes for the damage to occur, but the most common in a house are leaking pipes, inadequate ventilation, outdoor ventilated crawl space or damage to the roof.

If not addressed, damage caused by moisture can quickly become serious. It can lead to the weakening of the building's structure and the start of a mould infestation. Once mould starts to grow, which can happen within a few days, indoor air quality can deteriorate rapidly.

Moisture-related damage can sometimes be considered a latent defect. It all depends on when the damage occurred and whether it could have been detected during an inspection. The damage can quickly become costly to repair, and insurance companies vary in whether or not they cover these costs.

Why does moisture damage occur?

There are many things that can cause moisture damage in houses. Some common reasons are:

  1. Water leakage and condensation
  2. High humidity
  3. Lack of ventilation
  4. Weather effects such as rain
  5. Lack of vapour barriers and drainage

Moisture damage can be caused by broken water pipes and old gaskets or condensation from hot water in the bathroom during long showers. Appliances such as washing machines and dishwashers can leak and damage the floor if not protected by a drip guard.

In addition, a poorly maintained or broken ventilation system can create stagnant air, which in turn leads to high humidity. There is a risk of water leakage, high humidity, flooding and condensation in any dwelling.

Where does moisture damage (usually) tend to occur?

Moisture damage damages living materials in the house. It can cause wood and floors to rot, and tiles to come loose when joints crack. Worst of all, moisture is an excellent breeding ground for moulds that thrive in moist organic materials.

It is therefore important to know where to keep an extra eye out for moisture. Visible moisture damage often occurs on facades, roofs and floors. There are certain areas in homes that are particularly vulnerable and these are:

  • The crawl space - An outdoor ventilated crawl space is particularly vulnerable in spring and summer when warm air condenses on cold surfaces. Soil moisture also rises from the ground and can damage crawl spaces and storage rooms that lack moisture barriers and good drainage. Read more about damp in the crawl space.
  • The storeroom - Unheated and poorly ventilated storage rooms are susceptible to both moisture and condensation.
  • The basementMoisture damage in basements may be due to poor drainage.
  • The garage - Moisture is often caused by poor ventilation or condensation as garages are less well insulated. Check our article on damp in the garage and tips on what to do.
  • Cold wind - Often poorly insulated and ventilated, leading to condensation during the winter months.

To avoid dampness in these parts of the house, you can carry out regular inspections, fix deficiencies and set up a dehumidifier as a preventive measure.

Moisture problems can also often occur in boats and holiday homes used for short seasons. These are left unheated during the winter and are not visited often enough for moisture to be detected in time.

Signs to look out for

There can be several signs of moisture damage. Knowing the most common ones will make it easier to look out for them and detect moisture damage in time.

Common signs of damage caused by moisture:

  1. Visible changes to floors (such as swollen floorboards), walls, facades or roofs
  2. colour changes such as discolouration, rings and dark spots
  3. Stale odour in the space
  4. Visible mould spots: green, white or black
  5. Peeling paint or bubbling wallpaper
  6. Loose joints in tiles and clinkers
  7. Porous plasters

It is above all a stale odours spreading through the house and colour changes that can give you a first hint that something is wrong. It is important to address this quickly and get to the root of the problem.

Difference between water and moisture damage

It is important to distinguish between damage caused by water and moisture. Water damage is caused by liquid water, while moisture damage is caused by water in the vapour phase, i.e. humidity.

Water damage is often caused by broken water pipes, but also when sewers, washing machines or drains do not work properly. Damage caused by water can often be covered by your insurance company if it is not due to lack of supervision.

Moisture damage can be caused by changes in the weather and seasons, but also by the occupants and their lifestyle. Hot showers combined with poor ventilation is one example. Poor drainage and heating are two other causes. Renovation after moisture damage is not usually covered by your insurance company.

What to do if you suspect moisture damage?

To begin with, it is important to address the root problem. If there has been moisture damage, which may even have developed into mould growthIt is important to address this before starting preventive work. In a damp environment, mould can start growing within 24 to 48 hours. It is therefore important to repair any damage as soon as possible to prevent the problem from getting worse.

Try to find and stop the source of the damp and contact a plumber or damp technician. Also document the damage and contact your insurance company. Once the damage is repaired, you can start working preventively and proactively to avoid similar problems.

Preventive measures

Moisture damage can quickly become a serious problem, so it is important to be alert to any damage. By working preventively, you can easily avoid moisture causing damage that will lead to costly renovations.

  • Regular inspection - Especially of exposed spaces such as bathrooms, crawl spaces, cold attics and basements.
  • Improved ventilation - Good ventilation with air circulation is important to allow the space to 'breathe'. A FTX ventilation unit can also recycle heat and reduce electricity costs.
  • Maintenance of sensitive areas - It is important to check that the roof is not leaking and that the drainage is in good condition.
  • Wipe up visible water - Clean up water spillages or drips from appliances.
  • Use a desiccant dehumidifier - Place an Acetec desiccant dehumidifier in humid spaces to dehumidify the air.

Using a desiccant dehumidifiers from Acetec is ideal for preventing high relative humidity, especially in cold and damp environments. The dehumidifier effectively absorbs moisture, which prevents mould, rot and bad odours from getting the right conditions.

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