What to do when insulation gets wet?

 Water sustains life. Although it is vital to human health and wellbeing, it can harm your facilities. The high humidity levels, leaks, burst pipes all lead to condensation and other moisture-related issues causing moulds and other problems.

In this blog, we will explore why insulation materials should be kept away from water, how water impacts the insulating properties of the products, and much more. If breathable or water-resistant mineral wool or foil insulation is what you are looking for, we have just what you need at Buy Insulation Online

What makes insulation materials damp?

Insulation, as we know it, is used to limit the transfer of heat through building fabric. 

The daily, basic activities we do, like showering, cooking and others generate a lot of steam, which could get trapped within the building without proper ventilation. In addition, the building's insulation may not be breathable and could prevent the humidity from escaping via the walls or ceilings. When this happens, the moisture gets trapped in the insulation itself. There is also a possibility of dampness from the building materials like plaster being absorbed by the insulation materials, making it damp.

In fact, it's pretty simple. Warm air contains moisture. This moisture must go somewhere, right? So, when there is no outlet, it reaches its dew point and condenses, either on the insulation or the building material. So, it's critical that you have proper ventilation along with adequate insulation. 

It's annoying to have an attic full of mouldy boxes, seeing it affect your belongings and furniture after having had to spend quite a lot of money and time to make your home comfortable. 

Wet insulation: what are the effects?
1. R-value:

In simple terms, the R-value of insulation indicates how effective the material is at retaining heat within the structure. Insulation is better when the R-value is greater.

When your insulation becomes wet, the thermal performance (R-value) reduces as the water displaces the air trapped within the insulating material. It makes the insulation lose its insulating ability. It starts transmitting heat instead of blocking it. As a result, the insulation becomes ineffective, leading to an increase in energy bills. 

2. Mould growth and air quality:

Mould is known to thrive in humid conditions, and it seems to have a special place for the UK because of the wet weather and the frequent downpours. Moulds, once formed, are very difficult to be rid of. 

Moulds adversely affect the health of your family. They are known to cause respiratory disorders, allergies and even asthma. They give off an unpleasant, musty lingering smell that does not just make your indoors uncomfortable, but also reduce the air quality. 

3. Wet walls lead to overall structural damage:

You may not know if your insulation is wet or not, as it is rarely visible, typically found behind the walls or underneath the floor/roof. Bubbling wallpapers, visible brown coloured watermarks on the wall and peeling paints are often the first signs of wet insulation. When left to its own devices, moisture can cause structural damage in the longer run.

How do different insulation materials react to moisture?

Fibreglass Insulation: Even though fibreglass insulation is resistant and is generally unaffected by moisture, a burst pipe or leaking roof can make the insulation wet. When this happens, the water displaces the air spaces between the thin fibres, affecting its insulating ability. 

Proper ventilation in the area where fibreglass insulation is being laid or using vapour barriers can prevent moisture build-up within the insulation. 

Regular checks on the insulation can help catch the issue early. If the fibreglass insulation is found wet, remove the affected batts and place them in a warm place to dry out naturally. Once dried, you can install the fibreglass insulation back in place. Check the insulation again in a few days and replace it if the smell or moisture persists.

Mineral Wool Insulation: Mineral wool or rock wool insulation allows vapour to pass through. This moisture-resistant insulation does not wick water and since it is not made of any organic material, it does not promote mould growth. However, when there are leaks around the insulation, it may get wet. It will also regain its previous performance once it fully dries out.

PIR insulation: The foil facings on the PIR Insulation board makes the insulation water-resistant. If, however, the insulation becomes wet after continual exposure to high humidity, allow the moisture to evaporate naturally. Do not use any sort of heating source or naked flames to dry out the insulation.

After the PIR board has dried out naturally, it will regain its original insulating capacity. The closed-cell structure of the PIR insulation makes moisture absorption and drying out easy and less time-consuming. 

Damp after loft insulation:

If you have a cold loft space that is used for storage, chances are that when the heated air gets into this space, it condenses and creates vapours on the insulating material itself. Use water-resistant mineral wool insulation to insulate in between the joists. 

Damp in cavity wall insulation:

Cavity wall insulation does not cause dampness. It may, however, enhance the problem if moisture-related issues already persist. It is recommended to check for any such issues before you install cavity wall insulation

If the insulation was installed about 25 years ago when things were not as advanced as they are today, or if the wall insulation is incorrectly installed, it may cause condensation within the insulating material. 

Moisture can also enter the cavities when the external walls are moist, either by absorbing rainwater or because of poor brickwork. The insulation can get wet if there is much temperature difference between the outer and inner walls, causing the warm air to condense on the material itself.

You can trace these issues with the help of a professional and remedy them according to their suggestions.

In conclusion:

The use of moisture-resistant insulation along with proper ventilation helps win the battle against dampness and makes your home condensation free. In addition, check your insulation regularly and keep an eye out for pipe bursts or leaks that could cause moisture build-up. 

If you are looking for moisture-resistant mineral wool insulation for ducts, pipes, walls or lofts, or if you want to replace your existing loft or walls insulation, we at Buy Insulation Online can help you. Get 5% off on your first order with us and plant a tree for free to offset your carbon. 


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