How to Spot the Signs of Failed Cavity Wall Insulation
Heat loss in a building can be very damaging in terms of energy efficiency and the related costs, and cavity wall insulation is one solution to help reduce heat loss. The suitability of a building for having cavity wall insulation installed is not straightforward, however, and whether you are a homeowner, landlord or property professional, understanding the signs of failed cavity wall insulation is important.
An effective installation of cavity wall insulation in the right type of property should last over 20 years, but there are various factors which, when combined, can lead to it failing much sooner than that. This doesn’t just result in the building experiencing heat loss, it can also lead to much deeper problems such as structural problems, deterioration and health issues. It is therefore essential that you identify the signs of failing cavity wall insulation early.
In our experience carrying out property inspections, these issues are often identified before more serious damage and consequently, unnecessary expenditure, occurs.
Warning signs of failed cavity wall insulation
The reasons why cavity wall insulation fails are varied, and we will look at these shortly, but first, some common signs identified during property inspections include:
Cold patches – Damp and moisture generate a cold feeling on plastered walls, so if a patch on a wall feels cold when it didn’t before, the cavity wall insulation may have stopped working.
Damp patches – If water gets into the cavity in your wall the insulation actually helps it break through into your wall, and you may see damp patches where moisture appears. This is more likely to be at a lower level near the ground and is a common issue identified in properties affected by disrepair.
Mould growth - In a more extreme case the damp patches mentioned above may develop into black mould spots which are more visible. This is common where a room gets very warm and humid (such as a bathroom or kitchen) and can lead to health problems for people using the room.
Condensation – It is common to find condensation on your windows during winter, but if your cavity wall insulation has failed you may also see this on your walls, particularly if they are external walls. This happens when the cold air from outside meets the warm air of the building, because there is no insulation as a barrier to stop it.
Peeling paint and wallpaper – All the above symptoms can also lead to paint and wallpaper degrading, and hence this is a clear sign of a moisture problem.
Bigger energy bills – You may find that energy bills start to increase and yet you aren’t changing your usage patterns. This could be because heat is escaping through a failed cavity wall insulation and you are therefore using more energy to make up for this.
Unpleasant smell – If insulation gets damp it can start to smell and this is a deep, musty smell that penetrates a number of items and surfaces and is hard to disguise and get rid of.
Structural damage – Perhaps the most extreme symptom of cavity wall insulation failing is structural damage, i.e. where the plasterwork has weakened significantly due to moisture and the wall structure cracks. In reality, you should be able to identify the insulation failing much earlier to prevent this kind of damage occurring.
Why does cavity wall insulation fail?
There are numerous reasons why cavity wall insulation fails, many of which are commonly identified during professional inspections and investigations. These include:
The insulation gets damp – This is perhaps the most common cause, and this can happen through cracks in brickwork, mortar or render, and even blocked gutters. Once the insulation gets wet it is ineffective and very hard to get dry again.
Poor quality installation – Installation issues can include the cavity not being filled properly leading to gaps and voids where cold air can penetrate your walls, or the wrong material is used.
Ventilation issues – Walls need ventilation to help air flow through them and this needs to be considered and included with the installation of the cavity wall insulation. If this ventilation is blocked or wasn’t included, moisture will build up in the cavity and will eventually penetrate the walls.
Wrong insulation material – A property needs insulating material that is suitable for the location, such as whether the building is exposed and likely to meet high levels of wind-driven rainfall. Some types of insulation can fail more quickly when exposed to certain weather conditions.
Age of the property – If a property had insulation installed a long time ago, i.e. over 20 years ago, this may now have degraded and be ineffective. Some properties may have had cavity wall insulation installed in the 1970s or 80s, which has not been replaced, and is unlikely to still be effective. Some older properties may also be poorly maintained or have pre-existing damp issues caused by something else, which again, doesn’t help with heat loss and keeping cavity wall insulation dry and effective.
How Redfearn Experts can help with your cavity wall insulation
Professional inspection teams with vast experience of different properties are able to quickly identify problems with cavity wall insulation, and what may have caused them. At Redfearn Experts we have a team of nationwide surveyors who can assess your property and produce professional expert witness reports to provide important independent assessments, and valuable evidence in legal disputes. If you’re experiencing these issues, our surveyors can provide a detailed assessment to identify the cause and advise on the appropriate next steps. Contact our team today.
