The UK insulation market is currently showing an increased trend for the removal/extraction of existing cavity wall insulation (CWI) in houses where it was fitted up to 25 years ago.
The two most common reasons for the removal is where the insulation has been poorly fitted or where an incorrect material was fitted in geographically exposed areas.
One such exposed area is South Wales, which has been classified as being severely exposed to rain and wind. Therefore, only certain products, such as polystyrene bead (EPS), should have been used.
However, because of the high demands for CWI during the last decade or so under schemes such as CERT, and to ensure that Government targets were met, most of these houses were insulated with any material regardless of its suitability for exposed areas.
We are now seeing the aftermath of this poorly controlled practice to those houses where it was fitted. Even more alarming is that flooding of areas within the UK in general is becoming more frequent and so exacerbating the problems.
Mineral fibre/wool provided a very economic and quick installation for many companies. When fitted as per the specifications it also serves a purpose within the industry. However, the end result i.e. the quality of the entire installation does rely very heavily on the individual on-site technician who must decide the density and amount installed for each property. And so it is imperative that the installer is properly trained and certified.
EPS removes this dilemma as the density is set at production stage and cannot be altered. EPS is also ideal for larger cavities or hard to fill cavities where EPS’s superior stability and flow characteristics avoids any collapse of insulation and ensures complete filling of the cavity. This provides for a more consistent on-site installation.
EPS is not adversely affected by moisture. However, mineral fibre/wool does retain moisture and therefore does adversely affect the performance of the product. Consequently, a lot of mineral fibre/wool being extracted is emerging soaking wet due to the unsuitability of this material for geographically exposed locations.
When that unsuitability of the material is judged alongside the risk of error and potential variations during installation, it is no surprise that so much mineral fibre/wool is being removed due to voids and damp.
More alarming within the industry is that whilst research and modern testing proves that EPS reacts more favourably to long-term, severe weather conditions, funding is being repeatedly cut and this is pushing some installation companies towards cheaper but less suitable fibre products, purely for economic reasons.
Consequently, lessons are not being learned and mistakes are being repeated. There are even instances of companies extracting defective and damp fibre and replacing it with yet more fibre.
The simple and only solution is to ensure that EVERY house has the correct product installed so that long term benefits can be enjoyed by all and the industry is serving the public to the best of its ability.
It is also of the greatest import that those requiring information regarding the suitability of any cavity wall insulation, be they Local Authorities, Housing Associations or private individuals, have access to all information, so they are enabled to make fully informed decisions based on the suitability of the various available materials.
More information can be found on the NBBA website, http://www.nbba.org.uk/