Insulation No Guarantee?

Using insulation to reduce energy costs must always be the first “port of call” and is unquestionably the best effective treatment and energy reduction measure in any property.

With new techniques, rigorously researched and proven modern materials and through experience, it’s probably as good as it gets at present.

The issue is: what has or is likely to happen to cavity wall and roofspace insulation materials over an extended period of time?

In the past few months, I’ve been working with an insulation manufacturer, Energystore, on behalf of 12 insulation companies to examine older treated properties and the resultant long term thermal protection of the same.

Digressing a bit – and to give a clear understanding of the industry’s economic importance – the UK market for home insulation has a turnover of around £700m per year and this is expected to grow with future household energy efficiency measures, such as Warm Homes, Green Deal in the UK, and so on.

So by any stretch of the imagination, insulation practice has a high importance in tackling energy loss, fuel poverty and CO2 reductions and has a major role in employing many people – approximately 16,000 in the UK.

Local insulation manufacturer Energystore has conducted detailed surveys (visual, endoscopic etc) mostly on aged, privately-purchased properties which has highlighted some serious issues with past treatments.

From the survey findings (initially 14 homes) many highlighted disturbing issues, the collapse of fibre in cavities (as much as a metre), breakdown of the insulation materials, damp, insulation voids and roof space issues.

The survey is a mirror image of the report completed by Kingspan, entitled “Injected Mineral Fibre Full Fill Cavity Wall Insulation, Workmanship, Voids and Heat Loss” which can be accessed online at the website www.insulateonline.com

In the report, Kingspan Insulation Ltd approached two local authorities for permission to carry out exploratory thermographic imaging of publicly-owned properties insulated with injected mineral fibre, full fill cavity wall insulation.

Thermographic investigations were followed up by endoscopic investigations of 20 of the 84 properties which involved drilling properties’ walls, through which an endoscope was passed to view the cavities.

Of the 84 properties surveyed, 34 showed patterns associated with missing or low density insulation. The presence of voids and low density insulation was confirmed by the endoscopic survey.

Amalgamating the heat losses caused by these defects gives the resulting summation of 1200 kWh of additional heat loss per year, equating to 344 kg CO2 emissions per year.

Finally, this could be regarded as costing occupiers of properties likewise insulated, £37.2 million per year in wasted fuel bills.

1200 kWh of heat lost i.e. N. Ireland fuel prices to replace:
• 120 litres of domestic heating oil, circa £72
• 1200 kWh electric circa £206 (E7 tariffs, standing charges, cheaper (usage dependent)
• Natural Gas (allowance for tariff regimes) circa £60

No one can afford energy losses on this scale and I believe there is a need to examine the nature of treatments in past years.

Assuming that the properties surveyed are representative of the wider UK housing stock poorly insulated in this way (maybe close to 4 million properties), the use of injected mineral fibre cavity wall insulation could be regarded as wasting the UK 1651 GWh (million kWh) of heat per year i.e. (a sizeable power station worth of energy per year).

In Northern Ireland the ‘Home Condition’ survey report sets out the level of insulated properties and details the number that still go untreated and other very relevant social and economic analysis information. The latest 2011 report sample was reduced from 3,000 properties in 2009 to approximately 2,000 (core circa 760,000 properties).

Therefore. if one was to assume that the sample selection process could be questioned (0.26% of the total) then maybe there are many inhabitants living in properties less energy efficient or healthy to live in as reported.

We have engaged with University of Ulster staff to discuss the findings and both educational partners feel that it’s important that an analytical understanding of long term insulation factors are identified and the results acted on if the pattern unfolds as per the initial findings.

This opens up a possible major chasm between real life and what’s reported, and must take into account the product and quality of treatment.

This issue needs to be addressed if steps to provide low energy cost living can be realised and truly guaranteed in terms of product and workmanship.

As the move to Zero carbon buildings becomes reality then there is a need for professional certified installers and training regimes to be put in place. From the information in the initial Energystore survey (and others conducted since) they reflect real and serious issues in some past home insulation treatments and it needs to be addressed in some form or other.

The re-filling of voids in injected fibre cavity wall insulation, where it can be done, is expensive and questionable, so it’s perhaps better that the contents are removed (evacuated) and refilled.

Repairs should be completed with the use of thermographic equipment to control the work and guarantee quality.

Can little be done to remedy any problems which may arise in low density injected mineral fibre cavity wall insulation other than replacement?

The 2011 home condition survey preliminary findings highlight some interesting facts:
• In 2011 there were an estimated 35,200 unfit dwellings in Northern Ireland, representing a rate of 4.6%
• This is similar to the unfitness rate as found ten years ago in 2001 (4.9%: 31,600)
• Unfitness declined between 2001 and 2009 reaching a low of 2.4% in 2009 (17,500 properties)

The 2011 HCS shows a small increase in unfitness which reflects the current economic environment, the higher rate of vacancy, particularly in the private sector, and the reduced availability of home improvement grants.

In light of what’s been discussed maybe it’s time for a serious rethink of what we spend capital funds on. In my view we really need a whole building approach to energy funding.

Clearly the chances are that if you live in an older dwelling your insulation is not guaranteed!