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‘Green’ drive leaves thousands of families stranded in homes riddled with damp and mould

November 11, 2018

By Paul Homewood


h/t Patsy Lacey



Families are stranded in damp and mouldy properties because of a state-backed green energy scheme.

Thousands of low-income households were offered free insulation, double glazing and a boiler in a drive to cut greenhouse gases.

But contractors bodged the work so badly that sodden walls are sprouting mushrooms. The builders have now gone bust, putting ministers under pressure to pay for repairs to the 387 homes in Preston.

Campaigners fear that as many as a million homes renovated under the ‘Green Deal’ might be affected.

Residents in Preston’s Fishwick estate were offered the work by door-to-door salesmen employed by the big energy companies, which were under pressure to meet energy efficiency targets.

In 2013 entire rows of terraced houses were swathed in several inches of polystyrene insulation topped with pebble-dash rendering.

Occupants were soon complaining of severe damp in their front rooms and surveyors said the work had been bungled. Rainwater was seeping in through gaps before becoming trapped in the brickwork.

Some owners have been quoted £40,000 to repair the damage to homes worth £90,000.

In 2014, the company behind the main insulation scheme, InterGen, was ordered by energy regulator Ofgem to repair 62 homes at a cost of around £1.5million. But in a statement yesterday, Ofgem conceded it had ‘since become apparent that the problems with the work are more widespread’.

‘Unfortunately at the time of our settlement with InterGen, we were only aware of problems with 62 houses – so the agreed settlement with InterGen only required them to resolve these complaints and did not include any further issues that might arise,’ it said. It said it was ‘still looking at other options’ to assist Preston residents whose homes had been blighted.

Preston council, which has been working to help residents despite, it says, having no legal liability, said it had exhausted all avenues and only the Government could help.

Sir Mark Hendrick, who is the city’s Labour MP, highlighted the issue during an adjournment debate in the House of Commons last month. He said it ‘had been an absolute tragedy for those living in those 387 houses, who have been trying to put up with substandard housing and great inconvenience’.

In response, energy minister Claire Perry branded the saga evidence of a ‘strong failure’ by the Labour government which introduced the Green Deal. She promised to work on a solution.

More than eight million homes have been insulated over the past 20 years under a range of government-backed schemes to cut carbon emissions and reduce bills. Many have had cavity wall insulation retrofitted, rather than externally as was done in Fishwick.

But experts last year warned as many as 1.5million of these properties had been blighted by botched work, causing dampness and crumbling plaster. The insulation industry body said this claim was ‘wildly inaccurate’.

A spokesman for the Government, which scrapped the Green Deal in 2015, said: ‘Energy-efficiency measures, including insulation, need to be installed to a high standard for the benefits to be realised, including cheaper energy bills and warmer homes.’

The spokesman said ministers had brought in a new quality mark and a requirement for guarantees to be provided.



It appears however that the problem is not a simple one of cowboy contractors. Jeff Howells, the Telegraph’s property columnist has been writing about the issue for years. Below is a piece he wrote in 2015:



It’s not often that this column’s influence extends as far as Parliament. But an issue that I have been warning readers about for many years – cavity wall insulation (CWI) – was debated at some length at Westminster last week.

I cannot claim full responsibility for this. All I really did was introduce to each other three Telegraph readers – Pauline Sanders, Claire Eades and Dianna Goodwin (who featured in this column last October) – whose homes had become damp and mouldy following the injection of insulation material into their cavity walls.

Together, these three formidable ladies formed the Cavity Wall Insulation Victims Alliance (CWIVA) and have been lobbying the insulation industry, trading standards departments and their MPs to try to get justice for the many people whose homes have been blighted by this ill-advised practice.

His article is long and quite technical, but this section seems to sum up the root of the problem:

The industry and the Department of Energy and Climate Change claim repeatedly that CWI is almost always successful, and that only a tiny proportion of installations go wrong. They have no way of knowing this, because there has never been any follow-up testing.

I believe CWI problems are vastly under-reported, and that many more will come to light in the coming years.

Most dampness problems do not show up in the first few weeks following installation – they become apparent after two or three winters, or even longer. Some customers will have dampness and condensation problems that they do not realise are caused by the CWI, and will therefore not have reported them to anyone.

Others have not noticed any physical symptoms, but neither have they seen the promised reductions in their fuel bills (this is because wet insulation does not prevent heat loss, and can even draw heat out of a house, in the same way that a damp sweater makes you colder than no sweater). And there are many CWI victims who have reported problems to their installers and to CIGA – sometimes repeatedly – and simply never received a response.

What is needed is long-term monitoring of walls that have been filled, by taking samples of insulation from the cavities and measuring their moisture contents.

It is not true that only “unsuitable” walls can suffer from damp cavity insulation. As a former bricklayer, I know that no wall has ever been built well enough to withstand wind-driven rain. That is the whole point of the cavity – to stop rainwater crossing to the inside.

Moreover, even in sheltered areas, retrofit CWI is likely to cause problems, because its installation is contrary to the basic scientific principles governing thermal insulation.

Thermal insulation in dwellings requires a vapour barrier to be fitted on the “warm” side of the insulation, to stop moisture-bearing air from inside the dwelling finding its way through to the “cold” side and condensing out as liquid water.

Retro-fit CWI cannot allow for the fitting of a vapour barrier. Therefore it must result in interstitial condensation in the depth of the wall. Retro-fit CWI is a scientifically unsound idea.

Some six million UK homes have had retrofit CWI, and a large number of these are likely to suffer associated dampness problems at some time in the future. It is possible that the mis-selling of CWI will come to rival the Endowment-selling scandal, or even Payment Protection Insurance.

It is the whole principle of retrofit CWI that is fundamentally flawed, if Jeff Howell is right, and not just a few rogue contractors.

Not for the first time it seems, successive governments’ obsession with their green agenda might be causing more problems than it is supposed to solve.

  1. A C Osborn permalink
    November 11, 2018 7:02 pm

    My house (walls insulated in 1997) has not had any real problems, but my Son’s slightly older house (insulated about 15 years ago) has got major problems.
    The other selling scandal is Combi Condensing Boilers,their savings are way over hyped and they are no where near as reliable as the older simpler boilers.
    My first one was a disaster.

    • Mike Jackson permalink
      November 11, 2018 7:44 pm

      A very good plumber friend of mine was touting for business in the lead-up to the deadline for banning the old boilers some years ago. As he said, there is nothing to go wrong with an old-fashioned boiler. It’s nothing but a cast-iron kettle with a thermostat to control the gas supply.

      Most of his call-out business at the time was to combi-boilers. None of it to traditional boilers.

      • HotScot permalink
        November 11, 2018 10:06 pm

        My boiler is around 50 years old. Works like a charm.

    • Ian permalink
      November 12, 2018 8:23 am

      I’ve also had a good experience with (rock wool) cavity insulation but this is a bit of a lottery. I know of an example where severe problems occurred because of, it turned out, careless bricklaying, where surplus mortar was allowed to lie on the wall ties and bridge across. It doesn’t appear to be an issue if the cavity is retained.

  2. BLACK PEARL permalink
    November 11, 2018 7:04 pm

    Would you buy a house with the cavities that have been filled with spray in foam, rock wool etc …. not me
    Had plenty knocks on the door at it height of Govt subsidies
    None of them had thermal cameras to ‘after test’ for non insulated areas where damp & mould could flourish.
    All offering guarantees for decades etc that in the end mean nothing
    Its free the govt pays…… gullibility knows no bounds …
    Hah been waiting for reports such as this
    Son in law got his done FREE and his attic was dripping in condensation
    Had to get loads of extra ventilation vents fitted in the loft to alleviate the problem.
    So who’s going to bail out all these currently affected homes and those still to materialise in the coming years ?
    Insurance companies will be moving to another planet on this one.

  3. November 11, 2018 7:38 pm

    This is due, primarily to the muddled technical thinking of the Greenblob, which has perminated the thinking in government departments attempting to find a solution. – Departments totally unable to appreciate the experience over the years when dealing with the obiquitous nature of water and it’s thermodynamic properties.

    Solutions arrive, bottom up; not by throwing money at it.

    This is a good example of duff education generating problems. – Right across the board.

  4. Joe Public permalink
    November 11, 2018 7:38 pm

    Not mentioned, but contributing to the consequence is ‘improving’ the air-tightness of homes.

    Cutting draughts reduces heating bills, eh? It reduces the quantity of that expensively heated air being lost to outside to keep the birds warm (i.e actually contributes to global warming!)

    But insufficient ventilation can lead directly to damp, and mould growth. After all, we exhale significant quantities of water vapour.

    At the opposite end of the scale are Victorian homes with solid walls, and fireplace & chimney in many rooms.

    Those fireplaces created high air-infiltration rates that introduced massive amounts of (cold) fresh air, that then had to be expensively heated. But they suffered relatively little damp mould.

    Occupiers of homes with double glazing really, really ought to ensure that a number of the ‘trickle’ vents are left permanently open. Certainly in the kitchen & bathroom; and, in bedrooms too.

    • November 11, 2018 7:51 pm

      I always ensure an air flow via my woodburner chimney when it is not in use. I also have three expelairs, a cooker hood vent, a vent at the back of the tumble drier and two unsealed letter boxes, all of which allow a permanent air flow from inside to outside (and vice versa).

    • HotScot permalink
      November 11, 2018 10:37 pm

      Joe Public

      This is, of course, what the government didn’t consider before the insulation scam. Because they didn’t bother to talk to a decent builder, they relied on laboratory studies based on idealogical theories of insulation and forgot humans in the equation.

      Almost every house built in the UK relies on external ventilation and air exchange via ‘draughty’ windows and doors, fireplaces lit during the winter months to draw air through the house in Victorian buildings, frequently a fireplace per room. Actually, well designed concepts for the era.

      Now we have ‘super’ insulated new houses with precious little ventilation and fake fireplaces, so no air exchange but still designed to Victorian designs. It is utterly ludicrous!

      The only way that can be effectively addressed is by retro fitting heat exchangers to almost every room, but especially the multiple bathrooms everyone demands. This is vital if solid wall Victorian buildings are double glazed and, as is normal, the fireplaces sealed off.

      Wood burning stoves are little better as the heat they produce is far higher than the temperature outside and no matter the depth of insulation, eventually cold air will meet warm air which condensates unless ventilated.

      House building is easy when the fundamentals of ventilation are adhered to. The tough bit is to make people understand that insulated houses come at the price of ventilation. Either the heat is exchanged with the outside air directly, which is costly or it’s processed via heat exchangers, which are also costly.

      The cost of living in a hygienic, well ventilated, warm, free standing building is high. But governments don’t want to admit that so they encourage shoddy housebuilding to satisfy the demand they don’t want to pay for.

      I have been researching building my own house for several years now. Man, it’s tough. I want one for my retirement that is cheap and easy to run; a simple expectation, but a monumental task.

  5. November 11, 2018 7:45 pm

    This is just another example of the result of central planning by incompetent politicians and their incompetent civil servants and advisers. It is a fine example of the law of unintended consequences – all the potential consequences should be examined in detail before going ahead with any new scheme.

    After I had the (then) latest thickness of loft insulation installed I had to go round and insert lots of soffit vents to eliminate condensation problems in the loft. I make regular checks to see that there is adequate ventilation.

  6. Athelstan permalink
    November 11, 2018 8:13 pm

    I hoped that, this would never come to pass, our Australian cousins had similar even deadly experiences of the ‘green deal’ and the lessons will never be learned by our less than useless administration – I can’t call it a government.


    Many public servants have faced a barrage of questions about how the scheme was formulated and if they knew about the risks, especially given that a similar scheme in New Zealand in 2007 had led to the deaths of installers.

    So far some of the most controversial evidence presented to the commission revolves around allegations that public servants pressed ahead with the scheme after being alerted to these safety concerns.

    God forbid it but what are the chances of this unhappy circumstance occurring- in the UK?

    imo, home insulation is a pretty good idea but only if the house can ‘breath’, all else is political ‘targets and box ticking’ which could endanger not only bodging fitters but your good health……………yet; do they care a fig – HMG couldn’t careless.

    • Dave Ward permalink
      November 11, 2018 8:50 pm

      It’s not just “Us” and Australia – I’m sure I remember Pierre Gosselin reporting on exactly the same condensation problems whith additional insulation fitted to lots of German homes. I can’t find the specific post(s), but the comments here mention the problems:

      • Sheri permalink
        November 11, 2018 11:36 pm

        Again, this is quite fascinating. In America, most homes have insulation. After 1980, it was required. I can’t imagine living in an uninsulated home. Of course, I’ve always lived where the temperature could reach -30F and now where the temperatures are equally low and the wind up to 40 or 50 mph. Without insulation, the house could not be heated.

        I do have trouble with windows getting wet when the temperature is really low at night. I have sealed windows, but need to improve the method next summer. While I fully understand why a home needs ventilation (and mine has plenty), the lack of insulation is just not something I’ve seen. Far southern states in the US may have none, I’m not sure.

      • JerryC permalink
        November 12, 2018 12:40 am

        I used to live in an uninsulated house (built in 1917) in Tacoma, WA. Weather there is fairly similar to northern Europe and the UK. We looked into getting insulation blown in, but the possibility of condensation was a known issue so we thought better of it and just paid the gas bill.

  7. November 11, 2018 11:13 pm

    An American perspective. I owned until earlier this year a largish Wisonsin dairy from 1985 til mid this year. The central two story farmhouse were the original log cabin from oak squared, beaver tailed hand hewn logs. We were gifted a ~1890 picture of those original pioneers. And I collected a full set of the handle tools those pioneers used to build what became my families all season get away.
    No way would any of the ‘green’ solutions have ever worked there then or now. We got summer Tstorms that would topple wind turbines, we got winter minus 20 with snow that would fully cripple PV.
    When the pioneer cabin was built they relied on horses, hay, and firewood. My family relied on diesel (horse tractor replacement), gas (bucksaw chainsaw replacement), and electricity—albeit frequently out, for which we had kerosene lamps and a newish (I put it in summer of 99) handpump well just outside the present kitchen.
    Nobody could have or would ever now survive there on renewables alone

  8. John F. Hultquist permalink
    November 12, 2018 3:56 am

    Inside air quality seems to have been lost in this.
    In addition to mold and breathing, modern households often use chemical cleaners, and materials themselves frequently give off vapors. Issues are known such that gadgets designed to test the air are available, say on Amazon dot com. Search for indoor air quality monitor.
    In winter season, when folks close up the house, they may be breathing very poor air.

    • Sheri permalink
      November 12, 2018 1:52 pm

      It doesn’t have to be. You can insulate and still have a house that breathes. As far as modern cleaners, you are not mandated to use those either. You can use vinegar, soap and water. That’s basically all I use, since I react to many different cleaning products. Poor air can be avoided by lifestyle, it does not require skipping insulation.

      Yes, I do understand that sealed houses are a bad idea. But insulation does NOT seal a house. There’s far more to it than that. Windows, doors, attic vents, etc. all affect air exchange in a house.

  9. paul weldon permalink
    November 12, 2018 9:22 am

    I don’t believe many people have a clue as to how porous most bricks are: I remember viewing the inside of a brick-built garage after a day of heavy rain and driving wind. The water was running down the inside of the walls. There is in fact a simple cure that works in most cases – a transparent silicon liquid that is easily painted on the outside of the wall, thus sealing the brick and stopping most of the water from entering. As far as I am aware, the bricks can still ‘breathe’ which is important. This is going back some 30 years, so no idea under what tradename the liquid is sold. I found out as I used to erect conservatories and when they were put over windows, there were occasionally problems with ‘leaks’ to the ridge area. My work was OK so obviously something else was happening. It was in fact the flashing in the house brickwork over the windows, whereas before this was taking the water to the outside, with the conservatory it became ‘inside’. Worth a try?

  10. Vernon E permalink
    November 12, 2018 12:17 pm

    What a horrible muddle. The Mail piece seems to refer to a very localised problem with some exterior plastic cladding – probably solvable by removal. Jeff Howell’s (God bless him) work refers, and always has done, to injected insulation which is more common. My old house was so insulated before I bought it and its fantastic – never lived anywhere so snug, cheap to heat and no dampness whatsoever. However, when I have investigated for other family members with similar properties the contractors invariably refuse to do the work because the building regs say that there must be two courses of bricks showing below the DPC – which is rarely the case in old properties. So, millions of potential benificaries lose out on these schemes. Surely its not beyond the imagination for the building and insulation industries, perhaps with a university, to come up with a solution for a non-damp-transmitting foam for the lowest levels.

  11. Sheri permalink
    November 12, 2018 1:20 pm

    I still find this fascinating. The blame is always put on the insulation, when in fact the insulation most likely made worse an already existing problem. Since people are really, really, really poor at understanding cause and effect, and hate the government, they blame the insulation. Case in point in my own home (not involving the government). I have a leak at the joint between my porch and home. It’s been there for decades. No amount of flashing, etc, stopped it. My husband’s non-carpenter roommate built it and did it poorly. I actually have a gutter piece to direct the drips (the catch bin doubles as a wolf spider trap!). A few years back, my husband had to repair the ridge cap of our shingles. Voila! No more drip!!! It was NOT the obvious that caused the drip. Now, with time and wind, the drip is back. It will only be repaired when we reroof. The most obvious was not the cause, but we spent years blaming the poor construction of the porch.

    New homes in the US all have vapor barriers in the walls before the insulation. Again, I rarely see any complaints about insulation and have never even considered living without it since my parents’ northern Iowa home accidentally had no insulation installed, snow came through to window frames and we spent hundreds on propane trying not to freeze. (They added blown in cellulose.)

    I suspect that poor installation, government hatred and lack of understanding of cause and effect have more to do with this than the actual act of insulating a house.

    • A C Osborn permalink
      November 12, 2018 8:38 pm

      And you would be wrong.

      • Sheri permalink
        November 13, 2018 2:33 am

        And you could provide reasons if you have any.

  12. paul weldon permalink
    November 12, 2018 5:10 pm

    I like this from Wiki:
    ‘ In the past 20 years the concentrations of nitric and sulfuric acid has decreased in presence of rainwater, which may be due to the significant increase in ammonium (most likely as ammonia from livestock production), which acts as a buffer in acid rain and raises the pH.’
    Seems like we should be eating more red meat!

  13. tom0mason permalink
    November 12, 2018 8:08 pm

    This is the result of engineering by Government bureaucratic mandate instead of proper engineering principles. Wasting tax-payers money on subsidizing the incompetent.
    Damp & mouldy residences? Government and council incompetence.
    Grenfell Towers and the many other buildings now deemed a fire risk? Government and council incompetence.

    Just like useless solar and windfarms, or the very evident incompetence of replacing/upgrading nuclear power stations. Wasting tax-payers money on subsidizing the incompetent. Government’s bureaucrats must get out of making engineering decisions as they are useless at it! Government must get back to governing and leave engineering to the engineers.

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