Insulation

The realistic optimist

By Albert Cardona, October 8th, 2022.

Inner city landscapes across the United Kingdom are punctuated by the ever present chimneys atop Edwardian- and Victorian-era houses. Careful attention to any such chimney will reveal not one but multiple flutes clustered together: inside the house, every room has its own coal-burning fireplace. While coal burning has long fallen to the way side and fireplaces have become often sought-after decorative epochal decor, there's another, more insidious legacy from those times, with impacts across the board from every day life to geopolitics: insulation. Or lack of.

According to the UK office of National Statistics (ONS), the median UK home had, in 2021, an energy efficiency score of band D: quite poor [1]. This means that half of the 27.8 million households (2020) in the UK have poor to very poor insulation. Single-glass window panes, 8-inch brick walls without a cavity, and--from personal experience with refurbishing a home in the UK--even when some insulation was added to home extensions, there are gaps, and the strong cold air drafts negate any benefits.

The median UK home is cold in winter and hot in summer. In Southern England, where most of the population lives, winters aren't ever very cold (almost never reach freezing temperatures) and, at least until recently, summers weren't very hot. This past summer, temperatures in the South of the UK reached 40C and the population was reportedly in agony. In the South of Europe, where I'm from, such temperatures are commonplace every summer for as long as we can remember. But houses and families are ready for them, both structurally and culturally.

My grandma's house, in a small village inland Catalonia, was built in 1808. The walls are thick enough that the window ledges, both inside and outside, are broad enough to place potted plants on them. In winter, some amount of short-term heating in the evening carries well into the night--although all be said, I remember the bedrooms as rather cold places; we used very fluffy blankets. In summer, when it's hot and dry outside, indoors the air is cool. A core memory of mine revolves around crossing the door lintel in the mid afternoon after playing outdoors in the heat, and being welcomed by a cool living room. Throughout the Mediterranean, families open the windows at night to let the colder air in, and close them in the morning to keep the heat out, thanks to proper, sensible insulation. Managing window shutters throughout the day for heat control as the sun moves from East to West is a daily summer routine.

The mild climate of most of England has masked the neglect in home refurbishment necessary to bring homes up to sensible modern standards. There's even a political campaign, Insulate Britain, to bring attention to the problem. That's how massive it is.

What would it take, what's the short term cost, of insulating all houses with low energy ratings in the UK? The upfront cost seems steep, but it isn't for an economy as large as the UK's. Assuming a high, inflation-ballooned cost of £20,000 to insulate a home, for the lower third of terribly insulated homes (about 9 million), the costs adds up to a total of £180 billion. For comparison, consider that the UK government lost many billions merely from the mismanagement of personal protective equipment (PPE) during the COVID pandemic, more from COVID relief fraud, and even more from a failed test and trace program, from poor planing and plain corruption. For an economy like the UK, £180 billion are small potatoes.

What would such an investment, £180 billion to insulate 9 million homes, bring to the UK? In the first place, enormous political clout to the party that pulls this off. Would be seen as modern, as serving the people, and having accomplished an extraordinary feat. Second, given that 80% [2] of all UK households heat up their homes with gas, such a move would drastically reduce not just heating costs for the lowest income families, but also the need for gas in the first place. With strong consequences for climate change (drastic reductions in CO2 emissions, both from avoiding to burning gas in the first place but also from reducing demand on fracking, which is disastrous for human health [3] and for nature and destroys natural carbon sinks), for people's budgets (drastic reductions in energy costs), and in geopolitics (drastic reduction of dependence on foreign countries). Only gas companies would be displeased, as their sales would plummet. Given that gas companies fuel political policy to favour them, there's going to be push back.

I am an optimist. Insulating the lower third of poorly insulated houses seems like such a low hanging fruit, so juicy at the hands of a professional politician, that it cannot not happen. Will "create jobs", "help working families", and similarly trigger a dozen of related slogans while actually delivering on its promises, for change, and positively impacting millions of people directly and the rest of us indirectly by mitigating climate change and geopolitical tensions.

To top it off, I'd ask for another £144 billion in investment: to procure 9 million heat source pumps (at £10,000 each) and install 2 kWh worth of solar panels per home (at £6,000 each, without batteries). This would free 9 million homes from having to burn any gas, ever, while also placing them off the grid for most of the day, alleviating pressure on centralized electricity production [4] and the power distribution networks. And all the same side consequences and political gains apply just as for the insulation project. What's not to like.

Come on, UK, we are rooting for you. Get yourself up and running and get this done. We know you can, and we know you would emerge thoroughly transformed.



  1. Band A is top quality, band F is very poor; see Home Energy Rating. Newly constructed houses aim for band A or B. That most UK houses are nowhere even close is a tragedy, brought about by political neglect and also reflecting the enormous income, wealth and health inequalities in the UK, one of the most unequal countries in Europe. See the Financial Times series on UK inequality. And "In Britain, the rich are richer but the poor far poorer than in Europe", and how "The UK is shown to be far more like the USA than other EU countries" (Dorling, 2015, Applied Geography). And "Compared to other developed countries the UK has a very unequal distribution of income", commentary on OECD data on Gini coefficients to measure income inequality at the Equality Trust. The ONS says that "Income inequality remains close to record highs over the 10-year period leading up to FYE 2020".
  2. "almost eight in 10 dwellings used mains gas as a main fuel source for central heating". See the ONS report Energy efficiency of housing in England and Wales: 2021.
  3. Except some have had the gall to state that fracking is less bad than burning coal is for human health. While true, fracking cooks the landscape and destroys rivers, water tables, soil, forests, and the livelihoods of plants, animals and humans nearby, leaving behind a scorched Earth landscape. The point is to stop fossil fuels altogether quickly, and insulation is a step towards that goal, not burning a different, less awful fossil fuel.
  4. Reducing demand on centralized electricity production would have enormous knock on effects. Would allow closing coal-burning plants. Would enable renewable energy plants to grow more slowly and therefore wisely. Would reduce pressure on country-wide infrastructure. All of these would reduce public spending across the board, freeing up resources for other projects, like education and health care.