Loft and cavity wall insulation figures down

Figures have been released that show that the number of cavity wall and loft insulations in Great Britain is falling.

Cavity wall insulations in the last quarter fell from 128,000 to 95,000, a fall of 25%, and a staggering 45% below those installed in the same quarter last year.

Also, the number of professional loft installations fell by 32%, and is 38% below the number installed in the same quarter last year.

DECC has published the figures, which also show that at the start of July 2010:
• 12.3 million homes had loft insulation of at least 125mm
• 10.3 million homes had cavity wall insulation.

In Great Britain 23.2 million homes have lofts and 18.6 million have cavity walls. This means that 47% of eligible homes do not have sufficient loft insulation and 45% have no cavity wall insulation.

What the figures do not reveal is the level of effectiveness of the installations. Those which the author of this article has seen leave much to be required, i.e. gaps that mean that their ability to keep heat in is severely curtailed.

This implies that they cannot be relied upon to generate the carbon savings that will be assumed in government figures.

Moreover, the figure of 125mm for loft insulation is not sufficient. Current building regulations require a roof to have a thermal resistance U-value (a measure of their insulation value) of at least 0.13W/m2K, which would typically be achieved with 300mm of loft insulation.

DECC says that a threshold of 125mm is used in these statistics since homes with less than this would expect to see significant improvements in energy efficiency from a top-up.

It also says in its Departmental Business Plan 2011-15 that this measure will be one of its key impact indicators to track progress on insulating homes.

But if it really wants to show the scale of work required and monitor improvements, it should be using its own Building Regs figure of 300mm of loft insulation.

In addition, the width of cavities in walls varies considerably. Just because a wall has cavity insulation does not mean that it meets any building regulation requirements for thermal resistance of outer walls.

The figures are obtained via surveys from the English Housing Survey and equipment for Scotland, Wales and Northern Ireland.

Most of the statutory work has been carried out through the Carbon Emissions Reduction Target requirements. Only a small proportion has come from Warmfront, which targets the fuel poor. DIY loft insulation is currently done at around twice the rate of professional work.

The energy hierarchy

Last week the Low Carbon Kid attended a seminar at the Energy Saving Trust as he is one of about 30 'Green Ambassadors' for energy efficiency.

Its director Philip Sellwood (an unusual bloke, previously director of off-licence chains Threshers and Victoria Wine, and a Home Office advisor) was offloading all sorts of gripes about goverment attitudes to energy efficiency. Here are three titbits:

1. Does the EST support new nuclear power?

Not as such - but in practice it works out that it doesn't.

This is because the Trust argues that all means of both saving and generating energy should be looked at for cost-efficiency and ranked accordingly.

You then proceed up the hierarchy until you've met everyone's needs. They've worked out that everyone's needs would be met before there's a need for nuclear new build.

(This chimes with CAT's analysis - Zero Carbon Britain.)


So, given that investment in energy efficiency is always more cost-effective than building new generating capacity, this comes first.

Then comes microgeneration - solar water heating, heat pumps, water power, wind power, biofuels (wood boiler), solar electricity (in that order and if available).

Then we have combined heat and power - still on decentralised energy. Gas for electricity and heat supplied locally.

Then clean coal.

Then large scale renewables (wind farms), then tidal and other marine energies.

Finally nuclear power stations. The total life cycle costs - including looking after that waste for thousands of years - make this the least cost-effective.

Unsexy cavity filling

The most cost-effective energy efficiency measure if you have a cavity wall in your house is to fill it with insulation. It takes a day for a contractor and pays for itself in about nine months.

Despite this, millions of homes have yet to be treated and yet it would go a long way to reducing our carbon emissions.

Philip has tackled the Treasury several times on providing funds to support this.

Treasury bright boffins: "Obviously it's perfectly the rational and obvious thing to do, so people will do it."

Philip: "But people aren't rational. They prefer to spend money on sexier things."

Treasury: "Then they should be more rational. Sorry, we've got a military machine to support."

So lots of money and carbon continue to be wasted.

Non-eco schools

The government is committed to rebuilding every secondary school in the country. A massive undertaking.

Several schools are now eco schools and have solar panels and wind turbines to educate the pupils. This is, you would think, (rationally?) a perfect opportunity to make every school an eco-school.

Clearly, if we teach children energy efficiency, it's the best we can do for our energy future. And what better way than for the schools themselves to demonstrate what it means?

But Philip has found out that:

a) No energy-efficiency or renewable energy features are in the specifications for the buildings

b) He asked all government departments to cooperate with energy efficiency week next week - they all signed up to help out - except the Department for Education and Skills. It said it had too many messages already to get across to schools.

I wonder how Philip keeps from tearing down the walls with his fingernails. Perhaps he has a few bottles left over from Threshers to calm his nerves.