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For the Heritage Open Days event last weekend I visited a SuperHome owner of a retrofitted Victorian semi.


As a climate research scientist Jonathan Gregory is, by his own admission, motivated to reduce CO2 emissions to mitigate climate change. For a ‘SuperHome’ the building must have a 60% saving in CO2 emissions as a result of changes implemented. This 1873 house was assessed in 2012 and had made a 64% reduction in CO2 emissions since ownership in 1998.

Jonathan has retrofitted over the years, gradually improving the performance of different parts of the home in different ways. In monitoring energy use since 1998 large ‘step change’ reductions have been attributed to specific improvements.

The rooms have been renovated to suit user priority, budget, space usage and relative inconvenience of the works. The semi sports a range of retrofitted energy-saving mechanisms, including a 5kW wood burning stove, double glazed sash windows, internal wall and loft insulation, solar thermal panels and photovoltaic panels.

But for my money the most striking measure is the external wall insulation to the large gable end. External wall insulation has been stalking its way around the country in the guise of a rendered wall ‘system’. Sales personnel have probably knocked on your door – as they have mine – and done a hard sell on its attributes, mumbling something about ‘Green Deal’ at the same time. Often the insulated render has clunky details – for instance render is cut around pipes that need access, essentially creating inconsistent insulation and associated cold (and damp) spots.

Admirably Jonathan opted for a more sensitive approach given the conservation area location: the Flemish bond gable wall elevation was extended by 310mm – 200mm of insulation and 110mm brick width (imperial sized bricks to match the existing).

Yes the roof was extended as well with matching eaves and verge:

New gable elevation

New gable elevation

yes the brick is beautifully coursed-in:

Flemish bond in imperial bricks recreated

Flemish bond in imperial bricks recreated

yes the gable window was recreated faithfully:

Internal view of newly created deep window reveals

Internal view of newly created deep window reveals

and yes the ground conditions were such that a steel beam the length of the wall was required to be installed upon which the brickwork was built off!

Jonathan estimates that at a cost of £20,000 this intervention has a payback period of 100 years at current energy prices. The effect of the gable wall insulation on energy usage is evident in the chart below between 2010 and 2011.

Graph of annual energy use

Graph of annual energy use

Jonathan is a true custodian of the built environment: he has unselfishly made a real contribution to the longterm future while remaining true to the building’s cultural roots.

Although the building is not listed this sensitivity recognises there is cultural value in large swathes of our existing building stock that this generation may be taking for granted. Equally it throws into focus the common argument of things being ‘not cost effective’. What will our generation’s legacy be? After this visit to a true ‘Super Home’ I am optimistic the bigger picture is starting to mean something.

The full case study which includes U-value information for this property can be accessed here on the SuperHomes website.

For more information on the SuperHomes scheme click here.