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Extreme refurbishment
From Building for a Future Autumn 2003

Creating a low carbon economy calls for a 60% reduction in carbon dioxide emissions. If we are serious about this reduction, then the energy performance of houses throughout the UK will need to be significantly improved. Refurbishment will need to go beyond cavity wall insulation, double glazing and a condensing boiler.

A government-funded project to look at the practical issues involved with meeting these demanding levels of energy efficiency has just begun. The project aims to identify examples of 'extreme' refurbishment and learn lessons from those who have practical experience. The project was being co-ordinated by John Willoughby. A few years ago John, together with David Olivier, carried out a review of 'Ultra low energy homes in the UK'. This gave details of about 70 state-of-the-art newbuild projects. John hopes that this project will give corresponding examples of extremely energy efficient refurbishments.

One good example of 'extreme' refurbishment is the Ecohome in Nottingham. Here Penny Poyzer and Gil Schalom are refurbishing a three storey semi-detached house and are incorporating 24 'eco' features (see below) (1). These include: 300/400 mm of roof insulation, 150mm external wall insulation, solar water heating, heat recovery ventilators, rainwater recycling, a composting toilet and a biomass boiler. 'If we are serious about the future, we need to find and learn from other examples' says John 'Hopefully we will find a few examples of refurbishments that meet the high standards set by the Nottingham Ecohome. But we are also looking for examples of improvements to single elements. For instance wall insulation incorporating 75mm or more of insulation, 300 mm insulation to a sloping ceiling, advanced heat recovery ventilation in a retrofit situation and so on' (see table).

Another nugget from the White Paper is the fact that by 2020 we could be dependent on imported energy for three quarters of our total primary energy needs. At this point it is likely that fuel prices and shortages of supply will make extreme refurbishment much more attractive to the householder. We need to learn what to do now so that we are prepared for the future.

Criteria for 'extreme' refurbishment case studies
It is difficult to be precise about the criteria but these are the sorts of levels we hope to study. Obviously we wouldn't be particularly interested in a loft with 300mm of insulation but a pitched ceiling/roof with 200 mm might be interesting if it used spaced rafters or some other interesting refurbishment technique.

Ecohouse features at a glance
1 Flat-plate solar collectors for heating water
2 Roof insulation 300/400mm thick, made of shredded surplus newspapers
3 Roof lights with insulating (low emmissiity) glass
4 Natural plasters - clay and lime based
5 Super-insulated hot water tank
6 100mm ozone friendly drylining to front face to maintain exterior brick appearance
7 150mm exterior wall insulation with rendered finish
8 Space saving bath and thermostatic shower controls can save water
9 Heat recovering fans limit ventilation heat loss
10 Environmetally friendly paints

11 Draught lobby in porch
12 Triple- and double-glazed timber windows treated with natural fungicides and stains
13 Energy efficient appliances
14 Second hand, natural and reclaimed furniture
15 Stripped floorboards
16 Copper rainwater goods with filter for rain harvesting
17 160mm natural floor insulation
18 Rainwater storage for use in WCs, washing machine and outside tap
19 Low-flush WCs
20 Non PVC waste pipes
21 Composting chamber for solid waste from WCs
22 Separator lets liquids drain off and solids into composting chamber
23 Decking from English green Oak provides longevity without toxic pressure treatment
24 Organic land management utilising the principles of permaculture. Growing our own food saves on packaging and transport.

Author: John Willoughby

refs:
1. http://www.msarch.co.uk/ecohome/feature.html