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Chris Mead and Jay Hayter are perfectly ordinary people. He鈥檚 a financial analyst and she鈥檚 an IT project manager, and neither of them had a clue about construction until recently. But this couple are key to the government鈥檚 ambition to cut carbon emissions from buildings. Why? They decided to sink their hard-earned cash into transforming their run-down, three-bedroom Victorian house in London鈥檚 Elephant & Castle into a very low energy home - the sort the government desperately needs more of if it is to hit its new target of reducing carbon emissions by 80% by 2050.

The government is at last acknowledging the key role the existing stock plays in reducing carbon emissions, and its recently published Heat and Energy Saving Strategy consultation calls for emissions from all buildings to be approaching zero by 2050, and all homes to have received a whole-house package of energy-saving measures by 2030. The reason Mead and Hayter are vitally important to the country鈥檚 energy-efficient future is that over 70% of homes in the UK are owner-occupied and getting those owners to improve their homes is the only way the government will hit its targets.

Like many home improvers, Mead and Hayter didn鈥檛 have the budget to pay for an army of professionals to work out the best way to make their home energy-efficient. And like most people, they wanted the end result to be easy to live with. 鈥淭he key thing we wanted to achieve was to upgrade the energy efficiency of the house without making too many sacrifices,鈥� says Mead. 鈥淲e didn鈥檛 want to be eco-warriors living in a homespun eco-house, rather we wanted it to be an eco-house that was suitable for 21st century living.鈥� Mead and Hayter鈥檚 experience holds valuable lessons for government and industry. So how did they manage?

First steps

The couple didn鈥檛 have any specific energy reduction targets in mind; they simply wanted to make the house as low energy as possible. As neither of them had any experience of eco-renovation, they had to start from scratch, although Hayter鈥檚 project management skills came in handy when it came to planning the job.

The first step was to research where to start. 鈥淚t was all new, like going back to school,鈥� says Hayter. The first hurdle was the lack of a single source of reliable information to help so the couple spent two months going to trade shows, trawling the internet for information and even making the pilgrimage up to the Centre for Alternative Technology in north Wales. 鈥淭here is no one place you can go to for practical advice for renovators to pull all this together and understand the differences between products and what the technologies are,鈥� sighs Mead.

Insulation

We wanted to upgrade the energy efficiency of the house without making too many sacrifices

Chris Mead

Armed with all the information they gathered, the couple were ready to start making decisions. They began by tackling the more obvious stuff, like insulation 鈥� they have used a high-performance, 65mm thick, phenolic foam-backed plasterboard to line the external walls of the building. This has been applied to the inside of the walls as the home is built from London stock bricks and external insulation would ruin the traditional appearance of the home. The insulation reduces the U-value of the walls from 2.5W/m2K down to a very respectable 0.35W/m2K. Mead sourced the insulation board from a salvage yard and paid just 拢15 for a 1.2m x 2.4m sheet rather than 拢60 for a new sheet. Internal insulation can affect traditional features like cornicing as it makes the walls thicker but this wasn鈥檛 a problem as most of the cornice in the home was missing apart from the dining room on the ground floor. The roof space was insulated with 270mm of sheep鈥檚 wool and a multifoil insulation product has been used where the roof dips down into the centre of the house where the central valley gutter is located.

Heating

The biggest decision faced by the couple was how to heat their home. After much debate they decided against a standard gas condensing boiler and went for an air source heat pump instead. 鈥淚t was one of the biggest changes we made,鈥� explains Hayter. 鈥淲e went to numerous trade shows and asked manufacturers about the pros and cons of boilers and heat pumps and went for the pump.鈥� It was a much more expensive choice; the heat pump is coupled with two solar thermal panels with a total cost of 拢9,000 rather than 拢3,000 for a gas boiler. But Mead and Hayter chose this system as its efficiency appealed to them 鈥� it extracts 2.9 units of heat for each unit of electricity needed to run the pump. The electricity can be provided from renewable energy via a green tariff, unlike fossil fuel gas, and the couple calculated it had an 11-year payback period. They also reckon the system will add value to the home.

The couple worked out how to make the system as efficient as possible themselves. Heating system configuration and outputs are normally handled by installers but Hayter and Mead felt they could do a better job. 鈥淚t鈥檚 the one area where we had to do the most research. We had to calculate our energy usage, as the system had to be optimised for our particular energy needs,鈥� explains Hayter. 鈥淭he installers have their own software but only we knew how we were going to use the house and didn鈥檛 want to rely on someone else鈥檚 view of how it should be set up.鈥� The heat pump has an output of 14kW and is coupled to low water content radiators. These have to be bigger than conventional radiators as the heat pump works more efficiently when the heating water is at a lower temperature than is produced by a conventional boiler. Ultimately, the couple want to install a wood burning stove in the living room to minimise use of the heating system.

Water

Cutting down water use was also a priority. Mead and Hayter wanted to install a rainwater harvesting tank under the rear garden but initially this didn鈥檛 seem possible. They made up a wooden frame to mimic the proportions of the 2,700 litre tank which is supplied in two halves but found it wouldn鈥檛 go through either the door or front window and even if they got it into the house they would not have been able to get it into the garden through the back of the house. Undeterred, they talked to neighbours and found one four doors down that had easier access to the rear of the homes. The tank was carried over neighbouring garden walls and into the couple鈥檚 rear garden. This provides 48% of the couple鈥檚 water needs including toilet flushing, the washing machine and garden irrigation and has a two-year payback period.

Windows and more

Heating is the area where we had to do most research. The system had to be optimised for our particular needs

Jay Hayter

Elsewhere, the original single-glazed windows are being draught-proofed. Mead didn鈥檛 want to replace the windows with double-glazed units. 鈥淲e would rather keep what we have and renovate it because of the embodied energy in the windows,鈥� he explains. All the heating pipes have been lagged, low-energy lights fitted and eco-paints used for decoration. Hayter found choosing the type of paint particularly difficult. 鈥淭he eco-paint industry is very backstabbing. I found they were very ready to rubbish other people鈥檚 claims,鈥� she says. 鈥淎nd that鈥檚 a problem, because if you are doing an eco-renovation you do tend to rely on the claims made by manufacturers,鈥� chips in Mead.

One popular green bolt-on the couple decided against was photovoltaic panels. 鈥淲e didn鈥檛 go for PV because of the state of the technology and the long payback period, but we would consider it in the future,鈥� explains Mead. 鈥淚t鈥檚 a balance between reducing our carbon footprint and not going wildly over budget and trying to do everything at once.鈥� They also decided against a mechanical ventilation system with heat recovery to cut down on energy use. 鈥淲e looked at a Ubbink system but weren鈥檛 knocked out by it,鈥� says Hayter. 鈥淲e felt if you have that kind of system in a Victorian house it would be difficult to incorporate it without compromising the aesthetics.鈥�

How did it go?

So, how easy was it to get the work done? Hayter used her project management skills to plan the work carefully and prepare a specification. 鈥淲e spent a lot of time writing out the specification as it鈥檚 a bit out of the ordinary for the tradespeople,鈥� she explains. 鈥淭he scope of works also helped us understand what the job was about and it was very useful for the trades as it meant everyone was singing from the same hymn sheet.鈥� They drew up shortlists of five tradespeople for each specialism which included the electrics, general plumbing, the heat pump and plastering, obtained quotes and followed up on references. 鈥淭he guys we chose were really good and wanted to learn about it,鈥� says Mead. 鈥淚 think it was all within their existing skills, it was just a case of them applying their knowledge to a new technology.鈥�

Mead has taken a year off work for this, and was able to do preparatory work such as lifting up the floorboards for wiring and plumbing. 鈥淟ifting the boards was a real knuckle-bruiser,鈥� he smiles. All the M&E systems including the heat pump, hot water tank and solar panel controls have been shoehorned into an original tiny rear extension. 鈥淲e have tried to maximise this space so there was a lot of co-ordination between the plumber, the electrician and all the other trades,鈥� says Mead.

So are the couple pleased with progress so far? The answer is yes; the rainwater harvesting system is providing half of their water, the heating works satisfactorily despite the window draught-proofing not being finished, and the basement is currently unheated as work is still progressing there. They are also already getting all their hot water from the solar panels. 鈥淚t鈥檚 a real success story for us,鈥� says Mead.

So, what do they think would make the job easier?

鈥淚t would help to have a single place to get information. Something like a government-based internet site where homeowners can get practical advice on installing energy-reducing technology,鈥� says Hayter, adding that the Energy Saving Trust鈥檚 website, which is meant to fulfil this role, is hard to navigate and the information it provides is too general. However, she does have a positive message. 鈥淕iven that we鈥檝e done it, anyone can do it,鈥� she says. Given the monumental scale of the task facing the government, this is just as well.