Salvaged materials includes doors, bath and toilet

Stephen Bray of Alternative Energy Ireland, who supplied the solar system notes that access was the most difficult issue: “It was an awkward install but because it was a flat roof we were able to orient the panels six degrees west of south – it’s perfect orientation.

“It’s just doing water,” said Bray. “60 to 65 per cent of the house’s hot water need should be covered – 100 per cent of need in the summer, tapering down to forty per cent in the winter.”

The solar system stores hot water in a 250 litre tank and uses stainless steel piping, cylinder and frame: “It’s better for longevity,” said Bray, “you won’t get corrosion and leaking in the piping.”

Bray estimates an eight year pay-back on the capital investment of installing the system.

Flowing back
Aside from reducing energy need and improving the efficiency of the heating systems, Cleary made the decision to go a few steps further in the quest for sustainability.
A rainwater harvesting system was purchased from Molloy Precast. The company’s Michael Cahill explains: “It’s a 3,500 litre storage system. Most people in Dublin [who use rain water harvesting] use it for the toilets but it can also be used for all [non-potable] cold water in the house.”
 
“We use it for the toilet cisterns and washing machine,” said Cleary, who has found that the tank provides four to five days worth of water: “A four day dry spell means it goes over to the mains again.”

Cahill explained to Construct Ireland: “There is a 750 millimetre vertical pump that seeps it at a steady pressure of 30psi, or two and half bars in metric terms. If it’s dry, on the rare, rare occasion [in Ireland] the flow switch brings in the mains water.”

In addition, as an extra touch, as many materials used on the house’s interior as possible are salvaged or recycled. Bamboo work tops were specified in the kitchen, salvaged timber flooring, originally from a Dominican sports hall, and the sink and bath in the bathroom were salvaged – an approach also applied to the existing resources within the house. “The old doors were much nicer than anything we could get new, so we stripped them and kept them”, said Cleary. A-rated appliances were chosen in the kitchen, and cold cathode spotlighting has been used as an alternative to CFLs throughout.

The fabric, heating and lighting improvement measures have had a significant impact on the energy efficiency and notional Building Energy Rating (BER) of the house – the house cannot have an official rating, given that BERs are not available for existing dwellings until January 2009. The notional BER marginally exceeds the newest 2007 Part-L building regulations, rating at the upper end of the B1 band at approximately 80-85 kilowatt hours per metre squared, per annum – close to an A3 rating. In fact, the addition of on-site micro-generation of renewable energy would easily lift the house to an A-rating.

The question is: was it worth it? In practical terms, yes. Clearly has a larger, more comfortable and energy efficient home that costs less to run – a recent electricity bill, for example, came in at just e33 for two months. Cleary herself estimated in her column in the Sunday Business Post that the house is at least 40 per cent more efficient than most of the 500,000 new houses and apartments built in Ireland in the last decade. She also made a rough calculation that, “this house will use around e900 of gas and electricity every year, a saving of some e800 annually on typical heating and running costs.”