This house is a single storey, 70 year old, solid, well maintained weatherboard home. It is situated on 100 acres in an exposed, elevated location a few kilometres to the back of Apollo Bay.
The Owners' Aims
The owner’s interest in the assessment arises out of concern about carbon emissions from inefficiencies in the house and an interest in the potential for installing solar. The owner had recently replaced an old electric storage hot water system with an energy efficient heat pump Hot Water System.
The Assessor's Findings
The assessor's roof cavity inspection revealed good double-layer insulation in the roof except where there are exposed beams. There are single-glazed windows throughout the home, some facing the sea, and most without window coverings; the structure of the windows will not allow double glazing.
The kitchen featured the older style gas cooktop with electric oven. The main house heating was provided by the slow-combustion wood fire which, as the assessor explained, was drawing in cold air through existing draughts in the building envelope. The assessor identified other draughts from the ceiling penetrations made for the downlights that compromised the effectiveness of ceiling insulation.
In the bathroom, the shower head was identified as an inefficient3-star rated unit that was wasting both water and the energy required to heat the excess hot-water.
Solar potential was identified with a well situated shed with large north facing roof space located not far from the house.
The Assessor's Recommendations
The assessor first recommended the thermal performance of some single-glazed windows could be improved 100% with 'secondary glazing' (Ecomaster product). Window coverings with closed pelmets then could be installed and cellular blinds considered–‘Veneta’ honeycomb blinds are a low cost, DIY solution–to further combat the loss of heat and to improve cooling around the windows. Also, although only five years old, the downlights could be replaced with IC rated closed unit LED down lights fitted by an electrician. The ceiling insulation could be improved at the same time. Draughts around the doors could be reduced with 'Draught Dodgers' by Ecomaster, product no. EM15D.
Other cost-effective savings could come from replacing the inefficient 3-star showerhead with a low-flow showerhead (such as the Methven Kiri Satinjet Ultra Low Flow purchased from PURE ELECTRIC). This change would save both water and costs of heating the excess hot water in the current system. In regard to solar power potential, the assessor was encouraging-suggesting the near-by shed roofing could house a significant solar panel array-and he saw multiple advantages, especially in advancing the fuller electrification of the house which would dramatically reduce the home's carbon emissions output.
From The Owner's Viewpoint
“The assessor suggested that if I want to install solar, it would be best to upgrade the shed roof so that I could have a 10kW capacity solar system installed. He explained that this would generally provide for greater overall electrification of the home. This would allow me to power the heat pump with solar as well as installing an efficient contemporary split system (such as a Daikin) to substitute/support house the wood fire. If I wanted to, I could also consider replacing the gas cooktop with an induction cooker.”
