Summary of cost effective upgrades in Auckland region [PDF, 250.7KB]
The extra cost in each table refers to the costs over and above what a more standard component or system would typically cost to purchase initially.
Comfortable temperatures
The following improvements will help make the house more comfortable while needing less heating or cooling over the year, therefore saving on energy costs. (Note that an accurate yearly savings figure cannot be determined by adding two or more thermal improvements together.) The yearly savings are a result of the lower need for space conditioning energy use only. Figures are based on the needs of typical spec homes.
| Thermal improvement | Extra cost | Yearly savings | Thermal benefit |
|---|---|---|---|
| HOUSE ORIENTATION | |||
| Living areas facing north, garage facing south | Marginal | $50 | Good |
| WINDOWS | |||
| Standard, aluminium-framed double glazing is the most cost-effective solution, while cheap electricity is available | NA | NA | NA |
| STANDARD CONCRETE SLAB | |||
| Living areas have exposed concrete slab (i.e. polished), with all other areas carpeted | $700 | $100 | Good |
| Living areas have exposed concrete slab (with finish), other areas tiles | -$2,200 (savings) | $110 | Very good |
| COMBINATIONS | |||
| 50 mm expanded polystyrene insulation under concrete slab + exposed slab in living areas, otherwise carpeted | $2,800 | $210 | Very good |
Energy efficiency
The following improvements will help make the house cheaper to run. (Individual improvements can be added together to provide combined extra costs and yearly savings.) The yearly savings is the estimated benefit in lowered energy costs resulting from better appliance efficiencies.
| Energy improvement | Extra cost | Yearly savings (per household) | Energy benefit |
|---|---|---|---|
| RENEWABLES | |||
| Photovoltaic-ready house (installing cabling only) | $400 | NA | NA |
| 3 kWh grid-connected photovoltaic system fully installed | $10,000 | Difficult to determine | Difficult to determine |
| APPLIANCES AND LIGHTING | |||
| Correctly-sized heat pump | $0 | $50 | Good |
| 4 Energy Star fridge-freezer (380 litres) | $100 | $60 | Good |
| All lighting energy efficient (CFL or LED) | $300 | $150 | Very good |
Water management
The following improvements will help to manage water resources better. (Individual improvements can be added together to provide combined extra costs and yearly savings.) The yearly savings is the estimated benefit in terms of saved water over a typical year given typical occupants.
| Water improvement | Extra cost | Yearly savings (per household) | Water benefit |
|---|---|---|---|
| SMALL FITTINGS AND APPLIANCES | |||
| 4 star or better WELS toilets | Marginal | 1,600 litres | Good |
| 4 star WELS kitchen and bathroom tapware | Marginal | 2,300 litres | Good |
| 4.5 star WELS dishwasher and washing machine | $300 | 19,500 litres | Very good |
| 4 star or better showerheads | Marginal | 57,100 litres | Excellent |
| RAINWATER TANK SYSTEMS | |||
| 1,000 litre water tank with feed pump to garden | $2,400 | 93,000 litres | Outstanding |
| 5,000 litre water tank with feed pump to laundry and WC | $4,700 | 120,000 litres | Outstanding |
| 25,000 litre water tank with feed pump to whole house (check council regulations) | $7,400 | 138,000 litres | Outstanding |
Updated: 20 September 2023