Eco NW - State of the region
Resource flows and impacts of production and consumption in the NW
Construction & urban development
Today, there are roughly 2.9 million dwellings in the NW: net of clearances, nearly 13,000 dwellings will be built - about 143,000 new houses over the next 11 years, or 585,000 new dwellings to 2050, a total 20% increase over today's levels. The REAP tool was used to quantify the materials and supply chains involved in the average NW house:
- Inhabited by 2.35 people, 0.4 cats and 0.3 dogs
- It consumes 9,127 KWh of energy, producing 5.18 tonnes of CO2
- It weighs about 150 tonnes with another 137 tonnes for the foundations
- It requires 0.50 tonnes of materials each year for maintenance and repair
- Most of the energy is derived from natural gas (66%) and electricity (24%)
Construction and materials for the average house produces 61 tonnes of CO2: if depreciation (NPV) over 60 years is assumed at public discount rates, this CO2 can be allocated at 1.9 tonnes a year, plus maintenance and repair at a further 0.2 tonnes of CO2. This can be contrasted with the operational use, where by current standards, direct energy demand produces an average 5.38 tonnes CO2 per year, or over 2.5 times the emissions from construction and maintenance. On purely environmental grounds, the proposal of the '40% house' project for demolition and replacement of the least efficient third of the housing stock is justified, as the footprint cost of construction would be more than offset by the footprint gain from ultra-efficient houses.
