Conversion of an Existing Housing Stock for an Ageing Population: Impact of furniture and appliances on life cycle energy (LCE)

There has been much discussion in the literature on how ageing in place for an ageing population can be made viable. As a part of PhD study on a resource assessment of housing alternatives for the ageing population in New... [ view full abstract ]

There has been much discussion in the literature on how ageing in place for an ageing population can be made viable. As a part of PhD study on a resource assessment of housing alternatives for the ageing population in New Zealand, conversion of a relatively large New Zealand housing type was investigated (early 20th century villas with a central corridor). Three different conversion options for the house were made in accordance with Lifemark design standards. The options range from subdivision (conversion to two smaller units), to varying degrees of shared living (shared guest bedroom and private en-suite bed sitting rooms with all living spaces shared). The aim is to see what is possible when it comes to converting existing houses and through a life-cycle embodied energy (EE) analysis including furniture and appliances, the resource implications of such conversions. Both size and content of houses could be significant when it comes to the environmental impact of housing modifications. The contents can form an important part of the EE of a house as these items usually have short lives making their recurring EE more important. Moreover, it seems that the size of the house also will influence the number of furniture, appliance and tool items and hence the energy involved in them. In this study, the environmental impact of furniture and appliances involved with each design option is calculated using an EE analysis. The calculation uses six hypothetical occupancy scenarios, two before and four after conversion. The EE of furniture, appliances and tool items at various life stages is assessed for each scenario and a life-cycle energy figure per occupant calculated. Results from the EE calculation of the furniture, appliances and tools within the house before and after conversion, show occupancy is the key factor in whether resources can be saved using this approach. Two people living in the original house use slightly less EE related to furniture and appliances per person over 50 years than four people in the same house converted into two separate units. However, the same four people in a shared living arrangement have a 23% saving of life-time EE. This study shows that conversion of existing dwellings in New Zealand seems a way to make ageing in place viable but will not necessarily be more resource efficient. More research is needed to identify the appropriate size of dwellings, design characteristics and living arrangements for the 65+ age group which can accommodate their needs and preferences and at the same time be space and resource efficient.

Keywords: Ageing in place; home modification; lifetime homes; embodied energy, furniture and appliances.