Barriers & Challenges to nZEB
Social & Organisational barriers
Saving energy is not simply a technical issue, but it also depends on the lifestyle of residents and correct stock management:
The amount of energy used in a building depends not only on the design specification and materials used, but also on the lifestyle of the residents and the housing management services provided. The acceptance of what is considered an adequate level of thermal comfort varies widely with differing personal and cultural standards; it seems that the human dimension is rarely considered by engineers.
In terms of savings in the amount of energy used, allowance also has to be made for the ‘rebound effect’ i.e. an actual increase in energy consumption once the energy saving measures have been introduced. This is especially common in low-income households where a choice can be made between having lower energy bills or paying the same amount of money but having higher comfort levels with increased heating.
There is a cost involved in community outreach to ensure that residents have a good understanding of how they can live in their home to optimise their use of energy. It is estimated that this is 15 % of the total cost of refurbishment. These costs include advising and informing residents and where necessary, decanting residents into temporary housing to allow work to be carried out.
Adequate training and support of residents will be needed to maximise the functioning of low energy housing but also to enable informed decision making by residents. This was felt to be particularly important where there is divided or cooperative ownership and every decision concerning the building has to be agreed with all the owners, otherwise only partial retrofit measures can be undertaken. It is slightly easier with cooperatives where the cooperative owns the building and can invest the resources, but even so the residents will need to be consulted and in practice it may be difficult to achieve approval from a large majority of residents.