Towards taking into account long-term benefits of buildings:
In the best Sustainable Communities Initiative, evaluating the buildings costs takes into account the investment and operation. It is now recognized that more careful design allows a cheaper construction.
Very few projects take into account the quality of life, ease of use, fun at work, the impact of a healthy indoor… Yet numerous studies have accurately assess the benefits arising from such situations.
Nevertheless the consideration of these items on the life of the building can have a decisive influence on the program, its design, construction and maintenance.
Induced costs such as transportation represent a considerable share. Thus, it is common to observe that, in office buildings, the weight of travel from home to work is more than 600 kWh / m². Year.
Example of an overall cost analysis on an office of 50m ² comparing three solutions:
– A solution minimizing insulation
– A solution that has a high insulation
– A solution towards a sustainable building (natural insulation, bioclimatic design, soft travel, air quality …)
Investment cost Total cost extended
Life Cycle Costs tools are adapted to compare solutions
In France, there are many Life Cycle Costs. A comparison made in 2012 has shown a very clear differences between the tools. This highlights the influence of hypotheses which have very large uncertainties. Indeed, the forecast energy consumption are subject to the vagaries of regulation and management, maintenance costs difficult to quantify, the evolution of energy prices is uncertain, the unkown life of the building… LCC calculation is an attempt to approach a cost including certain deferred costs, and can not in any way constitute a commitment or a figure to compare with reality.
The calculation must be performed to compare solutions or answer a specific problem.
A remarkable tool:
A free software has been developed by the Association Sustainable Mediterranean Buildings (BDM). Although it is possible to calculate the overall cost of a single solution, this software is used to compare different solutions and develop a “sustainable” solution, taking into account the impact of materials, occupant comfort and energy performance building.
It combines ease of use, richness of cost items and proposed hypotheses.
This tool will be tested under MountEE on some pilot projects.
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