Climate Responsive Environments
The proposed "form follows performance" strategy aims to integrate 10 component parameters towards climate responsibility through a holistic design and engineering approach. The focus widens from individual requirements of a single building / structure to agglomeration of building structures, influenced by specific local climate and site surrounding factors, requiring a synergetical approach for the whole project life cycle. This "grammar" includes aspects of planning, construction detailing, execution on site, operation, maintenance, renovation, reuse and others. The Authors strongly believe that the proposed 10 parameters must be programmed, creatively designed, engineered, balanced and optimized from the very beginning and systematically followed through the whole planning, building and life cycle process. Hence these aspects might used as a individually arranged "checklist", too. The holistic aim is to achieve an overall optimized solution which is practical, climate responsive and sustainable. Finally, the overall grammar of the project should result in minimum amount of disturbance to the existing ecology as well as minimize the carbon footprint based upon a rigorous yet sensitive check-list. Further listings are very rough headings concerning 10 parameters.
Projects (at urban / city planning scale, individual building level) should respond to the local climatic conditions. Each climate zone has developed its own construction systems and methods, which is best suited for the said climatic conditions based upon experience knowledge passed down generations. As a thumb rule, locally available building materials were used which was sensible both in terms of ecology as well as economy.
The goal as Architects, Engineers and Town-planners should be to plan for peaceful co-existence with nature and not 'over' protection from 'hostile' site conditions. Proposed developments should attempt to minimize its ecological foot-print on earth, to support favorable habitat for species, esp. insects and birds, to minimize additional resource requirements to plan - operate - maintain, and to minimize waste (solid, liquid, gases as well as noise) generated during construction and post-occupancy.
The available construction systems and technologies vary a lot due to the climatic, geological and even site-specific conditions as well as our socio-cultural back-grounds and religious beliefs. In terms of sustainability, local building materials should be preferred, to avoid unwarranted logistical challenges and additional carbon emissions associated with mining, manufacturing, transportation and disposal at the end of the life-cycle. Senseful sustainable ratios between "high tech" and "low tech" have to be considered not only for building structure, shell and interiors, but for the utilities as well.
The sun is a constant source of 'free' energy and plays a crucial role in our overall health and well-being. Orienting the proposed built volume should keep in mind diurnal and seasonal movement of the sun increases and overall energy efficiency of a project. The overall energy and daylight gains from the sun depend on the latitude, angle of incidence, associated hours of sunshine, radiation power and the local time of day and season. There should be clear strategy towards shading by neighboring built volumes in terms of catching or reducing thermal energy gains.
As explained earlier, buildings are predestined to generate solar energy if their overall built volumes and specifically the roof surfaces are oriented correctly. Typically, solar photo-voltaic or thermal collectors mounted on a south-facing roof can make optimal use of the sun's rays to generate 'green' energy for the project. Ideally, the required residual energy can be provided by an active solar or wind-based energy generation system. At present, both solar as well as wind-based technologies are widely established across the world. Project sites blessed with solar, wind, water or geo-thermal sources can make best use of the same to reduce operation and maintenance costs and their carbon footprint.
The building envelope serves as protection against wind, rain, moisture, solar radiation and temperature-specific influences. In addition to the overall aesthetics, the energy consumption of a building depends on the envelope detailing too. The building envelope requires a fine balance between the following goals: The low and incident angle of the sun, ensuing passive energy gains, if any. Daylighting for the interiors and glare. The heat-insulating properties of glass, wall and other peripheral surfaces. Durability, operation and maintenance challenges, if any of the proposed material/s and technologies. The life - cycle analysis of the proposed system and materials.
Floor plan/Section zoning:
Floor plan and sectional zoning determines internal spacing of volume, but also areas of specific usage in line with the functional requirements and programming of the building. Architects need to look into 'flexible' or 'changeable' spaces ideally both in plan as well as section in order to arrive at a now and in future 'sustainable' solution. The harvesting of energy (specifically solar energy) is essential for the health and well-being of the occupants and to minimize energy losses while shading devices are important to minimize glare and overheating.
The thermal properties of a building depend to a large extent on the choice of materials and their associated properties. Heat can be transported through transmission, radiation and convection. In this context, the heat transfer of a material is specified with the thermal conductivity (W/mK). The following points need to be kept in mind: 'Grey' or 'embodied' energy needed for producing / manufacturing the material. Locally availability. Ease of construction, replacement and maintenance. Durability. The material / finishes should not be injurious to health (humans as well as domestic animals / pets).
Ventilation is an effective tool for passive cooling, especially if temperatures are cooler outdoors than indoors. Natural ventilation is caused by thermal and / or pressure differentials. Favorable volume design, floor plan, section design and envelope design can increase natural ventilation by using one or more of the following techniques: Courtyard and atrium design enabling night and day air movement merits. Orienting the building / openings towards prevailing wind conditions. Floor & section planning to permit cross ventilation air movement.
Referring to sources:
Bhattacharya, I., Rajapakhsa, U., Reichardt, J.
Novel Concept of Technologies of Sustainable Building Design
Part of the Implementing the UN Sustainable Development Goals, Regional Perspectives book series, first online 30.August 2023
Prof. Jürgen Reichardt
Deadline for manuscript submissions: 30 November 2022 | Viewed by 13750
Interests: 3D-BIM Revit modeling; dynamic climate analysis; energy efficiency; sustainability; changeability; factory planning; steel structures; programming