Pre-Design Sustainable Decisions

Incorporating Sustainable Principles in the building design is a key method to ensure that the negative environmental impacts are reduced, also occupant wellbeing and comfort parameters (thermal, visual, and psychological) are enhanced. However, instead of “force-fitting” the sustainable interventions at the final stages of design when the building layout is almost fixed, it is beneficial to the project to integrate sustainability from the very beginning. The sooner the sustainable goals and strategies are defined, the more sustainable and low cost the project will be. So how early in the design process should the project team incorporate sustainability? The answer would be – before the design phase starts.

The main objective of Pre-Design analysis is to understand the project context and determine a set of key sustainable goals and strategies that shall act as a data book the architects can refer to make high-quality design decisions. This is crucial as the design stage decisions will determine the building's performance during the operational stage. The major steps in Pre-Design analysis are as follows:

1. Macroclimate Analysis

The larger area – district, state, or country will fall under a specific climatic zone. This climate is known as Macro-climate. Understanding the general climate data such as Temperature, Humidity, Rainfall, Seasonal Variations, Solar Radiation, Wind Rose, etc. helps us to streamline the strategies that can be implemented in the building design.

2. Microclimate analysis

Micro-climate is the variations in localized climate around a building caused due to the presence of slopes, hills, water bodies, local winds, vegetation, and other buildings. With the knowledge of local climate and the site contextual parameters, the design team can take major decisions regarding the masterplan layout- location of buildings, service areas, landscape, open spaces, etc.

3. Massing and Orientation

Diverse options are tried out to determine the best massing and orientation strategies that will reduce the energy consumption of the building considerably. This is done using computational modeling with the climate data incorporated. This is the most important passive design strategy to lower energy costs and enhance occupant comfort.

4. Adaptive Thermal Comfort

Mechanical systems are used to cool or warm the spaces within a building to ensure that the majority of the occupants are thermally comfortable. However, this increases the energy demands of the building. After the massing and orientation of a building are finalized, the internal layout can be designed in such a way that very less energy is required for the zone to fall within the thermal comfort bandwidth. For e.g. In India, the rooms that need air-conditioning such as computer labs can be placed on the ground floor facing north, where solar radiation is the least.

5. Passive Design Strategies

The climate responsive strategies, apart from massing, orientation, and internal layout, that can be incorporated in the building design are analyzed and shortlisted so that the design team can make effective decisions in making a sustainable habitat. The parameters include Solar Shading, Cool Roofs, Fenestration, Insulation, Daylighting, Natural Ventilation, Thermal mass, Evaporative Cooling, Vegetation, etc.

6. Sustainability Targets

What gets measured, gets managed. Hence it is important to set goals and targets that will predict the building’s sustainability performance at the conceptual phase. These Key Performance Indicators (KPI) can be useful for later assessment of the building as new design parameters are added. A few important KPIs of a sustainable building are Energy use, Water use, Waste Diversion, Life Cycle Costing, etc.

Sustainable buildings are often misconceived as time and cost intensive. This is due to the lack of sustainable interventions from the conceptual design stage itself. With the right passive design strategies, the project team can reduce the energy and water demands on the mechanical systems to provide thermal and visual comfort to the occupants. This shall also reduce the pressure on renewable energy sources such as PV panels to meet the entire building energy demands.

Quoting Sir Buckminster Fuller, “The best way to predict the future is to design it.”

Let us start today to make our buildings healthier, sustainable, and future proof.