Smart Orientation of Buildings to Reduce Energy Costs in New Construction Projects

Reducing the amount of energy required to operate a constructed facility has become as much of a priority within the design and construction industries as creating a building designed to meet particular structural and aesthetic standards. Perhaps one of the most effective and frequently ignored methods for improving overall building energy efficiency is determining in advance where the building should be placed. Smart orientation of a building during the planning stages can greatly impact how much energy will be used by that building, its occupant’s thermal comfort levels, and its long-term operational costs.

With energy costs continuing to rise and sustainability becoming increasingly important within the construction industry, architects, planners, and developers are placing greater attention on making smart orientation decisions during the initial phases of the building design process. As you read this article, you will see how smart orientation of buildings at the early stages of building construction can result in lower energy demand, reduced operating expenditures, and improved overall performance of the building.

Importance of Building Orientation

The basic principles for building orientation involve strategically aligning the structure with respect to the sun’s trajectory, as well as the natural elements around it. This sunlight orientation for architecture will determine how much sunlight and wind the building receives during different parts of the day and throughout each season and will have a direct influence on the heating, cooling and lighting loads of a building. Many studies have shown that properly oriented structures reduce energy consumption significantly, providing longstanding operational cost savings and enhancing the comfort level of the inhabitants.

The influence of orientation is based on passive design principles, which take full advantage of the effects of the natural elements in the environment instead of relying solely on mechanical equipment to achieve the same result. In contrast, when orienting structures, a builder may want to maximize the amount of direct solar heat gain in colder regions while minimizing the amount of heat gain in hotter areas; therefore, orientation should be the first decision made that will affect the long-term energy performance of the building.

Sunlight, Heat Gain, and Seasonal Efficiency

The movement of the sun during the seasons should be the most important guide to the general direction of Early Design Development. The south orientation of buildings typically has the longest duration of direct sunlight on their exterior surfaces during the winter months in most temperate climates, resulting in reduced heating loads. In contrast, large, exposed surfaces to the east (morning sun) and west (afternoon sun) will increase cooling loads in the summer months. 

Sun Path Analysis is used by architects to establish the best orientation for façades and window locations. For example, if a building is oriented along the long axis of the east–west direction, it generally will have more southern exposure for natural heating during the winter months and less intense direct solar heat gain during the summer months. This can result in reduced cooling costs when combined with shading devices. 

The southern orientation is even more important when designing for the glazing and insulation of windows. South-facing windows with high solar heat gain coefficients enable the capture of the sun’s radiant energy in the winter months, while strategically placed overhangs limit the amount of radiant energy from the sun that enters through the windows in the summer months. Conversely, the northern orientation will allow for continuous, diffused sunlight to enter a building throughout the entire year, while limiting the amount of direct solar heat gain.

Air movement, Natural Ventilation, and the Microclimate Effect on buildings

The orientation of a building will also determine the usefulness of ventilation by aligning buildings in a manner that utilizes prevailing wind currents. The reduction of the cooling load from mechanical HVAC equipment will greatly depend on the rate of natural air movement which is available. In a transitional climate, a nighttime breeze may aid greatly in making indoor spaces more pleasant for occupants. Careful and deliberate consideration of wind flow when situating buildings helps reduce the effects of humidity and associated costs of maintaining moisture within the building envelope.

Urban design professionals continue to discover how urban environments contribute to the development of microclimates. The configurations of buildings with adjacent green spaces and bodies of water affect the flow of wind and shading, thus consequently, the pattern of energy usage. However, it is critical to conduct an analysis of multiple variables to develop an optimal orientation in an urban setting to maximize energy trim levels.

Building Orientation Influences Lifecycle Costs

In addition to energy costs, building orientation will also impact the lifecycle costs of a structure over time; for instance, as more passive solar energy is utilized in buildings, the operating costs (heating/cooling) can eventually exceed the initial investment (cost) for structure design. Many times, the operating cost savings alone will be enough to recoup the time spent analysing the building’s orientation.

When planning for commercial construction, it is beneficial to include building orientation analysis as part of all the other design parameters such as wall (façade) types, materials used in the construction process and the integration of building systems. Recent information indicates that by using Building Information Modelling (BIM) tools, a building’s orientation can be leveraged to create maximum energy and operational savings across a wide range of terrain and climatic conditions.

Integrating with Sustainable Products

Optimizing a building’s orientation is beneficial for a building’s owners, but goes beyond utility costs. Optimizing the Orientation of a Building for Sustainability aligns with sustainable design, thus developing the orientation of a building is directly related to our social and environmental regulatory goals.

The site selection and orientation of a building have been given special significance by the LEED and passive house green building systems because of their direct effect on a building’s energy consumption and carbon emissions.

Building(s) that have taken into consideration their environmental responsiveness will consume less energy from non-renewable energy sources, will create fewer Greenhouse Gases, and will provide a healthier indoor environment.

The synergy between the orientation of a building and the design trends of regenerative design and passive house principles supports a healthy total ecosystem and the decrease of operational energy.

The lessons learned from innovative residential architecture can be applied to the design of larger commercial and mixed-use spaces, passive design strategies focused on the energy efficiency of the thermal envelope and solar gain are accepted as the standard in luxury architecture.

Contractual Insight To Construction

This section illustrates some examples from previous work which demonstrate the value of how orientation impacts a project.

For example, a residential project that has been orientated to maximise solar gain has resulted in less dependence on artificial climate control systems than if it had been orientated to face south.

In high-performance office buildings, by orientating them to balance out the amount of daylight and heat that is being received, it has led to more comfortable environments for building users, plus it has reduced both lighting and HVAC (Heating, Ventilation & Air Conditioning) costs.

When combined with Building Information Modelling (BIM), the results of orientation analysis allow for the creation of comparison scenarios for energy performance, thereby allowing the design team to identify design alternatives that produce as close to maximum energy savings as possible.

Sustainable renovation trends are also demonstrated in projects where the architectural firm has preserved and reused an older building while improving the overall performance of the building through strategic orientation and passive methods.

The Role of Early Planning and Data-Driven Design

Effective project planning (early) is a common trend observed in many projects that have had a high level of success. Once a particular site has been identified, the speed at which orientation is decided may not receive due consideration; however, the decisions made during this phase can have far-reaching effects on expense throughout the project’s lifecycle. Energy modeling and climate data should be employed as soon as possible to allow the design team to evaluate various orientations and select the one that most effectively minimizes the annual energy demand of the facility.

Through the integration of material selection (e.g., high-performance glazing and insulation), shading devices (e.g., awning or window overhangs), and landscaping (e.g., summer shading trees), the combined impact of each will produce a multiplicative benefit. Ideally, during the planning phase, orientation-related factors should be considered along with structural, mechanical, and aesthetic considerations as part of an integrated design process.

In conclusion

Proper orientation of buildings plays a vital role in environmentally friendly design and is an effective way of lowering your energy operating costs during a building’s entire life cycle. By considering how their buildings will sit relative to the sun’s movement and prevailing wind patterns while integrating these ideas into the surrounding natural geographic area, architects and builders can maximize passive design, lower the cost of operating the buildings and respond to the demand from the market for sustainable buildings.

No matter what your project is — large commercial projects or residential designs — applying orientation principles in the design phase of your project will give you the best possible chance of creating a building that operates for many years with the least amount of energy consumed. The long-term financial and environmental benefits of investing the time, knowledge and money into this important first step in building design and development is one of the best investments you can make in today’s construction business.