3 Reasons to Consider Solar Heat Gain in Architecture
Designing the look and feel of a building’s daylighting is a delicate balance of considerations. Primary among them is how solar heat gain coefficient (SHGC) affects a fenestration system, including wall systems and skylights.
Deciding how much solar radiation to allow through glazing or translucent sandwich panels requires answering the following questions:
- 1. What is the climate where the building is located?
- 2. How energy efficient is your daylighting?
- 3. How much daylighting do you want and how does it affect a building’s aesthetics?
Once those questions are answered, then you can really hone in on what type of fenestration system will best fit your project in regards to the impact of the size, type and placement of skylights, windows or wall systems.
The SHGC is measured on a scale of 0-1, with 1 representing the highest amount of heat allowed into a building through fenestration. A building exposed to intense heat and with little shade requires a lower SHGC, while a higher SHGC would be appropriate for the fenestration of a shaded building in a northern climate.
Beyond the obvious climatic conditions, the surrounding landscape also factors into determining the SHGC for a building’s fenestration. Well-planned daylighting considers a number of issues, including topography, solar orientation, nearby site features like mountains and trees, or reflections off the surfaces of adjacent buildings, paved surfaces and bodies of water.
In a national sampling survey of 1,266 municipalities by energy.gov, solar is the leading clean energy keyword mentioned in their codes. For good reason. Public and private and entities are being rewarded for and, in many instances, legislated into being energy efficient.
Maximizing the use of natural light and minimizing the use of electricity needs to be a priority in any building project, whether new or retrofit. Thermal and solar heat gain performance is key when factoring in the high costs of energy for heating or cooling.
Allowing for higher visible light transmittance is not the objective. In fact, allowing too much natural light can lead to higher cooling costs.
Design + Aesthetics
Balancing function with style results in a superior design that maximizes the use of solar energy. Architects are being challenged to find that balance.
By eliminating uncontrolled sunlight and reducing the reliance on artificial light, architects are allowed to introduce the subtleties and dramatic highlights produced by diffuse natural daylight. It’s not about choosing the product with the highest levels of visible light transmittance, but making an impact with the ideal amount of usable light.
Blending color and shape with new technologies create fenestration systems that satisfy the architect, make the owner happy and allow the contactor to reach his goal of meeting budget.
A perfect way to understand proper daylighting in any project is to utilize daylight modeling software.
Daylight modeling simulations allows architects to understand how a project can minimize the use of artificial lighting, reduce carbon emissions and positively affect the performance, mood and well-being of the occupants. A complete analysis combines a computer program with physical scale modeling to reveal glare patterns and daylight autonomy.
Owners and architects can better plan when they have a clear understanding of lux level requirements and solar heat gain. Modeling is also perfect for Value Engineering, allowing an owner or architect to see where daylighting scope can be optimized to save money and still achieve the desired lux levels.
Kalwall offers complimentary daylight modeling services, including comparing Kalwall to insulated glass (IGU), when being considered for a project in order to help specifiers make better informed daylighting design decisions.