As an architect, one of the key decisions when planning for a project is determining which types of glass are the right fit for your job. The combination of the right glass and having the right supplier is the formula for a successful job. With over 20 years experience, we'll look at some of the most important factors to consider while specifying glass in this blog.
When evaluating glass samples, look at them outside on a cloudy day.
Examine the jobsite in various lighting conditions and at various times of day.
For a 40- or 50-degree angle, look at triple-silver low-E coatings.
Turn a sample over to view the interior reflected aesthetic as well as the reflectivity of the glass. Keep a distance of around 10 feet between you and the object.
What to consider to top performance in Architectural Glass
The U-value measures the insulating qualities of the glass, or how much heat flow or heat loss happens through the glass as a result of the temperature differential between interior and exterior temperatures.
U-values indicate how efficiently an insulated glass unit (IGU) keeps hot or cooled air within. The lower the number, the more effective the insulation. U-values typically vary from 0.1 (very little heat loss) to 1.0 (very significant heat loss) (high heat loss). The number of BTUs that will travel through each square foot of space per degree of temperature variation from one side of the window to the other is the U-value of a window.
R-value is used to test the performance of most other components of the building envelope, such as walls, floors, and roofs.
How to Calculate R-Value?
Divide 1 by the U-value figure to get the R-value. A U-value of 0.20, for example, equals an R-value of 20. (1 divided by 0.20). Divide 1 by the R-value to get the U-value—a 4.50 R-value yields a U-value of 0.22.
Solar Heat Gain Coefficient (SHGC)
A measurement of how efficiently a product prevents sunlight-induced heat. The lower the SHGC, the less solar heat is transmitted, and the occupants are more comfortable inside. In cold areas, the right SHGC can assist in maintaining warm inside air, while in hot ones, it can help keep pricey cool air-conditioned air.
Visible Light Transmission (VLT)
The percentage of visible light that travels through glass is known as visible light transmission (VLT). VLT may enhance daylighting and, if intelligently planned, can help balance electric lighting and cooling demands. A greater VLT increases daylighting, whereas a lower one increases privacy. Glare can be avoided by controlling VLT.
Light to Solar Gain Ratio (LSG)
The VLT is compared to the SHGC using the light to solar gain ratio (LSG). A greater LSG ratio helps brighten a space.
The orientation of a building has a significant impact on its energy efficiency and occupant productivity. Depending on the course of the sun in the summer vs the winter, solar heat intake and daylighting can change dramatically. Excessive heat gain or glare difficulties can occur if these are overlooked, compromising energy efficiency and occupant comfort. The arc of the sun has a distinct effect on each façade:
North: All-day indirect sunlight
South: Solar exposure throughout the day
East: Direct light at low angles in morning
West: Direct light at low angles in afternoon