How to Borrow Natural Light - An Architect's Strategy Guide

Summary

This video script delves into the concept of 'borrowed light' in architectural design, emphasizing its importance for sustainable buildings. It traces the history of daylighting back to the 1916 New York zoning resolution and showcases various strategies to maximize natural light, such as interior walls, translucent materials, and skylights. The script illustrates how these methods can transform spaces, making them brighter and more comfortable, and highlights their necessity in modern sustainable design.

Takeaways

• 🏢 The 1916 zoning resolution in New York City was a response to the Equitable Building's shadow, emphasizing the importance of daylight and air access.
• 🌞 Sustainable design practices have made the use of natural daylight a necessity, not a luxury, especially with the increasing focus on energy efficiency.
• 🏡 Borrowed light involves capturing light from the exterior of a home and directing it to interior spaces, which is crucial for rooms without direct exterior access.
• 📏 The sun provides a significant amount of light energy, with a clear day's illuminance being around 10,000 foot candles, despite reductions by clouds and glass.
• 🚿 Interior walls can be designed to collect and disperse light, using reflective surfaces to enhance light distribution in a space.
• 💡 Clear glass transmits the most light, and when positioned above eye level, it maintains privacy while allowing light to pass through.
• 🌫 Translucent materials are effective for borrowed light as they scatter light without direct visibility, providing comfort and reducing eye strain.
• 🚪 Full-height glass walls offer auditory privacy without visual obstruction, making them ideal for spaces with limited exterior window access.
• 📚 Stairways can act as conduits for light, especially when designed to capture and reflect light from above, illuminating lower levels of a home.
• 🪟 Interior windows are functional for light borrowing, allowing light in while maintaining privacy and being less expensive than exterior windows.
• 🌌 Skylights are an efficient means of borrowing light, especially on urban lots where they can be combined with light wells for maximum effect.

Q & A

What was the impact of the Equitable Building on New York City's architecture?

The Equitable Building, being the largest office building in the world at the time, cast a large shadow on its neighborhood. This led to the enactment of the city's 1916 zoning resolution, which aimed to preserve access to light and air at street level and influenced the design of many iconic towers in the city.

Why is the concept of borrowed light important in sustainable design practices?

Borrowed light involves capturing light from the exterior of a building and transporting it to spaces where it's needed. It's a necessity in sustainable design practices as it reduces the reliance on artificial lighting, thus conserving energy and enhancing the well-being of occupants.

How does the sun's illuminance compare to that of a full moon?

The illuminance from a full moon is roughly one foot candle, whereas on a cloudless day, the sun's illuminance is roughly 10,000 foot candles. This highlights the significant amount of light energy the sun provides, which is crucial for daylighting strategies.

What are some challenges in harnessing natural light for interior rooms?

Challenges include rooms without access to an exterior wall or spaces oriented in a way that restricts access to adequate daylight. Solutions involve using interior walls designed to collect and disperse light, clear glass for transmitting light, and translucent materials to scatter light.

How can interior walls help in borrowing light?

Interior walls can be designed to collect and disperse light rather than restrict it. They can gather indirect light from adjacent light-filled spaces and use the reflective nature of surfaces to diffuse light into other areas.

What role do clear glass and translucent materials play in borrowed light?

Clear glass transmits the greatest amount of light into adjacent spaces, while translucent materials reflect, absorb, and scatter light, making them effective for creating walls that borrow light. They help in preserving privacy while allowing the passage of daylight.

How can a stairway be used as a vehicle for borrowing light?

A stairway can be positioned to capture and reflect light from above, either by fully glazing it or using a skylight. This makes it an efficient way to illuminate lower levels that might otherwise be light-starved.

What are the benefits of using interior windows for borrowed light?

Interior windows bring in light from adjacent areas while preserving acoustical privacy. They are less expensive than exterior windows and can be operable to help with passive ventilation, adding functional and aesthetic value to a space.

How effective are skylights in borrowing light, especially on tight urban lots?

Skylights are highly effective for borrowing light, especially when used in conjunction with an interior atrium or light well and surrounded by reflective walls. They can transform tight spaces into well-lit areas by capturing light from above.

What is the purpose of a light tube in daylighting?

Light tubes channel light to where it's needed using highly reflective flexible tubing. They are particularly effective in private spaces or areas where a lot of glass isn't desirable, providing a simple technology to direct sunlight indoors.

How does the concept of borrowed light enhance the perceived dimensions of a room?

By using borrowed light, the perceived dimensions of a room can be naturally increased. This concept works well for spaces with floor area constraints, making them feel larger and more open.