Principles of Design with Climate Lecture #6 Visual Comfort and Daylighting-Fall 2024 PDF

Prince Mohammad bin Fahd University College of Architecture and Design Department of Interior Design ARCH 2341 Principles of Design w/ Climate Fall 2024/2025 Lecture #6 Designing for Visual Comfort Instructor: Lujain Khalid Al-Eidi  APART...

Prince Mohammad bin Fahd University College of Architecture and Design Department of Interior Design ARCH 2341 Principles of Design w/ Climate Fall 2024/2025 Lecture #6 Designing for Visual Comfort Instructor: Lujain Khalid Al-Eidi  APART FROM DEFINING THE THERMAL COMFORT STANDARDS FOR THE BUILDING, IT IS ALSO IMPORTANT TO DETERMINE THE VISUAL COMFORT REQUIREMENTS FOR THE SPACES IN THE BUILDING FROM THE INITIAL DESIGN STAGE. Designing for visual comfort How can we design for better visual comfort? There are several factors that can be used as keys to designing visually comfortable environments: Achieving the proper lux levels by utilizing Access to views of Daylight provision in natural daylight to the outside sufficient quantity light a building Combination of Uniform distribution Using enough task natural and artificial of light lighting light Light control to Occupants control ensure the absence An aesthetically can adapt the light of glare and high pleasing space to suit their needs contrasts Visual Comfort & Daylighting Visual Comfort Theory and perception of light Daylighting analysis and design Passive & Active Solar Lighting Shading devices and techniques Case study Visual Comfort & Daylighting Visual Comfort Theory and perception of light Daylighting analysis and design Passive & Active Solar Lighting Shading devices and techniques Case study  Visual Comfort Visual Comfort is that condition of human mind in which it feels satisfied with the physical reaction between human eye and quantity & quality of Light. The presence of daylight, the contrast between task lighting and ambient lighting and presence of glare, combined with access to quality views, all play a role in our overall visual comfort.  Visual Comfort visual comfort depends on our ability to control the light levels around us. A careful balance between natural and artificial lighting is recognized as the best solution for our comfort and health. Tools available to achieve visual comfort include: The size and position of the doors and windows, the orientation of the facades, building materials and equipment, solar protection devices and the reflectance of the surfaces  The visual comfort can be measured qualitatively as well as quantitively. The visual comfort can be measured qualitatively as well as quantitively. Visual Comfort Theory and perception of light Daylighting analysis and design Passive & Active Solar Lighting Shading devices and techniques Case study Theory and perception of light Quality aspects of light Light source Light distribution Light tone and color Light intensity Brightness: it’s depends on the adaptation of the eye. Contrast: It is the difference between the brightness of an object and that of its immediate background. Glare: Excessive contrast cause glare.  Theory and perception of light Candelas Lumens Lux Theory and perception of light Theory and perception of light Quality aspects of light Luminous Flux: Amount of light flowing through a space is called Luminous flux. Its unit is Lumens. Luminous intensity: Intensity of a light source is its luminous flux per unit solid angle. Its unit is Candelas Illuminance: Total luminous Flux incident on a surface. Light falling on a surface. Its unit is lumens per unit area. ▪ Lux=Lumens/m2 ▪ Footcandles= Lumen/Foot2 Luminance: Light reflected from a surface is called luminance. Its unit is (Candelas/m2). Visual Comfort Theory and perception of light Daylighting analysis and design Passive & Active Solar Lighting Shading devices and techniques Case study Daylighting analysis and design Natural daylight is the light source to which our eyes are naturally adapted, so we always find it more comfortable and attractive than artificial lighting. Spaces lit by daylight appear naturally beautiful and spacious. It plays a major role in defining the aesthetic quality of a space and the health and wellness of the building user. Daylighting analysis and design Exposure to natural light improves: Mood Employee and visitor satisfaction Student performance and learning Healing (especially in hospital environments) Productivity Cognitive function Circadian rhythms ) ً‫عاشا‬ َ ‫ع ْل َنا النهار‬ َ ‫م‬ َ ‫ج‬ َ. ً‫ع ْل َنا الليل لِبَاسا‬ َ ‫و‬ َ ‫ج‬ َ ‫و‬ َ ( - ‫قال تعالى‬ Daylighting analysis and design In offices, In hospitals, having a better view out of an office It has been observed that patients in rooms window is associated with better that are well daylit need up to 30% less overall performance, with productivity pain-relief than others that they recover increased by 7%–12% faster and return home in much better spirits. Good Design Poor Design Good Design Poor Design Sources of Daylight Daylighting analysis and design The daylight that enters a window can have several sources: 1. Direct sunlight, 2. Clear sky, Clouds 3. Clouds, and Reflections 4. Reflections from the ground and nearby buildings Reflections Daylighting analysis and design Glare The loss of visual performance or discomfort produced by an intensity of light in the visual field greater than the intensity of light to which the eyes are adapted. It is a result of excessive contrast, or of light coming from the wrong direction. The contrast between the bright outside environment viewed through a window and the darkness of the interior space creates glare. Wide windows are used with light reflectors to send light deep into the interior, BUT they can be a source of glare except on north windows. Daylighting analysis and design Glare There are two basic methods to avoid glare and reduce brightness contrasts: 1. Sensitive interior design and 2. Daylight light controls.