When there is no opportunity to install roof or vertical windows in order to provide natural light, the light tunnel is an effective solution.
Thanks to the light tunnel, natural light gets into the building illuminating its interior. In the other rooms light tunnels can be an additional source of light.
The amount of light which enters the room via the light tunnels depends on the light intensity outside the building. The more light that illuminates the dome of the light tunnel, the more light is conveyed to the building interior. The below diagram illustrates the full amount of the daylight (lm) depending on the month and cloudiness measured at the light tunnel dome.
The amount of light entering the room is dependent on the placing of the dome.
When planning the installation of the light tunnel, the following elements have to be taken into account:
When planning size and number of light tunnels, the following have to be taken into account:
The table below will provide a guide to choosing the optimum size and type of light tunnel.
|Light tunnel||SLT 350||SLT 550||SRT 250||SRT 350||SRT 550|
|Surface||7 m²||16 m²||8 m²||12 m²||27 m²|
The amount of light
|The simplified light distribution shown below the light tunnel installed in the middle of the room without windows.|
|The same room without windows and with asymmetrical light tunnel placement which can be justified in order to secure better illumination of a determined zone ( e.g desk with computer) in the room. In other instances this type of light tunnel placement is disadvantageous.|
|Depending on the user's necessities, colour of walls (possible diffusion and reflection of the light) and furniture placement - this is a basic scheme of light tunnel placement in a room with a window. The placement of a light tunnel too close to a wall opposite to a window may diminish the overall light in the middle zone.|