• room logo ABOUT
  • TOPICS
    • MEASUREMENTS
    • SUNLIGHT ACCESS
    • DAYLIGHT FACTOR
    • NATURAL VENTILATION
    • FABRIC HEAT TRANSFER
    • HEATING LOAD
    • THERMAL COMFORT
    • SOUND REVERBERATION
  • INTRO
  • PRINCIPLES
  • OPEN INPUT
  • LOGIN
  • SIGN UP
  • LOGOUT
  • Room dimensions
    • room dimensions
  • Window dimensions
    • window dimensions
  • Window-to-wall ratio
    • window-to-wall ratio
Screenshot ROOM
Room width 5 m

Room depth 5 m

Room height 3 m


Window width 2 m

Cill height 1 m

Window height 1.5 m

Indoor air temperature 21 °C
Outdoor air temperature 15 °C





















































































load construction
  • < empty >
  • < empty >
  • < empty >
  • < empty >




location: London
  • London
  • Belfast
  • Plymouth



21 °C








0.28 W/m2.K

use construction
  • < empty >
  • < empty >
  • < empty >
  • < empty >


0.18 W/m2.K

use construction
  • < empty >
  • < empty >
  • < empty >
  • < empty >


0.22 W/m2.K

use construction
  • < empty >
  • < empty >
  • < empty >
  • < empty >


1.8 W/m2.K

use construction
  • < empty >
  • < empty >
  • < empty >
  • < empty >


0.5 ach



0.2 ach







2

115 W
activity: seated, light work
  • seated, light work
  • working, standing
  • light machine work
  • athletics


12 hours


6

14 W

9 hours


equipment: laptop
  • laptop
  • printer
  • TV


2

30 W

6 hours


1

220 W

0.2 hours


1

45 W

2 hours





















Please see tasks in other tabs
Sunlight from our windows on a sunny day sun day are pretty much predicable. Why are we interested?
Because we can tell when and where we have this:

Sunshine in room
also this, glare that we want to get rid of.

Sunlight glare
You can use design to give occupants this amenity by looking at the solar access. Tasks in this tab help you familiarize with variables needed for the tracking of sunlight, and how your design can benefit from it. Do the tasks on a sunny day would be easier and more interesting :)






Tracking the sun starts with identifying two solar angles: solar altitude and solar azimuth.
Altutide describes how high the sun is, and azimuth tells the orientation where the sun is located,

Solar angles
but where sunlight can reach inside ROOM also depends on which orientation the window faces. Now, find out the latitude of your city, the current local time, and where you get sunlight inside your own room,
input the latitude and local time into ROOM, modify the dimensions of ROOM and the window to which of your own room,
and move the slider of orientation to locate the white patch in ROOM in a position as close to where you get sunlight
in your own room, and now you can tell to which orientation your window faces.
One of the apparent changes when going from one place to another in the world is sunlight. In this task you will observe this change between London, Singapore and Melbourne.
Let's begin with London (latitude = 51.5 degrees North) in the Northern Hemisphere.


London city view
Keep/input the dimensions of ROOM and the window the same as your own room, and make the window face due south (orientation = 0 degree). Now check the white sun patch in ROOM and the two solar angles at the following times: morning(9:00), noon(12:00), and afternoon(15:00) on summer and winter solstices and equinox. You can take screenshots of ROOM at those times by pressing the 'Screenshot ROOM' button below. This shall give you a good overview of sunlight access of your room over the year in the specified location (London). You may note down the number of hours when sunlight access is available on those days and how deep the white sun patch reaches on the floor.
Moving to Singapore (latitude = 1.4 degrees North), close to Equatorial.


Singapore city view
Repeat the analysis and see how the sunlight access is different from which in London,
and then to Melbourne (latitude = 37.8 degrees South) in the Southern Hemisphere.


Melbourne city view
After reviewing the sunlight access in the three places over the globe, try to summarize how sunlight access changes over the day in different times of the year, as latitude varies.
Having understood how to predict sunlight availability in a specific geographical location, we can now start looking at manipulating sunlight access in a room through design. Pick a location (can be that of the project you are working on) and input its latitude,
and input the following room and window dimensions as the base case design



Sunlight basecase
The window is relatively small, with a window-to-wall ratio equal to 10%.



Window-to-wall ratio
Review the sunlight access in the room over the day and over the year in the same way as you did in the previous task. Again, taking screenshots can help you see the variations and note how deep the sun patch reaches on the floor.
Now let's see how the sunlight access changes as we enlarge and move up/down the window, following the steps:



Enlarge and move window
Next, change the depth of room (measured from the facade with window) as follows:



Room depth change
We have covered by far the main design parameters you can play with to manipulate the sunlight access in a room. Changing sunlight access by design often also influences the indoor daylight distribution. You can check how one is associated with another using both this tab and the daylight factor tab.
If you have completed the first 3 tasks in both this and the daylight factor tab, we have a design task for you now.


Visual environment in an indoor space lit with daylight is more vivid and natural,

Daylight office
in comparison with space lit by artificial lighting, which also consumes electric energy.

Artificial light office
The amount of outdoor daylight that reaches the indoor space of your design can be estimated by the indicator "daylight factor".



Daylight factor definition
Daylight factor varies with location in the indoor space and we will focus on the average daylight factor over the working plane Tasks in this tab reviews how the average daylight factor over the working plane varies with different design parameters, and how it is influenced by external obstruction.






As the title suggests, window is the most common element where daylight enters the building. Although real buildings and windows are often more complex than ROOM, this task covers the characterisctis of a window that influence the amount of daylight penetrating through it. The color of the working plane (0.8m from floor) inside ROOM changes with the average daylight factor over it. You can do this task together with task 3 in the sunlight tab to see how daylight factor is associated with solar access.
Input the following room and window dimensions as the base case design, and note down the associated daylight factor (use screenshot to save the result),



Daylight basecase
then observe and note down the changed daylight factor as you enlarge the window, following the steps:



Enlarge window
Glazing is not purely transparent and the light a window allows to penetrate drops as the number of glazing layers increase.
With the enlarged window (5m2), change the light transmittance as follows and see how daylight factor varies



Light transmittance change
Daylight transmitted through the window reaches the internal surfaces (ceiling, floor, wall, window), and only a proportion of that is reflected back to the indoor space and lit the working plane. The amount of light being reflected depends on the light reflectance of the surface,
and some typical values for different colours paint and materials are listed below:



Light reflectance values
Ceiling usually has a bright finish and the common range of reflectance is 0.7-0.8, we will assume 0.7 for the task.


Ceiling finish
A wider range of floor finishes can be found in buildings and we will select 0.5 (birch) for the task.


Floor finish
Light to and from the walls are more likely blocked by internal obstructions (e.g. furniture), and thus light reflection with the walls should consider the obstructions to more closely represent real internal environment. Assuming the obstructions have an average reflectance of 0.5 and the percentage of wall area they block lies between 30% - 70%,
the average wall reflectance with various finishes (with obstructions) can have the following values, and we will pick the highlighted range for the task



Average wall reflectance
Input the following room and window dimensions as the base case design, and note down the daylight factor with different wall reflectance,



Reflectance basecase
then increase the room height and the floor area as follows and observe how daylight factor varies with wall reflectance in the two cases



Reflectance change
Daylight from the sky is partially blocked by obstructions outside the window.



Sky obstructed
The larger proportion of sky view from the window being blocked, the less light can enter the room.



Level of obstruction
The level of obstruction can be quantified by an obstruction angle.



Obstruction angle
Surrounding obstruction is therefore a major factor influencing the available daylight.
Adjust the obstruction as specified, input the following room dimensions, and observe the difference in daylight factor between the smaller and bigger window.



Obstruction basecase
Make sure you reset the reflectance of all internal surfaces to the following values (wall: 0.5 ceiling: 0.7 floor: 0.5) after task 3.
Increase the height of the obstruction, and observe how daylight factor varies with the smaller and bigger window.



Obstruction height
Next, reduce the distance to the obstruction, and observe how daylight factor varies with the smaller and bigger window.



Obstruction distance


To be released
To be released
To be released
To be released
To be released
To be released
Click to continue
Click to skip introduction
arrow
  • You will be seeing how light, air, heat and sound flow in the built environment