Friday, October 03, 2008

Fit twice as many students in computer lab with better design

New Design of a Blended Learning SpaceThis is to suggest that smaller computer equipment and careful room design can double the capacity of computer equipped teaching spaces and make them more flexible. The space required can be reduced from 4 m2 per student to 2 m2, comparable to the space allocation for non-computer equipped collaborative learning rooms.

These computer equipped rooms can then be used for blended learning: combining individual computer based work, small group work, group teaching and language laboratories. The learning style need not be fixed by the instructor, with each student selecting their own style. A compact design will allow the instructor and the students to hear and see across the room.

Bodies such as the Australian Government are advocating one computer per student, but are only budgeting for the cost of the computers, not the doubling of floor space which would be needed to accommodate them using current designs.

Computer Labs Have Taken More Space

It has been the practice at universities, vocational training centres and schools to have "computer labs": rooms specially fitted out for computer use . More recently similar layouts have been used in the "learning commons" of educational libraries. Larger desks are provided in labs and commons to accommodate one computer per student. These rooms use twice the floor space of "Cabaret-Style" collaborative learning rooms, which do not allocate a computer to each student.

Seating Densities for Different Learning Styles

Photograph of students at work in the MIT TEAL classroomThe MIT Technology Enabled Active Learning (TEAL) rooms have 2.38 sq m per student. The University of Melbourne guidelines recommend 2 m2 per student for a "Cabaret-Style" Collaborative Learning room. When computer equipped, these rooms have one computer for every three or four students. Computer Lab equipped for teaching have required up to 4 m2 per student.
Seating Density
Type of Spacem2 per student
Lecture Theatres1.0
Seminar Rooms, tight schoolroom set-up1.5
Seminar Rooms, schoolroom with more table space2.0
Collaborative Learning "Cabaret-Style" with room to move and larger tables2.0
Computer Lab - Student Access3.2 - 3.5
Computer Lab - Teaching3.5 - 4.0

Adapted from: "University of Melbourne Teaching Space Design Guidelines", University of Melbourne, 15 December 2004.

Old Design

Old Design of Computer LabConsider a computer lab that is 7.2 x 12 m, with four rows of five desks each 1200 x 900 mm. In this case the rows of desks run down the room. Two rows of desks face each side wall. Two rows of desks with the students sitting face to face, form one large table in the middle of the room, with circulation space around it. A teaching space at the front of the room has a whiteboard/projection screen and a console with audio visual equipment and controls.

A large proportion of each desk top is reserved for a computer monitor, and PC box. Space is provided on the desk for the student to have text books and notepaper while using the computer.

For 20 students, the 86 m2 room provides 4.3 m2 each, slightly over the UoM guidelines. Can the room be made to accommodate more students, but still allow each enough space to operate a computer?

Suggested Layout

New Design of a Blended Learning SpaceSmaller, curved desks with slim computer monitors can be used with offset seating. There is then room for an extra two rows of desks, forming a second island, doubling the seating capacity.

Bulky PC boxes can be removed from the desktops to provide more work space. Less desk space is needed as most instructional material will be provided via the computer and the student will type their notes directly into the computer. However, enough space is provided for an A4 pad while using the computer, or an A4 pad and a textbook when the keyboard is pushed under the monitor.

The table end nearest the whiteboard can have an oval shaped raised area added for the instructor's lectern, with the audiovisual equipment underneath. The other table ends can be similarly rounded and provided for wheelchair and other accessibility access. A second whiteboard can be placed at the other end of the room for breakout group work with provision for a second projection screen. Additional display screens can be placed on the side walls, if needed.

Smaller Computer Desk for Smaller Computers

The size of computer desks in current use were determined when computers had large CRT monitors and processor boxes. The user had to have access frequently to the PC box to insert floppy disks or other rotating media. Also there had to be desk space for paperwork. Computers now use slimmer LCD screens and smaller processor boxes. Removable rotating media is all but obsolete, reducing the need to access the processor box. Less paperwork is needed on the desktop, with instructional material being provided via the computer and student work being typed directly into it.

A computer lab designed for teaching might currently have desks 1,200 x 900 mm, as specified in Australian Standard 3590.2-1990 single task office desks used for for screen based workstations. It is proposed to reduce the single row desks to 900 x 750 mm, with a 150 mm deep curve cut out of the front, in which the student sits. The face to face double row island desks would be 1050 mm deep, with a row of monitors down the middle of the shared area of the desk, giving each student the same space as for the single desks.

Computer Case and Monitor Size Reduction

The original IBM PC case was (HxWxD) 140 x 495 x 408 mm (XT type 5150 of 1984) taking up a large proportion of a desktop. A typical slimline desktop case is now 112 x 398 x 362 (Dell OptiPlex 330 Desktop). These are small enough to be mounted under a desktop. Manufacturers are now introducing desktop computers with the footprint slightly larger than a DVD Drive: 165 x 165 mm (Apple Mac mini). These are small enough to be placed on the desktop next to the monitor.

A typical CRT monitor is 419mm deep (Dell E773c 17-inch CRT Monitor). The depth of a typical LCD monitor is 165 mm (Dell E2209W 22" LCD monitor is 163.9 mm), saving 254 mm of desk depth.

Older PS/2 style computer keyboards are about 450 mm wide (Lenovo 31P7415 is 453 mm). Newer compact keyboards, are slightly narrower at about 430 mm (Dell PH316 is 432mm x 152 mm). Some sub-compact keyboards are as small as 400 mm.

Desk Depth

Provided there is room for the student's legs underneath, the depth of the desk can reduced by about 260 mm when a CRT screen is replaced with an LCD, without reducing the usable desk space. With the LCD stand taking up 165 mm at the back of a 600 mm deep desk, this would leave 435 mm, which is sufficient space for a computer keyboard and A4 paperwork. With the keyboard pushed under the monitor, there would be room for a textbook and A4 paper.

Desk Width

With 200mm to operate a mouse (Fellowes - Mouse pad 200 mm), a compact keyboard would leave room for an A4 notebook (210 mm) and 20 mm between each item on a 900 mm wide desk.

Fitting Desks in the Room

A row of five 1200 mm desks is 6m wide. Reducing to 900 mm desks allows seven desks in a row, with the loss of 300 mm circulation space at the front of the room. This would increase the room capacity from 20 to 28.

If the single row desks are reduced from 900 mm to 600 mm deep, the double row desks made correspondingly narrower, and the space between them from 1300 mm to 1220 mm (the US minimum for wheelchair access), an extra two rows of desks could be added, increasing the room from four to six rows. With 1200 mm width desks, this increases the capacity to 6 rows of 5 students = 30 students. With narrower 900 mm desks, this increases the capacity to 6 rows of 7 students = 42 students.

Heat output

Apart from the space requirements, air conditioning loads need also to be considered from fitting twice as many students into a room. However, the drop in energy use of modern computers will just about compensate for the heat produced by twice as many people.

The Dell E773c CRT consumes 71 Watt, whereas the Dell E178FP 17-inch LCD is only 40 Watt. The Dell OptiPlex 330 Desktop PC has a 280W power supply. The Apple Mac mini has a 110 W power supply. A person puts out about 60 Watt of heat at rest.

So an old system would produce 340 Watt of heat per workstation and the new one and a new one 210 Watt. This is not quite half, but I expect that the figures the air conditioning engineers use are based on higher power levels.

Making the room look larger

Leaving other aspects of the room design unchanged but adding twice as many students could result in a crowded looking space. Changes can be made to increase the effective space and also make it appear larger:

Curved desks occupied at the Learning Commons of the Unviersity of Calgary Library* Curved desk fronts: Having a curved front edge, projecting out 150 mm each side of the student would make the desks larger, without greatly reducing circulation space in the room. This would also better define each student's desk area. The inward curve where the student sat would accommodate an empty chair, providing additional space when the room is not fully occupied and giving it a less cluttered look. This is similar to the arrangement for casual use terminals at the Information Commons, University of Calgary.

Serpentine trading desks at Connecticut School of Business
* Staggered Seating: In typical computer labs, students sit in rows, one behind the other, or facing each other across a shared desk. If the seating is instead staggered, so that students do not face each other, and the backs of their chairs do not back onto another, there is more effective space and the room will look less cramped. The depth of the double row desks could be reduced in this way. This is the arrangement used for the Connecticut School of Business.

Curvilinear  desks unoccupied at the Learning Commons of the Unviersity of Calgary Library* Angled Seating: Typical computer labs have the students facing either the front or side walls. If the students instead face slightly to the front of the room, at about 75 degrees, this will increase the effective depth of the desks. This will also make it easier to see a presentation at the front of the room and their own screen at the same time for blended learning. In may computer classrooms it can be difficult to see the front of the room past all the rows of computer screens. This arrangement is used in the computer classrooms at the Information Commons, University of Calgary.

* Concealed Cabling: Computer cabling and power supply "bricks" commonly clutter the work surface in computer labs. Where cabling is buried in desks or walls, maintenance can be difficult. Instead the cabling can be run in a tray under the rear of the desks, and brought up through a hole in the desktop. This allows the cabling to be hidden, but accessible for maintenance. Standard, low cost power and data cables can be used with excess cable stored in the trays. The University of Queensland Ezones uses this arrangement with wire baskets under the desks to hold the cabling.

* Computers Under Desks or Smaller computers:
The largest item cluttering the desks, but the most difficult to remove, is the PC box. Previously this needed to be accessible to the student for inserting floppy disks or CD/DVD drives. But these are no longer required and the processor box can be placed under the desk, or a smaller unit fitted to the LCD stand. Extension cables can be used to make audio and USB sockets accessible on the desktop. Power sockets can be provided in the desktop, if needed for ancillary equipment, and a power switch to turn off all equipment. PCs can be mounted on the under surface of the desk, between each student, with straps, allowing them to be accessible but out of sight. Straps are used to retain computers on the USS Blue Ridge.

* Instructor Console on end of Student Desks: Teaching spaces typically have a rectangular console at the front for audiovisual equipment, controls and a work surface. This takes up space and looks cluttered. Instead, the front of one of the student desks can be extended for the instructor console. This can have a rectangular box underneath for audio visual equipment, with the top curved to match the other desktops and raised for presentation. It is used for the University of Queensland Ezones.

* Color: Labs are usually a dull mix of muted colours. The usual beige or grey plastic strip placed around the edges of desks can be replaced with one keyed to one of the building colours. This will define the space much more clearly and make it look larger, as well as more interesting.

* Computer Cut Desks: To keep costs down, and raise green credentials, it may be possible to recycle the existing desks and legs, cut to the news size. Small numbers of desks can be cut from low cost manufactured board, laminate or corrugated core sandwich from recycled wood pulp. Larger quantities can be computer cut. Modular systems as featured in "Conference and Communication Environments: Conference. Excellence" are likely to be prohibitively expensive. While movable modular desks may seem a good idea, as Dr Kathy Lynch at the University of the Sunshine Coast pointed out, they may be rarely moved in practice. Where desktop computers are installed it is very unlikely that a system which allows them to be secure and movable is feasable.

* Interactive Screens: An interactive whiteboard could be considered as part of the fit-out, as was pointed out to me at Hawker Primary School. The interactive whiteboard takes no additional space. Side walls can have have supplementary projection or LCD displays (with low power LED back lights), repeating the main image for students who can't easily see the front of the room.

ps: The curve on the desks could be a "hyperbola": an appropriate shape for the "hyperbole" commonly expressed in teaching rooms. ;-)

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Blogger Claudia said...

We are in the process of building a new STEM computer lab for an elementary school in the USA. I really liked this post, particularly on how to save space with curved desks. Do you know who manufactures them? I'll contact the University of Calgary, but wondered if you know. Thanks. Claudia

July 21, 2009 11:07 PM  

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