And Computers

Once the construction drawings are complete, the designer must decide how to distribute them to the various parties involved in a project. This might be done by making multiple copies through a reproduction process or by sending them electronically through a computer system, such as the Internet.

Along with reproduction processes, the use of computers in design schools and professional offices will be addressed in this chapter. The focus will be on CAD, which is an acronym for computer-aided design or computer-aided drafting. Design involves creating, sketching, drawing, and rendering two-dimensional and three-dimensional spaces and objects. Traditionally, drawings were all done by hand, but now we see the computer taking over many of the repetitive and labor-intensive parts of the process. But even more exciting is that designers can use CAD to do much of their exploration, creation, and presentation. Most designers now see CAD as a tool, similar to the pencil or pen, but much more powerful and dynamic.

This chapter will not attempt to describe the most popular model of computer and its peripherals (hardware) and programs (software), as there is a large variety on the market today, and the technology changes rapidly. Also, preferences for particular software programs differ widely among professional firms, depending on their needs. The reader is encouraged to research the many computers and programs that are available to find those suited to their specific needs.

Figure 16-1 A xerographic machine performs a number of operations for copying drawings and other materials, such as multiple copies, different sizes of paper, reduction, enlargement, and collating.

Reproduction of Drawings

Multiple copies are often made of drawings and used for presentations and as check prints for construction drawings. Copies are also used for competitive bidding and generally distributed to parties such as owners, contractors, subcontractors, and material suppliers during the construction of the project.


For over a hundred years, the prime method of copying drawings was the blueprint process. Originally, the photographic copy process produced a blue background (the white space on the original) with lettering and lines converted to white. From this process, the name blueprint was derived, and can still be heard today when dealing with copies of original drawings. However, the historic method of white print on blue ink is no longer used.

Whiteprint Reproduction

After the blueprint process came the development of the whiteprint, produced through a diazo process. For a whiteprint, the original copy, which must be on translucent vellum or plastic film, is fed through a machine and the image is transferred to a piece of yellow diazo paper. The machine uses ultraviolet light that is directed through the original, bleaching out the diazo dye, except where the pencil or pen lines are. The sheet is then fed through a developer system that fixes the lines permanently in blue, black, or brown — depending on the type of diazo paper used. The blue-line prints are still generally referred to as "blueprints." As with the historic blueprint process, most offices and print shops are phasing out this method of copying in favor of advanced technology.

Electrostatic Reproduction

Today, the xerographic process is the preferred method of making reproductions of drawings. It is fast, very accurate in reproduction quality, and becoming more economical each year. This system produces multiple copies in black lines on white paper (Figure 16-1). Variations can include colored lines on a variety of colored papers or on bond, vellum, plastic, and other surfaces. These copiers can handle a number of paper sizes, multiple copies, collating, and even reducing and enlarging images. One advantage of these machines is that the original does not have to be made on translucent vellum or plastic film, as with the whiteprint process.

Facsimile Copies

A facsimile machine (fax) can be used to copy and transmit drawings over a telephone line to a receiver that reproduces the original drawing (Figure 16-2). The process is fairly fast and convenient, but in most cases, the size is limited to the size of the original that can be placed in the machine. Also, most fax copies on the receiving end do not match the exact size and visual quality of the original. However, the speed of the process makes it a handy tool in the design office.

Digital Printers, Plotters, and Copiers

Although the diazo process is being phased out, it is still an economic method of reproduction and used by some firms for making "blueprint" copies from transparent originals. However, this process is fairly labor-intensive. For example, to reproduce 40 sets of 80 original drawings, an operator must feed each of the 80 originals through the machine one at a time and wait for the 40 copies of each sheet. With the advent of large-format plotters and plain-

paper copiers (Figure 16-3), multiple copies can be made that are less labor-intensive. As the costs of using xerographic copiers comes down, the diazo process will fall into history, as did the blueprint process.

Today, high-speed digital printers are making copying even more economical and improving the quality of the images. Even the photographic process used in the photocopier machines is being replaced with digital and laser technology. Digital technology and Internet usage has also reduced the time required to deliver the designer's originals to the printing company for reproductions, and then to get the originals back again. Now CAD plans can be electronically transferred in a print-ready format to a remote print station or separate print company, while the original file is retained in the design office.

When printing out a drawing from a CAD file, the designer has several basic ways to create the image. The most basic is the use of a small-scale ink-jet plotter that can do multiple copies at BV2 x 11 inch (216 x 279 mm) formats, either in black-and-white or color. Fairly economical machines can also increase these sizes up to 11 x 17 inch (279 x 432 mm) formats (Figure 16-4). For large-scale drawings, the large-scale plotter can reproduce the large sheet sizes commonly used in architectural and engineering offices. This plotter can also print in black-and-white or color (Figure 16-5). However, large-scale machines are generally slower and more costly than the small ink-jet units. Also, rather than making multiple copies on one of these devices, a print is made on a vellum sheet and then physically sent to a print company for the making of multiple copies. Now we are seeing more plot files e-mailed, rather than hand-carried, to the printer.

Figure 16-2 A facsimile machine can be used to copy and transmit drawings over a telephone line.

Figure 16-3 Large-format multifunctional copiers can scan, copy, and print multiple copies by a technique that is less labor-intensive than the diazo process.

Figure 16-4 Small-scale ink-jet printers can do multiple copies in formats up to 11 x 17 inches, in black-and-white or color.

Figure 16-5 For large-format printing, this Hewlett Packard DesignJet plotter can produce D-size black-and-white or color plots in less than four minutes.

Figure 16-5 For large-format printing, this Hewlett Packard DesignJet plotter can produce D-size black-and-white or color plots in less than four minutes.

The other method of printing small drawings is by laser printer, which can accommodate the same sizes as the ink-jet system. Generally, laser printers can create more precise images and are often faster than the ink-jet printers.

Using Computers for Design, Communication, and Drafting

The use of computers has exploded in both design schools and the professional office. Computers are fast and very accurate, which has increased their use for complicated procedures. Hardware and software were originally used primarily for data processing and mathematical calculations. The next step was the use of the computer for drafting and producing construction drawings, and only occasionally for design process drawing. Today, with ever-evolving software and the reduction in size and cost of computers, many designers and students use computer-aided design (CAD) systems throughout the design process. The computer is used to create preliminary designs, photorealistic renderings, and construction draw-ins. Besides CAD, a wide variety of programs are available for estimating, tracking time on projects, word-processing, creating data spreadsheets, exchanging e-mail, and many other uses. Some of the programs are effective for increasing productivity, whereas others — such as games and other accessories — offer a refreshing break from our everyday work schedule.

Many designers still find it quicker to create a rough drawing by hand than with a CAD system. They prefer to use CAD for more complex drawings, particularly ones that involve repetitive operations or similar shapes. CAD can also be more effective and faster than manual drafting for making changes to drawings. Editing functions allow the designer to change only part of the file or draw-

ing, or enlarge/reduce something very quickly. In addition to its use for repetitive tasks and other time-saving needs, the computer is also very effective as a design and presentation tool for creating and drawing three-dimensional objects and spaces. Larger memories and processor speeds have enabled designers to create very realistic and accurate images, which can also be explored in movement or in what is termed virtual reality. For example, buildings and their interiors can be created on screen in real-time three-dimensional space, allowing the observer to "walk" through them. Some programs are interactive, allowing the transformation of objects and spaces in accordance with the viewer's directives.

CAD programs allow the designer to assign lines and objects their own unique layer. Each layer can then be assigned its own individual line weight, or thickness. Line weights in the computer are referred to as pen weights. In this layering system, line work can be easily controlled. The designer can "turn off" layers that are not needed in a particular drawing. These types of programs allow base drawings to serve as "reference" drawings for all others to build off. For example, in AutoCAD® programs, the floor plan can serve as the base drawing for the electrical plan and the furniture-installation plan. When a change is made to the floor plan, it will automatically update the configuration in the electrical and furniture-installation plans, by using the x-referencing command.

CAD drawings and programs also allow a designer to share files with others, such as clients, vendors, colleagues, and consultants. These files can be stored on disks and given to other parties for viewing, printing, and even modifying. Today, however, we see more of this sharing done electronically, by e-mail, or through filetransfer protocol (FTP).

CAD programs are becoming increasingly interconnected, so that one can change a three-dimensional drawing and automatically cause a related change in the two-dimensional drawing stored in the program. This dynamic linking can also produce automatic changes in the 3-D drawing as the designer changes the 2-D drawing.

Although we speak of the interconnectivity of programs, today's computer hardware is also becoming more "unconnected," or wireless. Until recently, the networking of computers and other devices has been accomplished primarily through the use of cables, wiring, and optical lines. Now more and more devices are being "unplugged" by the use of wireless technology — using transmitting and receiving technology to connect multiple devices. We will soon be less hindered by the hardwiring of our individual components, with the freedom to use a basic server that can wirelessly present through a portable video screen or input to a laptop — unfettered with wiring connections. However, security is a concern with these new wireless connections, as direct-wired networks are more secure. New programs are being developed to overcome these obstacles.

Again, it is not the intent of this chapter to present or review all the hundreds of software and hardware selections available today. New developments in computers and programs are made every six months or less, complicating the timing of writing on items that may have changed drastically since the date of this writing. In some cases, new software is introduced and other software is discontinued. The computer will no doubt continue to improve our work habits and needs, affecting how we design and communicate to others. But behind these wonderful machines is still the need for input and direction from a human designer.

Introductory Information

00001 Project Title Page

00005 Certifications Page

00007 Seals Page

00010 Table of Contents

00015 List of Drawings

00020 List of Schedules

Bidding Requirements

00100 Bid Solicitation

00200 Instructions to Bidders

00300 Information Available to Bidders

00400 Bid Forms and Supplements

00490 Bidding Addenda

Contracting Requirements

00500 Agreement

00600 Bonds and Certificates

00700 General Conditions

00800 Supplementary Conditions

00900 Addenda and Modifications

Facilities and Spaces

Facilities and Spaces

Was this article helpful?

0 0
Greener Homes for You

Greener Homes for You

Get All The Support And Guidance You Need To Be A Success At Living Green. This Book Is One Of The Most Valuable Resources In The World When It Comes To Great Tips on Buying, Designing and Building an Eco-friendly Home.

Get My Free Ebook

Post a comment