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5.13 A drawing office programme allocates individual team members' appropriate work loads. The elemental approach means that DC, for example, can follow the (3-) element right through, dealing with it in its location, component and assembly aspects

5.13 A drawing office programme allocates individual team members' appropriate work loads. The elemental approach means that DC, for example, can follow the (3-) element right through, dealing with it in its location, component and assembly aspects

The sequence to take

But take one step at a time. There are several degrees of rationalisation and they should be introduced in sequence:

• Standardise drawing size and format for all new projects entering production drawing stage.

• Rationalise new projects into the schedule, location, assembly, component format.

• Select one such project for the experimental application of CI/SfB coding and let it run through its production phase before attempting a general application of the method. You will thus have built up some office case-law to assist in answering the query 'How do we code for this situation?' which will arise on subsequent projects.

• Now that you have each project producing component and assembly information in a common format and within the context of a coding system offering ease of retrieval, you are in a position, if you so wish, to introduce standard solutions to various aspects of your detailing.

What does it cost?

As to the cost of introducing (and indeed of operating) new drawing methods one is on less certain ground.

Certainly all the available feedback suggests that it is unusual for a practice to revert to unstructured working drawings once it has started producing structured sets, which seems to indicate that at least the structured set is not so overwhelmingly expensive to produce as to render it uneconomic in practice. Short of carrying out parallel drawing exercises using two methods and comparing the cost there is no real way of being sure.

The initial economics of switching to CAD are even less easy to identify. Apart from the cost of the equipment, the cost of training staff to use it must be considered, particularly among those of a generation less used to computer technology than their younger colleagues. (Hesitant principals may take courage from consideration of just how long they themselves took to learn to draw competently with pen and set square.)

What is clear, however, is that the more comprehensive nature of the information likely to be produced within a structured format, its greater potential for co-ordination and the greater ease of information retrieval which it offers to the contractor, will all combine to reduce time-consuming queries once the work is on site. An honest analysis of office time spent on so-called 'site operations' is perhaps a salutary exercise for any practice. Bearing in mind that the plan of work defines this stage as consisting of 'Following plans through to practical completion of the building', consider how much time in practice is spent in the drawing office in amending existing drawings and in providing new ones to illustrate details which could (and in retrospect clearly should) have been provided during the working drawings stage. Consider also the predictable reaction of the poor unfortunate who is dragged back a year later from the multi-million pounds Arabian Nights fantasy on which he is happily engaged in order to sort out the door detail he had unfortunately omitted from the working drawing set which had been his previous task. (In Parkinsonian terms it may be stated that if x is the time spent in hoping the problem will just go away, y is the time spent in reconciling oneself to the fact that it isn't going to, z is the time spent in seeking out the necessary reference documents, and t is the amount of drawing time the detail should reasonably take, then the sum of x + y + z will be inversely proportional to t. But never less than a week.) It must always be cheaper to produce information at the right time. On the other hand, any change in working method must have some cost implication, as the change to metric dimensioning demonstrated. As with metrication, this cost should be looked upon as an investment for the future.

What may be said with certainty is that within a short space of time all drawings will be produced by CAD, and that examples of working drawings prepared by manual techniques will have taken their place in the RIBA Library alongside those 18th Century drawings on opaque paper from which copies could only be taken by pricking through the salient points on to a further opaque sheet.

The more important consideration is: how will CAD itself develop?

It would seem that computer hardware has evolved to a point where only increased memory capacity and speed of operation remain to be improved. The software is a different matter, and improvements here are likely to be generated by the needs of the drawing office and the site office. Three-dimensional representation is already a reality, and is being used to avoid the clashing of building elements and to convey pictorial information. Can the technique be developed to convey constructional information about the complete building? Is there a demand for such a facility? Who should take the lead? Does the future lie with the development of interactive systems whereby changes in the drawing are reflected instantly in the Quantity Surveyor's cost plan?

The years leading up to the 21st Century look like being exciting ones.

And the future?

A whole new world of technology lies ahead of us. But it is difficult to visualise a bricklayer laying bricks other than by using a drawing to instruct him where to lay them. The roles of the architect and of the architectural drawing office appear to be secure for the foreseeable future.

Appendix 1 Building elements and external features

The degree of detail used in representing any element is dependent on the scale at which it is shown. The examples given below give an indication of what may be considered appropriate for various scales.

Windows

Scale 1:200

Scale 1:100

Scale 1:50 and over

Manholes mmm/z/A

Scale 1:100 and under

Doors

Scale 1:200

Scale 1:100

Scale 1:50 and over

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